**HYSPEC: A Crystal-Time-of-Flight [Hy]{.underline}brid
[Spec]{.underline}trometer for the Spallation Neutron Source**

![](media/image1.jpeg){width="5.9319444444444445in"
height="5.571527777777778in"}

[Principal Investigators:]{.underline}

S. M. Shapiro Center for Neutron Science

I. A. Zaliznyak Neutron Scattering Group

> Brookhaven National Laboratory

**EXECUTIVE SUMMARY:**

The study of phase transitions and novel ordered phases in complex
systems remains at the forefront of condensed-matter research. In
studies of superconductivity, magnetism, ferroelectricity, colossal
magnetoresistance, charge order, etc., one is interested in determining
how each type of order occurs, including how and why it arises from the
disordered state. The energy scale for excitations that have an impact
on ordering is typically on the order of a few to tens of meV; this is
the same energy scale for excitations that impact transport properties.
The intensities and energy resolutions obtainable with thermal neutrons
are ideal for such inelastic studies. At the same time, one needs to be
able to detect and monitor the relevant order parameter through elastic
diffraction measurements, which frequently involves measurements of
superlattice peaks that may be extremely weak. Often one wishes to study
correlations that have not achieved long-range order, in which case one
must measure diffuse scattering and be able to discriminate elastic from
inelastic contributions. In many cases understanding the order of
interest requires studying how it is modified or induced by an extreme
environment, such as a strong magnetic field, very low temperature, or
high pressure; this is best accomplished by decoupling the sample
environment from the detector system. In order to exploit the full power
of neutron scattering to distinguish magnetic from nuclear scattering,
it is necessary to implement polarization analysis, with polarization
sensitivity in both the incident and scattered beams. Finally, in order
to discover new phenomena, and to not simply characterize phenomena that
have been discovered at other facilities, one has to be able to work
with small crystals, thus requiring that a spectrometer focus as much
flux as possible into a small spot size.

Up to now, the combination of requirements described above has been met
only by triple-axis spectrometers at steady-state sources. Here we
present the case that by combining time-of-flight spectroscopy with
Bragg focusing optics and the enhanced flux of the pulsed beam that will
be available at the SNS, one can build an instrument that not only
satisfies our needs, but which will also significantly exceed the
performance of the best triple-axis spectrometers at the best
steady-state sources. The instrument that we propose, HYSPEC, fills a
niche of dramatic importance to exciting areas of condensed-matter
physics, one that is not competitively covered by any of the other SNS
instruments that have been considered to date.

HYSPEC was approved by the SNS Experimental Facilities Advisory
Committee (EFAC) at its October, 2002 meeting. Provisionally it has been
assigned beam line which looks at a coupled, supercritical H~2~
moderator (BL 15). To transport the beam from the moderator to the
sample the instrument will have a straight, 20 to 25 meter long, m=3
supermirror guide that will incorporate T~0~, frame overlap and order
suppressing choppers along its length and, near its downstream end, a
counter rotating chopper pair that will serve to define the neutron
burst width and incident energy. A short distance downstream of the
counter-rotating chopper pair, the monochromatic beam will impinge on
either a pyrolytic graphite or (for polarized beam studies) Heusler
alloy vertical-focusing crystal mounted in a drum shield with adjustable
exit angle. Because vertical focusing by crystals is extremely
efficient, the 4(w) x 15 (h) cm^2^ beam exiting the guide will be
reduced to an area as small as 4(w) x 2(h) cm^2^, thus maximizing the
flux at the sample position. A series of collimators and beam definers
will be placed immediately upstream of the sample and a set of radial
collimators in the detector bank just downstream of the sample. In the
polarization-analysis mode the radial collimator would be replaced by a
set of 19 Fe-Si supermirror benders that would make it possible to
measure simultaneously both spin-flip and non-spin-flip processes.
Detection of the neutrons scattered by the sample will be done by 188
^3^He position-sensitive detectors housed in a moveable detector bank
4.5 m from the sample that will cover a horizontal angular range of 60°
and a vertical range of 15°.

HYSPEC's flux-on-sample was compared to the other planned inelastic
instruments CNCS, ARCS and HRCS (which have overlapping energy ranges
and resolutions) using the MCSTAS Monte Carlo simulation program. For
HYSPEC, the maximum flux on sample at a 3% energy resolution was found
to be 1.1 x 10^7^ n/cm^2^/sec at 15 meV. This is a factor of two more
than the maximum flux of CNCS, which is at an energy of 5 meV, and about
ten times more than maximum flux of HRCS and ARCS, which occurs at an
energy around 100 meV. This high sample flux combined with TOF analysis
and the wide angular acceptance of the detector array means that a given
scattered neutron spectrum will be collected in an order of magnitude
less time than on existing single crystal sample instruments.

The easy adaptability of HYSPEC to polarization analysis is unique among
the suite of SNS inelastic instruments. To produce a focused, polarized
beam the PG crystal is simply replaced by a vertical focusing Heusler
alloy crystal. Analysis of the polarization of the scattered neutrons
will be done with a set of 19 broad-spectrum Fe-Si supermirror benders
downstream of the sample: a well-established and extremely reliable
technology. Because the sample-to-detector distance is large, the
spin-flip and non-spin-flip parts of the scattering will fall on
different groups of detectors. This will allow both to be measured
simultaneously.

HYSPEC Instrument Development Team includes an international group of
prominent scientists interested in single crystal inelastic neutron
scattering. They provide input to the design of the spectrometer, high
international visibility of the project, and will assure a high level of
scientific productivity in the future. We are encouraged by the recent
discussion with the French IDT member who has indicated that the Atomic
Energy Commission (CEA) may participate in the HYSPEC project.

Finally, it should be noted that an SNS Inelastic Neutron Scattering
Workshop held on 11/1/99 at ANL recommended that a spectrometer with
almost identical characteristics to HYSPEC be viewed as a "potential
"day-one" instrument" (Appendix B).

**HYSPEC: A Crystal-Time-of-Flight [Hy]{.underline}brid
[Spec]{.underline}trometer**

**for the Spallation Neutron Source**

# Contents

1.  Introduction

2.  Scientific Motivation: Meeting the New Challenges

    1.  Functional Materials and Nanosystems

        1.  Spin Dynamics in Nanostructures (J. J. Rhyne)

        2.  Nanoscale Features of Functional Materials (V. Kiryukhin)

        3.  Anomalous Phonon Behavior (S. Shapiro, G. Shirane)

        4.  Complex Phases in the Intermetallic Alloys (C. Stassis)

    2.  Correlated Phases in Many-Electron Systems (I. Zaliznyak, J.
        Tranquada)

    3.  Strongly Correlated Electrons

        1.  New Challenges for Neutron Scattering (G. H. Lander, S.
            Nagler)

        2.  High-Tc Superconductors and Advanced Polarization Analysis
            on TAS and TOF spectrometers (L.-P. Regnault)

        3.  New Transition Metal Oxides (M. Greven).

    4.  Quantum Critical Points (R. Osborn)

    5.  Geometrically Frustrated Magnets (J. Gardner)

    6.  Quantum Spin Systems (A. Zheludev)

3.  The HYSPEC Spectrometer

    1.  Primary Spectrometer (Monochromator)

    2.  Sample Stage

    3.  Secondary Spectrometer (Analyzer/Detector)

    4.  Polarization Analysis

        1.  The Polarizing Crystal

        2.  The polarization Analyzers

    5.  Performance

        1.  Moderator Choice

    6.  Additional Advantages of the HYSPEC concept

    7.  Future Considerations

4.  Instrument Development Team

    1.  Membership and Composition

    2.  Organization and mission

5.  Project Management Plan

6.  Estimated Budget and Time Scale

Appendix A. CV of the HYSPEC IDT members

Appendix B. SNS Document: IS-1.1.8.2-8004-MM-A-00 (selected pages)

Appendix C. HYSPEC Top Level Specifications (draft)

Appendix D. HYSPEC Estimated Budget and Funding Profile

# INTRODUCTION

This document lays out a proposal by the Instrument Development Team
(IDT) composed of scientists from leading Universities and National
Laboratories to design and build a conceptually new high-flux inelastic
neutron spectrometer at the pulsed Spallation Neutron Source (SNS) at
Oak Ridge. This instrument is intended to supply users of the SNS and
scientific community, of which the IDT is an integral part, with a
platform for ground-breaking investigations of the low-energy
atomic-scale dynamical properties of crystalline solids. It is also
planned that the proposed instrument will be equipped with a
polarization analysis capability, therefore becoming the first polarized
beam inelastic spectrometer in the SNS instrument suite, and the first
successful polarized beam inelastic instrument at a pulsed spallation
source world wide.

The proposed instrument is designed primarily for inelastic and elastic
neutron spectroscopy of single crystals. In fact, the most informative
neutron scattering studies of the dynamical properties of solids nearly
always require single crystal samples, and they are almost invariably
flux-limited. In addition, in measurements with polarization analysis
the available flux is reduced through selection of the particular
neutron polarization, which puts even more stringent limits on the
feasibility of a particular experiment. To date, these investigations
have mostly been carried out on crystal spectrometers at high-flux
reactors, which usually employ focusing Bragg optics to concentrate the
neutron beam on a typically small sample. Construction at Oak Ridge of
the high-luminosity spallation neutron source, which will provide
intense pulsed neutron beams with time-averaged fluxes equal to those at
medium-flux reactors, opens entirely new opportunities for single
crystal neutron spectroscopy. Drawing upon experience acquired during
decades of studies with both crystal and time-of-flight (TOF)
spectrometers, the IDT has developed a conceptual design for a
focused-beam, hybrid time-of-flight instrument with a crystal
monochromator for the SNS called HYSPEC (an acronym for
[hy]{.underline}brid [spec]{.underline}trometer). The proposed
instrument has a potential to collect data more than an order of
magnitude faster than existing steady-source spectrometers over a wide
range of energy transfer (*ħω*) and momentum transfer (***Q***) space,
and will transform the way that data in elastic and inelastic
single-crystal spectroscopy are collected. HYSPEC is optimized to
provide the highest neutron flux on sample in the thermal and epithermal
neutron energy ranges at a good-to-moderate energy resolution. By
providing a flux on sample several times higher than other inelastic
instruments currently planned for the SNS, the proposed instrument will
indeed allow unique ground-breaking measurements, and will ultimately
make polarized beam studies at a pulsed spallation source a realistic
possibility.

Even though the polarized beam option was not considered at the time, a
spectrometer with performance characteristics similar to those of HYSPEC
was identified as one of the potential "day-one" inelastic instruments
for the SNS at the Inelastic Neutron Scattering Workshop[^1] organized
by the SNS at Argonne in 1999. It was included as such in the Workshop
recommendations, along with six other instruments, four of which are
currently approved, with three of those having already been funded and
now under construction. This proposal is a request by the IDT for
funding for the engineering and construction of the HYSPEC spectrometer
on a beamline served by a coupled, 20 K supercritical hydrogen. The
proposal is organized as follows. In the next section we outline the
general scientific motivation for the proposed instrument by presenting
some of the research programs proposed for HYSPEC by the IDT members.
Section 3 contains an overview of the instrument conceptual design, a
discussion of the principles of polarized beam operation, a summary of
the instrument performance characteristics and some future
considerations. Section 4 outlines the structure of the HYSPEC
Instrument Development Team, a management plan is discussed in Section
5, and a tentative budget estimate is given in Section 6 (and Appendix
D). CVs of key IDT members are attached in Appendix A. For reference, an
excerpt from the report of the SNS Inelastic Neutron Scattering Workshop
held on 11/1/99 at ANL, SNS Document: IS-1.1.8.2-8004-MM-A-00, is
attached in Appendix B. Finally, Appendix C is a draft of the HYSPEC Top
Level Specifications which contain a detailed list of the instrument
requirements to implement the conceptual design as proposed by the IDT.

# SCIENTIFIC Motivation: Meeting the new Challenges 

Much of our current understanding of atomic-scale structure and the
dynamical properties of solids and liquids was gained by virtue of
neutron scattering studies. Inelastic neutron spectroscopy provided
physicists with an unprecedented, detailed access to phonon dispersions,
magnetic excitation spectra, soft-modes and critical dynamics at phase
transitions, unrivaled by other experimental techniques. Because the
neutron only interacts very weakly with matter, it is essentially a
non-perturbing probe of the matter's inner structure and dynamics, not
sensitive to charges or surface layers. Therefore, unlike techniques
where photons, or charged particles (eg electrons, muons), which
significantly modify the local electronic environment, are used, neutron
spectroscopy allows determination of the intrinsic, un-perturbed
physical properties of materials. By the same virtue, the neutron is a
highly penetrating and non-destructive probe, allowing the investigation
of microscopic properties of bulk materials (and not just their surface
layers), and studies of samples embedded in a complex sample
environment, such as cryostats, magnets, pressure cells, etc. In fact,
the ability to accept a variety of devices creating extreme sample
environments was one of the key factors that determined tremendous
success of the modern reactor-based neutron spectrometers. Finally,
determination of how partial cross-sections depend on the neutron spin
polarization through the use of various beam-polarizing devices gives an
unrivaled opportunity to separate the structural and magnetic phenomena
on the atomic scale. Incorporating and optimizing these unique features
of the neutron scattering technique in the design of a neutron
spectrometer is extremely important.

The discovery of new materials and novel unexpected phenomena along with
the advent of new experimental techniques invariably leads to major
advances in condensed matter science. One example is the discovery of
strongly correlated electron systems, including heavy-fermions to
high-T~c~ superconductors to manganites exhibiting giant
magneto-resistance effects. These materials present new types of
macroscopic behavior with a strong potential for future technological
applications, which require detailed understanding at the microscopic
level. The neutron scattering studies which are indispensable for such
understanding represent a significant experimental challenge. First of
all, new materials are usually only available in small quantities.
Secondly, the scattering intensities associated with the interesting
features in the electronic structure are often intrinsically small.
Finally, because several contributions to the microscopic electronic
Hamiltonian in these systems are of comparable importance for
determining their macroscopic bulk properties, direct discrimination
between the magnetic scattering by electronic spin and
structural/vibrational scattering by the means of polarization analysis
is vital.

The goal of the present IDT is to design and build an instrument which,
using the unique, high-flux, pulsed neutron beam at the SNS, would meet
the challenges posed for neutron spectroscopy by new scientific
discoveries and breakthroughs in the synthesis of the new materials.
There is a large number of problems that are currently at the forefront
of condensed matter physics and demonstrate the need for an instrument
with the unique capabilities of HYSPEC. In this section we present some
examples which illustrate how HYSPEC is expected to significantly extend
the reach of modern experimental condensed matter science.

# Functional Materials

Fundamental understanding of the microscopic processes governing
physical phenomena in complex functional materials is key to
technological progress. HYSPEC is an indispensable experimental tool
that is needed to obtain such understanding.

# Spin Dynamics in Nanostructures (J. J. Rhyne)

The interest in dynamic processes, in particular magnetic excitations,
as the dimensions of a specimen are reduced to the nanoscale is
currently creating intense scientific interest. This interest ranges
from fundamental questions about the form of the exchange interaction
and resulting magnon dispersion (Heisenberg, Ising, or a modification)
to lifetime and linewidth broadening effects. This is an important area
of nanoscale science that will seriously strain the intensity/resolution
capabilities of neutron techniques to provide relevant answers. Many of
the studies will also benefit from polarized beam techniques. The hybrid
spectrometer, HYSPEC, proposed for the SNS plays a pivotal role in the
investigation of inelastic processes in nanostructures.

Present interest in magnetic nanoscale materials is in two primary areas
-- thin films and superlattices and in true magnetic nanocomposites for
which nanoscale magnetic clusters are precipitated in a non-magnetic
(often amorphous) carrier. Also materials can be prepared where isolated
nanosize clusters are formed in the deposition process and can be
compacted with resulting changes in the interparticle interactions. The
determination of spin dynamics in nanomagnetic materials requires both
extremely high beam intensity (partly because of the small sample
quantities readily available) and also frequently polarized beam
analysis to distinguish the magnon branches from other competing
interactions. Spin excitations of mixed ferromagnetic and
antiferromagnetic character may be observed requiring measurement of
both spin-flip and non-spin flip cross sections to properly interpret
the results. A wide range of available energy resolutions, largely
decoupled from the q resolution, as available with HYSPEC will be of
tremendous advantage in studying lifetime effects as critical dimensions
are reduced.

A conventional ferromagnet exhibits collective excitations with
dispersion at long wavelengths (low q) given by E = Dq^2^ + ∆, where ∆
is an energy gap usually associated with a magnetic anisotropy impeding
the excitation of a spin wave. The spin stiffness parameter, D, is
directly related to the exchange constant. This dispersion relation is
modified in a nanoparticle system leading to finite-size quantization
gaps introduced into the spectrum as the particle size is reduced. A
simple "particle in a box" analogy for spin waves places a lower limit
on the wave vector (q = 2π/d) where d is the particle size and
introduces discrete energy levels with finite gaps in the spin-wave
spectrum given approximately by ∆~sw~ = D π^2^/d^2^ . These gaps vanish
in large particles, and the spin wave spectrum exhibits conventional
dispersion E = Dq^2^.

Hendriksen et al.[^2] have calculated the spin-wave spectrum of
Heisenberg spin clusters of varying size for clusters ranging from 9 to
749 spins corresponding to nanoparticles of sizes from approximately 7 Å
to 32Å and included both bcc and fcc lattice arrangements. Their results
yield a dispersive spin-wave energy with finite-size gaps that vary
quadratically with the size of the cluster. For large spin clusters, the
gaps are relatively small (e.g. 30K (3 meV) for the 749-spin cluster)
but grow to 140K for the 9-spin cluster. Accompanying the formation of
the finite-size gaps is a smearing of the wavevector q, resulting from
the abrupt transition from finite spin S inside a cluster to 0 outside,
which is most pronounced for the smallest clusters. One remarkable
result from the calculation is that there is no softening in the spin
wave energies; in fact the highest state in the 683-spin cluster lies
higher than the maximum bulk spin wave energy. The occurrence of the
finite-size gaps also modifies the Bloch T^3/2^ form of the
low-temperature magnetization producing a power law dependence M(T) =
M(0) \[1 - BT^α^\], with α ≈ 2.0 for a 20Å cluster and down to α = 1.5
for an infinite size cluster.

The pioneering studies of excitations in nanoparticles were done by
Hennion et al.[^3] on approximately 20Å Fe in an alumina substrate. They
found a dual dynamical system consisting of a longitudinal mode
corresponding to spin relaxation and a semi-transverse mode reflecting
the spin fluctuations. These modes merged into a single isotropic mode
at high T with a temperature-independent fluctuation time they related
to the spin anisotropy of individual particles. Subsequently, in a
system with larger Fe particles (≈ 50Å)[^4], they observed the evolution
of the fast dynamic magnetization component from a quasi-elastic
lineshape into an inelastic lineshape at low temperatures reflecting
damped spin waves. Antiferromagnetic spin fluctuations in ≈ 150 Å
nanoparticles of hematite were studied by Hansen et al.[^5] who derived
the superparamagnetic spin relaxation time from an analysis of the
quasi-elastic linewidth and also were able to distinguish the energies
of the intraparticle collective excitations.

In the area of spin dynamics in thin films and superlattices the
feasibility of these studies has been demonstrated by Schreyer et
al.[^6] in their study of a superlattice of \[Dy~x~Y~y~\]~m~. This
system has helical spin order and thus the origin of the spin wave
branches is at magnetic-only reflections at incommensurate lattice
positions. The magnetic reflections are divided into two sets of
satellites on either side of corresponding c-axis nuclear reflections.
Thus the total spectral weight is split between branches from each
reflection. In addition to the branches from the multiple incommensurate
satellite positions, the magnetic coherence across bilayers of the
superlattice produces multiple branches from each magnetic satellite
separated in q by 2π/Γ, where Γ is the bilayer thickness. Existing
spectrometers do not have sufficient resolution/intensity trade-off to
allow the separation of these multiple branches, and thus the published
data are an average over the respective superlattice harmonic branches.
A much more intense neutron source combined with a spectrometer such as
HYSPEC is anticipated to provide sufficient intensity at the necessary
resolution to separate the harmonic spin-wave branches.

The significant intensity advantages offered by HYSPEC combined with
full polarization analysis, and highly flexible control over resolution
should make this instrument unequalled for the study of magnetic
excitations in nanoscale magnetic materials.

# Nanoscale Features of Functional Materials (V. Kiryukhin)

The drastically enhanced electronic and magnetic responses occurring in
complex functional materials as a result of inhomogeneity on a
microscopic length scale have recently attracted significant attention.
Both fundamental properties, and enhanced materials characteristics
potentially useful for industrial applications are currently being
actively investigated. During the last 5 years, it has become clear, for
example, that nanoscale inhomogeneities are intrinsic to a number of
important oxide systems, such as superconducting cuprates[^7],
magnetoresistive manganites[^8], and lead-based relaxor
ferroelectrics.[^9] Also, understanding and controlling the giant
structural, optical, and magnetic responses of inhomogeneous materials
holds great potential for the creation of technologically advanced
consumer products.

Some of the most important systems discussed above exhibit nanoscale
magnetic inhomogeneities. In magnetoresistive manganites, for example,
nanoscale magnetic inhomogeneities play the crucial role in the
so-called Colossal Magnetoresistance (CMR) effect.[^10] While it is
known that nanoscale magnetic regions exist in these materials, the
structural and magnetic properties of these regions remain largely
uncharacterized.Error: Reference source not found^,^[^11] To understand
the physics of the CMR effect, and to guide future work for the
synthesis of materials with enhanced magnetoresistive properties, it is
crucial to determine the magnetic and structural properties of the
inhomogeneous states realized in these materials.

Another class of experimental systems that has recently attracted
significant attention are doped magnetic semiconductors, such as
Mn-doped GaAs and InAs, and Co-doped ZnO and TiO~2~.[^12] ^,^[^13] The
recent claimsError: Reference source not found of synthesis of
room-temperature magnetic semiconductors have generated a significant
controversy. It is becoming clear now, that in many cases the prepared
systems are actually very fine mixtures of non-magnetic semiconductors
(e.g., GaAs or InAs) and ferromagnetic metals (e.g., MnAs or MnSb).
Physical properties drastically evolve when the mixed systems vary from
complete solid solution to macroscopically phase-separated materials.
[^14] Some of these systems exhibit very large values of
magnetoresistance.[^15] A number of these materials can now be
synthesised in the bulk form. In order to understand this intriguing
behavior, it is essential to characterize the microscopic properties of
these materials, with special attention paid to the nanoscale magnetism.
In this case, as well as in the CMR manganites discussed above,
characterization of both static and dynamic magnetic properties will be
of great importance. In particular, the dynamic magnetic properties of
the nanoscale regions are expected to be significantly different from
the corresponding bulk systems. In fact, drastic changes in the lattice
dynamics properties have recently been observed in relaxor
ferroelectrics,Error: Reference source not found which can be considered
a non-magnetic analogue to the systems\
described here.

Polarized neutrons will, undoubtedly, be one of the most effective tools
to study the nanoscale magnetism in these, and related, systems. A very
important factor underlying the usefulness of this probe is that
magnetic signals from systems inhomogeneous on nanoscale are both
delocalized in the reciprocal space, and spread in energy, and are,
therefore, weak. In addition, the nonmagnetic background is typically
strongly enhanced in such systems. With the proposed spectrometer
(HYSPEC) it would be possible to successfully separate diffuse magnetic
signals from the background, such as multiple Bragg scattering, phonons,
and incoherent scattering due to isotopic disorder. The polarization
analysis will be of crucial importance.

# Anomalous Phonon Behavior (S. Shapiro, G. Shirane)

It has long been known that structural phase transformations occurring
in materials such as ferroelectrics are driven by a lattice vibrational
mode whose frequency tends to zero at the transformation temperature.
This so-called 'soft' mode usually occurs at a well defined wavevector
in a particular optic or acoustic phonon branch and is frequently
accompanied by a 'central' peak, i.e. divergent elastic scattering. The
anomalies associated with the soft mode result in very anisotropic
dispersion curves. Recent work on ferroelectics like PZT and PMNError:
Reference source not found and on shape memory alloys such as Ni-Al,
Ti-Pd, and Ni~2~MnGa have demonstrated the need for good wave-vector
resolution and for minimization of the extraneous elastic scattering
from the sample environment. It also makes clear that single crystals
are necessary. Most often these crystals are grown explicitly for
neutron scattering experiments and tend to be small. Focussing of the
incident beam is therefore vital to assure the maximum number of
neutrons impinging on the sample; a requirement met by the proposed
HYSPEC instrument. A sample stage accepting broad range of sample
environment devices, combined with the flexibility to define the sample
scattering volume by using the collimators and beam definers, and,
therefore, efficiently suppress the incoherent background, is another
crucial advantage for studying the coherent (*eg* phonon) scattering
from single crystals offered by HYSPEC.

# Complex Phases in the Intermetallic Alloys (C. Stassis)

The proposed HYSPEC spectrometer will be a world-class instrument with
polarization analysis capability, a feature that makes it a unique
instrument among those to be installed at SNS. Actually, the capability
of using polarized neutrons is essential in practically any detailed
study of the magnetic properties of condensed matter systems. Such
studies extend from the determination of the magnetic form factor to a
detailed analysis of magneto-vibrational scattering studies, and provide
invaluable information about the magnetic properties and, most
importantly, the interactions between magnetic and other excitations in
condensed matter systems. Currently though, only for one of the
reflectometers planned for the SNS is a simple polarized neutron
capability envisaged. Polarization analysis capability of the instrument
is of particular importance for the study of complex phases. These
phases exhibit complicated arrangements of various interacting degrees
of freedom (such as spin, orbital moment, charge, etc.), with
fascinating physical properties, some of which may be exploited in
emerging technologies ranging from high-T~c~ superconductivity and spin
valves to photonic switches and quantum computing. The well-known
examples of such systems, presently under intense experimental and
theoretical scrutiny, are the various phases of superconducting cuprates
and the magnetoresistive manganites.

Among the complex systems whose physical properties can be exploited in
emerging technologies and which therefore have recently attracted
considerable attention are the intermetallic compounds of
R~5~(Si~x~Ge~1-x~)~4~ family. This family was discovered over thirty
years ago[^16], and has recently opened up an unprecedented opportunity
to solve the century-old problem of the intrinsic relationships between
the chemical composition, atomic structure and properties of metallic
materials. These compounds exist in nearly every R-Si-Ge system, and the
distribution and room temperature crystallography of the
R~5~(Si~x~Ge~1‑x~)~4~ phases is illustrated in Figure
2.1.![](media/image2.jpeg){width="3.772222222222222in"
height="2.8069444444444445in"}

The crystal structures of the R~5~(Si~x~Ge~1‑x~)~4~ phases consist of 36
atoms per unit cell distributed among 6 to 9 independent
crystallographic sites.[^17] These alloys exhibit a number of diverse
and unique properties[^18] associated with both their naturally layered
crystal structures and the combined magnetic-crystallographic
transformations [at low temperatures]{.underline}, driven by a
reversible breaking and reforming of specific covalent Si(Ge)-Si(Ge)
bonds (Fig. 2.2, left). The crystal structures change via a
martensitic-like collective shear movement of sub-nanometer thick slabs
by as much as 1.1 Å and are easily affected by magnetic field,
temperature, and pressure. The transitions are accompanied by a giant
magnetocaloric effect, a colossal magnetostriction, and a giant
magnetoresistance, suggesting many possible technological applications
in sensors and energy-transforming devices through intelligent
manipulation of the phase transformation by composition, applied fields,
temperature, and pressure.

For the most part, identical crystallographic transition also occurs [at
high temperature]{.underline} in the paramagnetic state (Fig. 2.2,
right) when the alloy stoichiometries are near critical (i.e. those
where compositional variations induce a crystallographic phase change).
X-ray powder diffraction measurements indicate that both the
low-temperature magnetically ordered and the high-temperature
magnetically disordered orthorhombic Gd~5~Si~4~-type phases are the
same. Preliminary first principles calculations[^19] indicate, on the
other hand, that the high temperature phase transition may be an
order-disorder transformation, in which Si and Ge atoms are
redistributed among their respective lattice sites. This
crystallographic phase change has a far-reaching effect on the magnetic
properties of the material, as illustrated in Fig. 2.3.

Only systematic neutron scattering studies as a function of composition,
temperature, magnetic field, and pressure can provide a detailed
understanding of the various phases of these systems, the
magnetic-crystallographic transformations and their origin. For such
detailed studies, the polarization analysis capability of HYSPEC will be
an invaluable tool, since it is essential to establish the origin
(magnetic or nuclear) of a large number of peaks observed in the elastic
and inelastic neutron scattering studies of these materials. Such
detailed studies, combined with first principle calculations, are
essential for a fundamental understanding of the fascinating properties
of these compounds (such as the magnetocaloric effect). The proposed
instrument at the high intensity SNS facility is the ideal tool for such
detailed investigations.

# Correlated Phases in Many-Electron Systems (I. Zaliznyak, J. Tranquada)

The ground states of many-electron systems with spin, orbital and/or
charge/valence degeneracy often exhibit non-trivial arrangements of
these degrees of freedom which lead to many fascinating physical
properties. Recently much attention has been paid to exploring the
charge and/or orbital-ordered phases in transition metal oxides such as
the superconducting cuprates and magnetoresistive manganites.[^20]
Understanding the nature and origin of these phases is of both
fundamental importance and technological interest. Neutron scattering is
the most informative and least perturbing experimental way of providing
information on the correlated structural distortions and/or magnetic
correlations in the charge/orbital/spin-ordered phases. Among the unique
features inherent to the neutron scattering approach is that it provides
both good energy and wavevector resolution, which permits accurate
discrimination between the static and dynamic correlations and allows
separate characterization of the corresponding correlation ranges.
Examples where this is of crucial importance are the recent observations
of stripe liquid phases in the doped layered nickelates,[^21]
incommensurate dynamical correlation in the cuprate superconductors[^22]
and characterization of dynamical slow-down in the course of the
spin-glass freezing transition in the half-doped cobaltate
La~1.5~Sr~0.5~CoO~4~.[^23] Such capabilities would also provide an
excellent opportunity for studying other diverse glassy and
short-range-ordered systems and the glass transformations in both "hard"
and "soft" condensed matter systems.

A spectrometer, optimized for studies of the short- and long-range
static and dynamic correlations in single crystals should be designed to
have both small elastic and a negligible inelastic background, a
symmetric and well-reproduced resolution function (permitting a
straightforward and reliable (de)convolution procedure) and have a
polarization analysis capability to distinguish between structural and
magnetic scattering. Equally important, it should provide complete and
continuous coverage of a significant volume in the reciprocal space of
the crystal with both energy and wavevector resolution easily adaptable
to the type of the problem studied. Finally, it is essential that such
an instrument be easily equipped with a variety of sample environments
since definitive insight into the nature of many-electron correlated
phases is often obtained by studying how they are affected by changes in
external magnetic field, temperature, pressure, etc. As it is evident
from Section 3, the proposed HYSPEC spectrometer is designed to both
provide superior performance and to address these concerns.

# Strongly Correlated Electrons 

# New Challenges for Neutron Scattering (G. Lander, S. Nagler)

Strongly correlated electron systems, from heavy-Fermions to high-T~c~
and to compounds exhibiting giant magneto-resistance effects, has added
a new class of materials to those with which we are familiar. Of crucial
significance in these materials are the role of electron correlation
energies and the interaction of the lattice with the spin degrees of
freedom. Unlike the BCS superconductors in which vibrational degrees of
freedom (the phonons) play a key role in mediating superconductivity,
the new phenomena are classified as having a range of interactions, with
the dominant one often difficult to identify.

Neutron inelastic scattering is the single most important probe for
unraveling the energetics and spatial dependencies of these
interactions. At the same time, we have to be able to separate
interactions that are electronic from those that are vibrational. This
requires polarized neutrons, and very often polarization analysis. We
may demonstrate the argument by invoking the pioneering work by Axe and
Shirane[^24] on the vibrational spectra of Nb~3~Sn above and below T~c~.
These experiments, performed in the 1970s, used unpolarized neutrons.
Because superconductivity in BCS materials are dominated by vibrational
energies there has never been any doubt that the measurements were of
phonons. However, if we think today of the superconductivity of
UPd~2~Al~3~ or of high-T~c~ materials, that question is much harder to
answer. In both UPd~2~Al~3~ [^25] and high-T~c~ materials[^26] full
polarization analysis has proved of enormous value in separating the
electronic and lattice effects.

Another challenge to our understanding of the strongly correlated
electron systems is presented by Ruthenates and other 4d and 5d based
Ruddlesden-Popper and pyrochlore structures. The typical energy scales
in these systems are a few meV, and they tend to show odd incommensurate
fluctuations similar to those in high-T~c~ type materials, as well as
quantum critical behavior in the doped materials. It would be very
useful to study the fluctuations in these materials using fully
polarized inelastic scattering.

We need to continue to develop the technology of polarized beams and
polarization analysis (PA), so that these experiments can extend over a
wider range of energy than presently available and not be so demanding
in terms of intensity. Very large crystals are presently required to map
out excitations in full PA ,[^27] which means that the technique cannot
be generally used. An instrument at the SNS will therefore open a
completely new field of endeavor. Not just to be able to perform PA on
selected excitations, but, more importantly, to construct S(***Q**,ω*)
maps of spin-flip and non-spin-flip intensity.

Furthermore, efforts in three-dimensional polarization analysis, now
done almost exclusively with the spherical neutron polarimeter at the
ILL, can often make unambiguous identification of magnetic
configurations[^28] and need to be implemented on a wider scale. Its
extension into inelastic scattering is just beginning.[^29] Many
surprises in our understanding of magnetism, and in defining precise
interactions, will emerge with the use of polarized neutrons.

# High-Tc Superconductors and Advanced Polarization Analysis using TAS and TOF spectrometers (L.-P. Regnault)

Much of the present condensed matter research is devoted to
understanding the physics of \"strongly correlated electronic systems\".
This class of systems encompasses a large variety of physical
situations: un-conventional \"d-wave\" superconductivity in high-T~c~
superconductors (LSCO, YBCO\...) or spin-ladder cuprates
(Sr~14~Cu~42~O~41~...), un-conventional \"p-wave\" superconductivity
(Sr~2~RuO~4~, UGe~2~, CePd~2~Al~2~\...), charge-ordered materials
(NaV~2~O~5~, Sr~14~Cu~24~O~41~, LaNiO~4+y~\...), spin-Peierls materials
(CuGeO~3~, FeOCl, Pb\[Cu(SO~4~)(OH)~2~\]\...), exotic spin dynamics in
quantum-chain systems (J~1~-J~2~ systems, alternating chains,
Haldane-gap chains, dimer systems, magnetization-plateau systems\...),
highly frustrated systems (kagome, J~1~-J~2~-J~3~ honeycomb,
pyrochlore\...), etc.

The physics which is involved in all these systems may be understood
from the competition of different degrees of freedom: spin, orbit,
charge and lattice distortion. The understanding of mechanisms at the
origin of exotic properties is only possible if one can determine
accurately and unequivocally the wave vector and energy dependencies not
only of the \"standard\" correlation functions (i.e. those coupling
identical degrees of freedom : \<spin-spin\>, \<orbit-orbit\>,
\<displacement-displacement\>\...), but also the \"hybrid\" correlations
functions coupling different degrees of freedom (\<spin-orbit\>,
\<spin-displacement\>, \<orbit-displacement\>\...). To our knowledge,
the only way to solve this problem is to measure the magnetic-magnetic
(MM), nuclear-nuclear (NN) and magnetic-nuclear (interference) terms
using the inelastic polarized neutron scattering in conjunction with a
powerful polarization analysis technique.

The best known polarization analysis technique is the so-called
\"longitudinal polarization analysis\" (LPA) method invented a long time
ago by Shull, Moon, Riste and Kohler.[^30] The LPA is invaluable to
obtain separately the magnetic and structural contributions, or the
various magnetic components at a given scattering vector. We have
recently used the LPA on IN22 at ILL to determine directly the magnetic
excitation spectrum in the high-Tc compound YBCO~6.85~ (Fig. 2.4)[^31]
and in ladder material Sr~14~Cu~24~O~41~.[^32] The advantage of using a
polarized beam versus an unpolarized one is clearly demonstrated in Fig.
2.4. The magnetic response is superposed onto a series of more or less
well-controlled structural features (phonons, "braggons",
"spurions"\...), which render the determination highly uncertain. The
same scan performed with a polarized beam allows a very precise
determination of the magnetic contributions (in particular the resonant
peak at 41 meV and the IC dynamic correlations existing between 25 meV
and 41 meV). The \"normal\" method would have consisted in performing
constant-energy scans at different energies to determine both the signal
and the background.

Some years ago (in the early 80\'s), the LPA was successfully used on
IN12 at ILL to demonstrate the relevance of soliton-type non-linear
excitations in the quasi-1D antiferromagnet TMMC.[^33] In particular,
the use of polarization analysis was fundamental to determine
equivocally and separately the contribution S^^(***Q**,ω*), directly
related to the solitons, and S^⊥^(***Q**,ω*), related to the
inter-soliton spins, Fig. 2.5. With un-polarized neutrons, the method to
separate both contributions would have consisted in measuring the
Q-dependence of the response, which is problematic if one contribution
is much smaller than the other. A recent example is measurement of the
SF and NSF contributions in CuGeO~3~, a prototype spin-Peierls system,
which allowed a spectacular determination of all the magnetic (bound
states, continuum...) and phonon modes, and the double-gap structure of
the magnetic excitation spectrum.

The LPA method can be transposed to TOF machine. At least there is no
conceptual interdiction, although the practical realization may not be
simple. As important it has been, the LPA method is still a relatively
\"old\" and \"rustic\" method. Indeed, LPA only recovers one part of the
information. Because the incident polarization direction is selected by
applying a magnetic field on the sample, only a single projection of the
polarization vector after scattering can be determined. In the last
decade an important effort has been made at ILL to develop a new
polarization analysis technique, offering the possibility to measure all
three components of the final neutron polarization (CRYOPAD
concept).[^34] The \"spherical neutron polarimetry\" (SNP) is a new
alternative to LPA. It has demonstrated strong capabilities in
diffraction, in particular to resolve non-trivial magnetic
structures.[^35] By accessing the \"off-diagonal\" components of the
polarization tensor (i.e. P~xy~,P~xz~,P~yz~\...), the method allows, in
principle, to determine the so-called \"inelastic nuclear-magnetic
interference\" (INMI) terms.[^36] SNP is a very elegant but difficult
method to measure very-small magnetic or structural **inelastic**
contributions through their interferences with the strong ones. Although
the method has not yet been demonstrated for INS, the SNP could bring
new information for, e.g., the relevance of orbital correlations,
\"hidden-order\", orbital currents in High-T~c~ cuprates or in
heavy-fermion materials (URu~2~Si~2~, etc). This field of investigation
is new for INS and almost all remains to be done.

HYSPEC offers a unique opportunity to develop new polarization analysis
techniques at a pulsed spallation source. Of course, a
broad-band/broad-angle CRYOPAD adapted to TOF spectrometry has not yet
been built (although there is a project and some ideas at ILL). On the
other hand, the flexibility of HYSPEC associated with its \"hybrid\"
nature, will make the \"mono-detector/narrow beam\" SNP method easily
adaptable.

# New Transition Metal Oxides (M. Greven)

Transition metal oxides are highly complex materials with coupled
charge, spin, and lattice degrees of freedom. These materials are at the
frontier of condensed matter physics since they provide myriad
possibilities to discover and study novel fundamental phenomena and
phases, and because some of their properties, such as high-temperature
superconductivity and colossal magnetoresistance, have potential
applications in technology. The properties of these systems are
generally found to be highly anomalous and have eluded a huge amount of
effort over the last 15 years to describe them within the context of
conventional theories. Thus they present a formidable challenge to
develop new theoretical concepts toward a deeper understanding of the
solid state.

Neutron scattering plays an invaluable role in materials science and
condensed matter physics, as it provides essential structural and
magnetic information about new phases of matter and the transitions
between them. Such experiments often rely on timely access to sizable,
high-quality samples. Over the past few years, we have built a lab at
Stanford University to grow some of the most challenging cuprates and
manganites for scattering experiments. The center pieces of our crystal
growth are three optical floating-zone furnaces which have allowed us,
for the first time, to grow sizable crystals of the quantum percolation
system La~2~(Cu,Zn,Mg)O~4~,[^37] and the single-layer bismuth-based
superconductor (Bi2201). A picture of an optimally doped Bi2201 sample
with T~c~ of 36K is shown in Figure 2.6.

A successful mapping of the antiferromagnetic fluctuations in Bi2201 and
related transition metal oxides will be greatly facilitated by the
superior neutron flux on the available realistic samples, such as shown
in Figure 2.6, and polarized-neutron capabilities of HYSPEC. Quite
generally, while the coupling between electrons and phonons is known to
be the driving mechanism for Cooper-pair formation in conventional
superconductors, its role in the high-Tc superconductors is the subject
of intense research efforts.[^38] It appears likely that both structural
and magnetic degrees of freedom give rise to the fascinating properties
of these and related complex oxides, and polarized-neutron capabilities
of HYSPEC will help greatly in separating out the two contributions in
the relevant energy range.

# Quantum Critical Points (R. Osborn)

A quantum critical point is a phase transition in which the temperature
at which long-range order is established is suppressed to zero by
quantum disorder. This may be induced either externally, e.g. with the
application of pressure or magnetic field, or internally through either
compositional variations or by increasing disorder. Close to a quantum
critical point, the energy scale of critical fluctuations is determined
by the temperature which leads to highly unusual scaling of the critical
dynamics. Universal scaling in *ω*/T has been observed by inelastic
neutron scattering in at least two systems believed to be close to
quantum critical points, UCu~5-x~Pd~x~ and CeCu~6-x~Au~x~. Such
experiments are challenging because they require measurements over a
wide range of energies. Thus far, the most complete data have been
obtained on time-of-flight spectrometers at both reactor and pulsed
neutron sources. However, the need for large samples has necessitated
the use of systems in which quantum criticality is induced by sample
non-stoichiometry rather than by an extreme sample environment.
Theoretically, it is important to reproduce this scaling behavior in
high-quality single crystals that are stoichiometric so that atomic
disorder can be discounted as a contributory factor. For instance, the
most reliable examples of quantum phase transitions are in systems such
as CePd~2~Si~2~ and ZrZn~2~, occuring at pressures of 28 kbar and 21
kbar respectively. There is also evidence that metamagnetic transitions
in some heavy fermion compounds - commonly occurring in fields of
greater than 10 T - may be associated with quantum phase transitions. An
instrument with the ability to utilize versatile extreme sample
environments, such as HYSPEC, will be especially valuable in
investigating quantum phase transitions. Also, the focusing properties
of HYSPEC will be vitally important in view of limited sample sizes and
volumes.

# Geometrically Frustrated Magnets (J. Gardner)

The study of geometrically frustrated magnetic materials[^39] has over
the past decade resulted in several influential pieces of work[^40] in
the general area of model magnetism. In these systems, the constraints
put on the system by both the local structure and the magnetic
interactions generally preclude the occurrence of a long range ordered
magnetic state. The phenomenon known as geometric frustration is often
displayed in materials containing antiferromagnetically coupled magnetic
moments which reside on geometrical units, such as triangles and
tetrahedra. The best known example occurs for the two dimensional
triangular framework of unidirectional, classical,
antiferromagnetically-coupled magnetic moments. In such a system, any
two moments can align in a spin-up, spin-down arrangement but the third
cannot satisfy both its nearest neighbours simultaneously. In three
dimensions systems of corner-sharing tetrahedra, the situation is
similar with at least two antiferromagnetic "bonds" frustrated at any
one time. The only constraint on the ground state of such a system, is
the vector sum of the spins on a frustrated unit (the triangle or
tetrahedron) is zero.

In the search for the elusive spin liquid, chemists have synthesized
some exotic, magnetically frustrated spin systems. In particular, many
new spin ½ systems have been prepared in the hunt for the Resonant
Valence Bond state predicted by Anderson.[^41] One possible candidate
was Sr~2~CaReO~6~,[^42] where the spin ½ Re ions are strongly coupled
antiferromagnetically in the face centred cubic lattice. Another
antiferromagnetically-coupled system of great interest lately is
Tb~2~Ti~2~O~7~. This co‑operative paramagnet does not order magnetically
above 17 mK; that is the 5 μ[~B~]{.smallcaps}, Tb^3+^ moments continue
to fluctuate even at this extremely low temperature. Recently however,
we have shown that this system can be driven into a long range ordered
state at \~2 K with the application of exceptionally high pressures (9
GPa). [^43]

For over 5 years now, it has been known that a ferromagnetically-coupled
system on a lattice of corner-sharing tetrahedra can also be frustrated.
Several compounds enter a disordered magnetic state know as a Spin
ice.[^44] In these materials (Ho~2~Ti~2~O~7~ and Dy~2~Ti~2~O~7~, for
example) the crystal-field ground state of the rare-earth ion is an
Ising-like doublet with magnetic moment (\"spin\") constrained to a
local cubic \<111\> axis. In the context of the cubic lattice symmetry,
this constraint frustrates the dominant dipolar interactions in the
system and leads to frozen, non-collinear, spin disorder below \~1K. The
spin ice state is analogous to the Pauling hydrogen disorder of water
ice (H~2~O), with each spin equivalent to a hydrogen displacement vector
situated on the mid-point of an oxygen-oxygen line of contact. It is a
well-defined magnetic state, intermediate between the paramagnetic state
and the much more complex disorder that occurs in spin glasses.

Geometrically frustrated materials typically display diffuse scattering
that extends over several Brillouin zones and low energy fluctuating
spins. This often makes it difficult to distinguish between the magnetic
scattering and the other forms of diffuse scattering. For this reason
alone HYSPEC, with its polarisation analysis capabilities will be
indispensable to these studies at the SNS. However, it has many other
desirable features. The small signal associated with the spin half
systems will benefit from the high flux as well as the polarisation
capabilities. The large accessible sample space will allow us to study
these systems under the extreme conditions (ultra low temperatures and
high magnetic field) where unusual phase transitions have been observed.

Finally, many new materials are being grown and will continue to be
synthesised by chemists, and these samples are likely to be small due to
their complicated chemistry. The high flux, polarisation analysis and
the flexibility in this spectrometer will provide us with a very unique
instrument for the study of these new magnetic materials.

# Quantum Spin Systems (A. Zheludev)

Amazing progress has been made in the field of quantum low-dimensional
magnetism in the past twenty years, almost entirely driven by inelastic
neutron scattering experiments. The simplest fundamental model systems
are by now very well understood. Today the challenge is to learn about
more complex phenomena such as the effects of disorder and impurity
substitution, spin-lattice interactions and one- and two-dimensional to
three-dimensional crossover effects.

One example of a new research direction in quantum magnetism is the
problem of *random-exchange* spin chains. Consider the case of a *S=1/2*
quantum spin chain with nearest-neighbor Heisenberg exchange
interactions of random magnitude. In the simplest model, a given
percentage x of the bonds are of magnitude J~1~, and the remaining (1-x)
bonds correspond to a coupling strength J~2~, the strong and weak bonds
being distributed randomly. For a fixed x the limiting cases are easy to
understand. For J~1~\<\<J~2~ the chain breaks up into an ensemble of
finite-sized clusters: dimers, trimers, tetramers, etc. Each cluster has
a *discrete* excitation spectrum, that in a neutron experiment appears
as a series of sharp excitations at well-defined energies. For J~1~=J~2~
the situation is entirely different. In a *uniform* spin chain such as
this, the spectrum is an exotic continuum of states with no sharp
excitations and a strong wave vector dependence. The question is: how
does the spectrum look in the intermediate case of J~1~\<\~J~2~?

To date, the answer is not known, even theoretically. The main reason is
that an experimental realization of a model suitable for inelastic
neutron experiments has not been available until the recent preparation
of the new model compound BaCu~2~(Si~x~Ge~1-x~)~2~O~7~. Solid solutions
with 0\<x\<1 are characterized by susceptibility curves that can be
fitted to a Bonner-Fisher law with an intermediate value of J and are
expected to be realizations of the S=1/2 random-exchange model.
Inelastic neutron scattering experiments on BaCu~2~(Si~x~Ge~1-x~)~2~O~7~
single crystal samples are expected to provide unique insight into the
role of disorder in quantum magnets.

Previous work on the x=1 system was carried out on thermal and cold
triple-axis instruments at reactor sources as well as on the MARI time
of flight instrument at ISIS. It is clear from these measurements that
none of these instruments will be fully adequate for the study of the
solid solution BaCu~2~(Si~x~Ge~1-x~)~2~O~7~ . First of all, the
excitation bandwidth for x close to unity is expected to be of the order
of 150 meV and using a spallation source instrument becomes mandatory if
one wants to cover the relevant energy range. At the same time, the
small sample size (the largest existing crystals of BaCu~2~SiGeO~7~ are
about 4x4x10mm^3^) will require the ability to focus the incident beam
to a small spot size; a major feature of HYSPEC. Moreover, the weak and
diffuse nature of continuum scattering requires a very low and
well-controlled instrument background. Finally, to gain a detailed
understanding of the spin dynamics, polarized neutron experiments will
be needed. All of these needs will be satisfied by the proposed HYSPEC
instrument.

# THE HYSPEC SPECTROMETER

In this section we describe conceptual design, operational principles
and performance characteristics of the proposed instrument. A draft of
the HYSPEC top-level specifications with detailed and more technical
description of the spectrometer components and parameters is attached in
Appendix C.

![](media/image3.png){width="5.874409448818898in"
height="3.458267716535433in"}Our primary objective in formulating the
design of the HYSPEC spectrometer was that it deliver the highest
possible monochromatic flux to few-cm-sized samples over a broad range
of thermal and sub-thermal neutron energies \[5,90\] meV. Additionally,
we wanted to develop a design that would (i) minimize beam-related
background such as that arising from sample environments, (ii) provide
reasonably good (and easily adjustable) energy and scattering vector
resolution (δE/E \~ 0.02 - 0.15; δQ/Q \~ 0.005 - 0.1), (iii) be readily
adapted to polarization analysis, (iv) permit rapid alignment of samples
and easy installation of specialized sample environments and (v) allow
for straightforward, direct, on-line monitoring and analysis of incoming
data. Ultimately these criteria led us to the direct geometry, hybrid
concept shown schematically in Figure 3.1 and in a 3-D view on the
cover. The instrument main design parameters are summarized in Table I.

**Table I.** Instrument Parameters

  ------------------------------ ----------------------------------------
  Moderator                      Coupled, 20K, supercritical H~2~

  Incident energy                5 - 90 meV

  Energy resolution              0.02 \<∆E/E \<0.15 (for elastic
                                 scattering) depending on neutron energy
                                 and rotation rates of choppers

  Q resolution                   ∆Q/Q \~ 0.005 - 0.1

  Primary flight path            Guide with expander and compressor
                                 sections 20-25 m long

  Secondary flight path          4.5 m

  Energy defining choppers       Counter-rotating disk and Fermi
                                 choppers. Maximum rotation rate 300Hz

  Frame-overlap/order suppressor Disk choppers. Maximum rotation rate 60
  choppers                       Hz

  Flux focusing crystal          Segmeted, vertically curved PG and
                                 fluorinated mica. Heusler for polarized
                                 beam

  Sample position                1.8 m from crystal

  Beam size at sample (optimally 4 (w) x 2 (h) cm^2^
  focused)                       

  Detectors                      188 2.5cm diameter position sensitive
                                 ^3^He tubes. Horizontal pixel resolution
                                 20 min. Vertical pixel resolution 20
                                 min. Horizontal array acceptance: 60°.
                                 Vertical array acceptance: ±7.5°

  Sample environment             Will accept all standard sample
                                 environment equipment
  ------------------------------ ----------------------------------------

# Primary spectrometer (Monochromator)

Incident neutron energy will be defined by the time of flight in the
primary spectrometer. Reflection from the vertically curved
monochromator crystal in most cases will only serve to focus the beam
onto the sample. In addition, the monochromator will serve in place of
the pulse-shaping chopper, cutting the unwanted high-energy tail of the
spectral distribution of the incident neutrons, as shown in Figure 3.2.
The primary spectrometer is envisioned as consisting of a 20 to 25 meter
long guide with a center section composed of 40 mm wide by 150 mm high,
supermirror-coated, modules and with 40 mm wide expander sections at
each end, Figure 3.1. Whether the guide will be straight or slightly
curved is still an open question that will ultimately be resolved by
detailed shielding studies. Placed at intervals along the guide would be
three disk choppers; the T~0~ and frame-overlap choppers - rotating at
either the source frequency or a sub-multiple, and a counter-rotating
disk chopper pair, rotating at integral multiples of the source
frequency. A rotating drum shield containing a vertically-focusing
crystal, a beam stop (or, if a straight guide is used, a "get lost"
pipe), a vertically tapered guide, a Fermi chopper and a Soller
collimator will be placed at the guide's downstream end. Attached to the
shield - and moving with it -- would be a conventional sample rotation
stage mounted on air pads, with a 2-axes goniometer capable of
supporting large, off-center loads. In such an arrangement, neutron
energies are determined both by the beam exit angle (as defined by the
crystal and the in-shield collimator), and by the phase of rotation of
the counter-rotating chopper pair and/or the Fermi chopper relative to
the source. Apart from its energy defining function, the crystal -
together with the section of vertically tapered supermirror guide in the
drum shield -- also has the important function of efficiently focusing
the beam at the sample position.

![](media/image4.wmf){width="4.624409448818898in"
height="3.9464566929133857in"}![](media/image5.wmf){width="4.7492125984251965in"
height="3.822047244094488in"}

Each chopper has a unique role in defining the monochromatic incident
beam. The T~0~ chopper blocks the gamma rays and high energy neutrons
emitted in the earliest part of the source pulse. The frame overlap
chopper (T~3~) assures that unwanted, higher order (shorter wavelength)
neutrons are removed. Also, its rotation rate can be reduced when
necessary to block alternate source pulses in cases where the scattered
energy spectrum is so broad that spectral overlap becomes a problem. In
the main, medium-resolution, high-data-collection-rate mode of
operation, the counter-rotating disk choppers T~2~ (together with the
crystal) will define both the energy of the beam and the spectral and
time width of the pulse at the sample position, the latter being the
main factor in determining the energy resolution of the time-of-flight
analyzing section. In those cases where higher energy resolution is
needed, it is envisioned that the time width of the sample pulse would
be further reduced by the addition of a Fermi chopper (T~4~). This
chopper would have short, straight slots and a vertical axis of rotation
and be located in the shield immediately upstream of the collimator.
Like the counter-rotating disk choppers, it would rotate at integral
multiples of the source frequency.

For the focusing crystal, we propose using (for non-polarized
applications involving incident neutron energies of 5 meV and higher)
individual pyrolytic graphite (PG) plates attached to a segmented
GMI-type holder. This arrangement will provide optimal vertical focusing
over the entire 5-90 meV neutron energy range. Because a relatively
broad horizontal mosaic (probably 1.0 ^o^) will be needed for optimum
performance, we plan to use sets of three ZYA grade PG plates stacked
with spacers to slightly offset the angles between them. This so-called
"fanned arrangement" has been demonstrated to expand the horizontal
mosaic but leaves the vertical mosaic (and thus the vertical focusing
properties of the crystal) unchanged. At incident neutron energies below
5 meV, where high monochromator scattering angles hamper measurements
because of the excessively tight resolution introduced by the PG crystal
in a near backscattering geometry and space restrictions, we envision
substituting an equivalent crystal composed of fanned plates of
fluorinated synthetic mica.

1.  **Sample Stage**

As emphasized in the Scientific Objectives Section, it is important for
many of the areas of research for which HYSPEC is intended that
specialized sample environments can be easily and quickly installed.
Because the collimation upstream and downstream of the sample will
restrict the horizontal field of view of the detectors to the sample
area alone, the HYSPEC sample axis will not have to be part of the
instrument vacuum system as in other planned inelastic instruments. Thus
we expect to be able to employ conventional cryostats, magnets,
furnaces, pressure cells, etc. without creating any significant, sample-
environment-related background problems. This is another unique feature
of HYSPEC.

2.  **Secondary Spectrometer (Analyzer/Detector)**

Scattered neutron energy analysis would be done by time-of-flight alone.
We propose using a 4.5 meter radius array made up of 188
one-dimensional, position-sensitive, tube-type ^3^He detectors 2.5 cm in
diameter and 1.28 meters long, centered at the sample position. A set of
radial collimators (with horizontal angular acceptances of 20, 40, 60
and 80 minutes) interposed between the sample and detectors would
restrict their horizontal field of view to the sample area alone.
Horizontal and vertical resolutions of an individual pixel are
envisioned as being respectively 20 and 20 minutes of arc. Additionally,
the array would span a 60 degree arc horizontally and have a vertical
acceptance of ± 7.5 degrees with respect to the scattering plane. It
would be mounted on air pads on a "tanzboden" so that it could both move
with the drum shield and be rotated about the sample axis to permit
accurate positioning with respect to the monochromatic beam incident on
the sample. The detector area would most likely be gas filled and
located in a fixed, well shielded housing.

3.  **Polarization Analysis**

One of the particularly attractive features of the HYSPEC concept is
that it can quickly and easily be adapted to polarization analysis. All
that is required is that the focusing crystal used for non-polarized
studies be replaced by a crystal that both focuses and polarizes the
monochromatic beam incident on the sample and that polarization
analyzers be installed between the sample and detectors. The crystal we
propose using for polarized applications and the selection of a
polarization analyzer will be addressed in the paragraphs that follow.

1.  **The Polarizing Crystal**

Polarizing crystals are crystals of ferromagnetic materials with low
index Bragg peaks in which the nuclear and magnetic contributions to the
coherent scattering add for one of the two neutron spin states and
subtract and cancel for the other when the atomic magnetic moments are
fully aligned by an external magnetic field. Of those investigated to
date, the consensus view is that the Heusler alloy crystal Cu~2~MnAl is
the best choice in terms of both reflectivity and polarizing efficiency.
Detailed studies - such as those made, for example, by A. Freund et
al,[^45] have shown (i) that well annealed Cu~2~MnAl crystals have (111)
Bragg reflecting efficiencies that can approach those expected for
ideally imperfect crystals, (ii) that the polarization of the reflected
neutrons is in excess of 95% in crystals in which the Mn moments are
fully aligned in an external field produced by permanent magnets, and
(iii) that there is no significant loss of polarization when individual
crystal plates are mounted so as to form a cylindrically-curved,
vertically-focusing array.

We are aware that Cu~2~MnAl crystals, like all polarizing crystals, are
not without problems. One is that the procurement of crystals of good
quality has been difficult in the past. We have been advised, however,
that they can now be obtained from the ILL. A second is that the nuclear
and magnetic contributions to the (222) Bragg reflection are not
well-matched and second order contamination of the reflected beam can
significantly reduce the polarizing efficiency. Fortunately this is
ruled out as a potential problem for HYSPEC because the upstream
choppers will deliver a higher-order-free, monochromatic beam to the
crystal. And third, there is the issue of parasitic Bragg reflections
which are known to have a non-negligible impact on both the polarizing
efficiency and reflectivity and are likely to impair performance at
certain neutron energies. The time-honored way to side-step this
difficulty is simply to chose a crystal orientation that gives optimal
performance at the energy at which the spectrometer will most often be
used, in this case 15 meV, and incorporate messages into the operating
software that warn experimenters about operating at those incident
neutron energies where the polarizing efficiency and/or reflectivity is
significantly affected by parasitic reflections. Since this will
somewhat limit experimental flexibility, it is our intention to explore
the feasibility of fabricating the individual plates in the vertical
focusing array from stacks of 0.5 mm thick wafers cut from Cu~2~MnAl
single crystals. There are two potential advantages of this so-called
"composite crystal" approach. One is that composite wafer stacks are not
as spatially coherent as monolithic crystals; this reduces parasitic
reflections. The other is that introducing mosaic into the wafers by
single-axis deformation before they are bonded together creates a highly
anisotropic mosaic that improves the reflectivity without impacting the
vertical focusing.

2.  **The Polarization Analyzers**

Signal and background are typically of comparable intensity in
polarization analysis measurements. Translated into practical terms,
this means that definitive determination of the signal polarization will
only be possible if both the polarizer and polarization analyzer have
polarizing efficiencies in the 0.80--0.95 range. Heusler alloy polarizer
crystals, which produce polarizations on the order of 0.90--0.95, easily
meet this standard over the neutron energy range in which HYSPEC will
operate. Because they are of comparable efficiency and are both
well-tested and maintenance-free, our choice for analysis of the
polarization of the scattered neutron beam is the supermirror-bender
polarization analyzer. Reduced to essentials, this type of analyzer is
nothing more than a short, curved multi-channel guide with
magnetically-aligned, polarization-selective Fe-Si supermirror films on
the channel walls. Because the angles of total reflection of the + and
-- spin states differ by more than a factor of three in such films,
neutrons of one spin state tend to follow the curved channels while
those of the other continue in their original direction. The incident
beam is thus divided into divergent beams of opposite polarization. When
the beam is well-collimated and the bender optimally curved and tilted,
polarization analyzing efficiencies in the 0.80-0.95 range are easily
achieved. Moreover, at sufficient analyzer-to-detector distances the two
beams become spatially separated and both polarizations can be observed
at the same time.[^46]

To make the most effective use of the extended angular acceptance of the
HYSPEC detector array, an equivalent array of bender analyzers would
need to be installed, each directly downstream of a 20 minute angular
acceptance collimator. Like all such analyzers presently in use, we
envision that the bender channels would be formed by single crystal Si
wafers with surface coatings of Fe-Si supermirror film. For HYSPEC the
wafers would be 0.25 mm thick, 5 cm long and 14 cm high. To perform
optimally at 15 meV, they would be horizontally bent to a radius of
about 5 meters. Packed in groups of 80 into 3 cm exterior width
thin-walled aluminum alloy containers, the wafer packs would form 2 cm
wide, 80 channel benders. Room temperature single crystal Si, it should
be noted, is sufficiently transparent to neutrons in the energy range of
interest that scattering and absorption losses would not exceed 10
percent. Permanent magnets would be used to align the Fe moments in the
Fe-Si films. Assuming the closest possible packing of the containers
along an arc 55 cm from the sample axis, 19 such bender analyzers could
be positioned within the (60 degree horizontal and 15 degree vertical)
solid angle subtended by the detector array.

From the Monte Carlo (MC) simulation shown in Figure 3.3, it is evident
that the spatial profiles of the two oppositely polarized beams would be
completely separated at the detector bank 4.5 meters from the sample
axis. It is also evident in the figure that the undeflected beam will
spread over two (2.5 cm diameter) detectors and the oppositely polarized
(somewhat wider) beam following the curved channels will fall on the
adjacent ![](media/image6.wmf){width="5.374409448818898in"
height="4.761023622047244in"}three detectors. Considering that each
bender analyzer unit would be centered on a group of 10 detectors, 50
percent of the detector array would be actively collecting data in this
arrangement (which is very nearly optimum from the standpoint of
maintaining adequate spatial separation of the beams from adjacent
analyzers). Note that although each of the 19 analyzers is limited to a
specific scattering angle, rotation of the detector bank around the
sample axis will make it possible to cover - sequentially - the full
scattered neutron angular range. No more than ten rotational steps of
the detector would be needed to monitor both the flipped and unflipped
spin intensities over the full 60 degree angular range covered by the
detector array. It is also clear from the Figure 3.3 that the flipping
ratio measured in some detectors is higher than that in the others (in
which the peak of the "wrong" polarization occurs). Therefore, if the
signal is sufficiently strong, it is possible to enhance the
polarization sensitivity by restricting the counting to the detectors
with the highest flipping ratios. This is equivalent to tightening the
beam collimation after the bender-polarizer, but could be done by the
experiment analysis software without repeating the actual measurement.
Such flexibility is another attractive feature of the supermirror-bender
polarization analysis scheme proposed for HYSPEC.

Figure 3.4 shows a MC simulation of bender analyzer performance over a
range of energies on either side of 15 meV. From this it is evident that
benders designed for optimum polarizing efficiency at 15 meV will
operate with little loss of efficiency over an energy range extending
from roughly 8 to 18 meV. A second set of essentially identical bender
analyzers configured for optimum performance at 5 meV would cover the
energy range from about 3 to 8 meV with about the same efficiency,
making it possible to span the entire scattered neutron range from 3 to
18 meV.

![](media/image7.wmf){width="6.0in" height="4.8in"}Probably the most
attractive feature of using bender analyzers in a time-of-flight energy
analyzing system like HYSPEC's is the capability of monitoring *both*
scattered neutron spin states simultaneously over a relatively broad
scattered neutron energy range. But there are other attractions as well:
bender analyzers are extremely stable and, as noted above, once built
require little or no attention and are completely maintenance free.

4.  **Performance**

Of the many special features of the instrument, the most important from
the viewpoint of efficient use of source neutrons is the utilization of
the superior focusing properties of curved crystals to concentrate the
monochromatic flux on sample. To quantify the advantage of the HYSPEC
concept in this respect, a number of MCSTAS, Monte-Carlo-based,
flux-on-sample simulations were made to compare HYSPEC's flux-on-sample
with that of other proposed SNS inelastic instruments. As is evident in
Figure 3.5, despite the finite reflectivity of the PG crystal, its
superior focusing properties concentrate the monochromatic flux more
effectively than converging guides over the greatest part of the energy
range in which HYSPEC will operate. For the moderate resolution, single
crystal sample studies for which it is planned, the HYSPEC approach is
markedly superior.

![](media/image8.wmf){width="5.9992125984251965in"
height="5.022047244094488in"}

5.  **Moderator Choice**

Monte Carlo simulations have also shown that to perform optimally over
the incident neutron energy range of interest (5-90 meV), a spectrometer
of this type needs to be located on a beamline served by a coupled, 20
K, supercritical H~2~ moderator. Because optimum performance requires
that the monochromator and analyzer energy resolutions be reasonably
well matched, the length of the monochromating section should not be
much greater than 20 meters. It is also important that it ends at a
place on the SNS experimental floor where there is sufficient space to
accommodate both the rotating drum shield and the relatively extended
time-of-flight analyzer and its associated shielding. Extending the
instrument to an outside building would lead to a detrimental mismatch
between the monochromating and analyzing resolutions and a nearly
two-fold reduction of monochromatic flux at the sample position.

6.  **Additional Advantages of the HYSPEC Concept**

Apart from the features described above, HYSPEC has many other
attractive properties:

• Incident neutron energy selection and analysis of scattered neutron
energies would be primarily by time-of-flight; thus full advantage is
taken of the pulsed beam.

• Only two components -- the counter-rotating chopper pair and the Fermi
chopper --

would operate at high rotation speeds. Both would be of conventional
design and would operate well within the limits imposed by the tensile
strengths of the available materials.

• Moving the sample out of the direct beam and placing shielding between
it and the detectors is expected to reduce beam-related background to a
minimum.

• Near-forward sample scattering will be accessible to investigation.

• Depending on the type of measurement, the spectrometer operation could
be optimized for either a wide angular acceptance or a selected Q-range.

• Apart from its focusing properties, the crystal also has the important
effect of substantially reducing the (source produced) spectral
asymmetry of the beam incident on the sample: the energy resolution
function will be more symmetrical than on other instruments on coupled
moderators.

• A relatively wide primary beam (4 cm) will be available thus making it
possible to fully illuminate large as well as small samples.

• A broad and continuous range of incident neutron energies (5≤E~i~≤90
meV) will be accessible without order contamination.

• Energy resolution can be incrementally varied simply by changing the
rotation rate of the counter-rotating and /or Fermi choppers.

• By changing the collimation of the incident monochromatic beam or the
angular acceptance at the analyzer (or both) the longitudinal
Q-resolution can easily be varied.

• Various kinds of monochromating crystals with a variety of focussing
options could be employed such as, for example, two-dimensional
focussing, asymmetrically-cut, perfect crystal focussing, etc.

7.  **Future Considerations**

Yet to be addressed in detail are two design issues. The first and most
important relates to keeping the background to a minimum: a choice will
have to be made between a curved guide with a beam stop inside the
monochromator drum shield and a straight guide with a "get-lost" pipe
with the beam stop a considerable distance from the data collecting
area. The second issue is purely mechanical: the large (and heavy)
analyzer of the spectrometer will have to be rigidly coupled to the
large (and heavy) monochromator drum shield and move with it when the
incident energy is changed. Additionally, the detector array will have
to rotate in a precise and reproducible fashion about the sample axis.
This, however, does not seem to pose any conceptual difficulty, as
similar task is successfully accomplished in the design of several
existing modern neutron spectrometers, such as FOCUS at Swiss Spallation
Neutron Source SINQ, or a Spin-Echo machine recently commissioned at
NIST Center for Neutron Research. There is also a location constraint:
because the proposed secondary flight-path is sufficiently long
(nominally 4.5 m), and in addition the sample axis is offset from the
primary beam (1.8 m), the combined drum shield, analyzer and associated
analyzer shielding will require an ample amount of space on the
experimental floor and limit the choice of beam lines.

3.  **INSTRUMENT DEVELOPMENT TEAM**

    1.  **Membership and composition**

The HYSPEC Instrument Development Team was formed following the Workshop
on the Hybrid Spectrometer for the SNS held at BNL in October of 2001.
Most of the IDT members participated in the workshop and have
subsequently contributed to developing the HYSPEC science case, as well
as to the technical issues, presented in this proposal. The IDT
membership is open to qualified applicants upon a 2/3 majority vote of
the Executive Committee.

The members of the IDT come from a variety of national and international
universities and laboratories and are listed below. All have a common
interest in the investigation of low energy, atomic-scale dynamical
properties of crystalline solids. The IDT includes many senior members
of the condensed matter community with well-established scientific
credentials such as Tranquada, Lander, Shirane, Rhyne, etc. who expect
to use HYSPEC to continue their research programs. The IDT also includes
younger faculty members such as Lee, Greven, Kiryukin, Hirota who are
still in the process of building their scientific programs and intend to
use HYSPEC as one of their main research tools. Other members of the IDT
have particular areas of expertise, which are vital to the project. For
example, Majkrzak and Regnault are leading experts in polarized neutron
beams; the Ames group (Stassis) has extensive experience in building
large mechanical structures; and LANL (Daemen) is a leader in Monte
Carlo simulations and has extensive experience in software development.

2.  **Organization and mission**

The efforts of the Instrument Development Team are coordinated by the
Executive Committee, which is headed by the Principal Investigators, S.
Shapiro and I. Zaliznyak. It is expected that the membership in the
Executive Committee will evolve as the project progresses. As is
illustrated in the schematic organizational structure presented in
Fig.5.1, the PI's and the Executive Committee closely interact with the
SNS Instrument Systems Group and report to the DOE BES. SNS Instrument
Scientist, D. Abernathy, currently serves as a liaison between the IDT
Executive Committee and the SNS Instrument Systems Group. Based upon its
expertise, the IDT provides input to the instrument design, engineering,
construction and scientific program through the work of the various
Topical Advisory Teams (TAT) with experience in polarized beams,
detector technology, software, etc. These TAT's are coordinated by the
Executive Committee. The IDT's ultimate mission is to ensure that the
world's best state of the art instrument is built and commissioned at
the SNS and will produce world class science.

> **Executive Committee:**

[S. M. Shapiro]{.underline}, co-PI BNL

[I. Zaliznyak]{.underline}, co-PI BNL

J. Tranquada BNL

L. Passell BNL

C. Stassis Ames Lab/Iowa St. University

D. Abernathy SNS

> **IDT Members with their institutional affiliations:**

J. Gardner BNL

V. J. Ghosh BNL

G. Shirane BNL

G. Xu BNL

L. Daemon Los Alamos

M. Greven Stanford University

B. Gaulin McMaster University

K. Hirota ISSP

V. Kiryukhin Rutgers University

G. Lander EITU

Y. Lee MIT

C. Majkrzak NIST

S. Nagler ORNL

R. Osborn Argonne

L. P. Regnault CEN-Grenoble

J. Rhyne Missouri University

A. Zheludev ORNL

4.  **PROJECT MANAGEMENT PLAN**

A schematic of the proposed project organizational structure is
presented in Figure 5.1. We propose that the project is directed by the
HYSPEC Executive Committee headed by the Principal Investigators in
close coordination with the SNS Instrument Systems Group. The PI's, on
behalf of the IDT Executive Committee, will interact closely with the
SNS Experimental Facilities Division and report to the DOE BES. They
will also interact with the SNS to establish the framework for the
practical implementation of the project which will be documented in the
form of the HYSPEC Top Level Specifications (TLS). The draft version of
the TLS is attached in Appendix C. The final working version will be
negotiated, agreed, and co-signed by the SNS and the HYSPEC IDT
management.

In the proposed plan the Center for Neutron Science (CNS) at Brookhaven
National Laboratory continues to play a central role in the HYSPEC
project. This is natural in view of the role it has played in designing
and developing the spectrometer and also benefits BNL's Neutron
Scattering Group. We believe that such a role also benefits the national
neutron effort by diversifying the DOE's neutron instrumentation
capabilities. At the same time we understand that a final decision on
the structure of the Management Plan remains to be made.

In our plan the HYSPEC Instrument Scientist (FTE) and a Project Engineer
(FTE) would be subcontracted to the BNL Center for Neutron Science in a
manner consistent with the DOE BES policy concerning the SNS Instrument
Construction Projects. They will be responsible for the project
oversight and day-to-day operations as a project manager and an
assistant project manager, respectively. They will work with the
component teams of the SNS Instrument Systems Group and under the
supervision of the IDT Executive Committee, and will report to the
HYSPEC PI's. An additional workforce at BNL in the form of the
postdoctoral research associates and/or the part-time assistants will be
funded as necessary for the instrument design and engineering studies,
software development, scientific program development, etc. Engineering
and technical resources of the SNS Instrument Team at Argonne National
Laboratory and SNS/ORNL will be subcontracted as needed for the design,
engineering, fabrication and installation of the instrument components
and consistent with the DOE policy.

The project management responsibilities will include (i) preparing the
detailed design specifications of the instrument systems and components
following the IDT guidance and in compliance with the TLS; (ii)
preparing the detailed budget estimates, asking for bids, and
negotiating with the subcontractors for the outsourced components; (iii)
working with the SNS to oversee the in-house fabricated components
subcontracted to the SNS Instrument Systems Group and closely coordinate
the purchase orders for the externally outsourced components to maximize
the economy of scale wherever possible; (iv) overseeing the installation
and integration of the instrument systems; (v) directing the software
development; (v) participating in the instrument commissioning and user
scientific program development. The Instrument Scientist will also
interact with the DOE BES and the SNS to report on significant
developments and issues, and to fulfill the general reporting and other
requirements appropriate for a construction project.

5.  **ESTIMATED BUDGET AND TIME SCALE**

The HYSPEC cost summary is shown in Table II, a detailed budget estimate
and funding profile are presented in Appendix D. The budget was
estimated after consultations with the SNS Instrument Systems Team and
using the SEQUOIA[^47] and ARCS[^48] proposed budgets as guidelines for
items which would be common to HYSPEC, such as shielding, detectors,
choppers, etc. There has been minimal engineering input for HYSPEC so
far, which will be vital to firm up these costs. Therefore, this budget
is preliminary and will be modified after more detailed engineering and
design studies are undertaken. To this end, we are initially asking for
\$130K in FY03 and \$400K in FY04 to hire a project engineer and a
project scientist who would direct the essential engineering that is
needed for a Conceptual Design Report (CD1).

The HYSPEC estimated cost is \$15,750K in FY03 dollars, including burden
and contingency. Escalated to as spent dollars, the cost would be
\$18,239K at end of project. This covers construction of an optimized
instrument located within the experimental hall. However there is
concern expressed by the SNS Instrument Systems Team leader that the
siting of HYSPEC will interfere with neighboring beam lines, which have
not yet been allocated. One possibility is to locate HYSPEC in a
separate building outside of the experimental hall. This will result in
additional costs due to the building and the extra guides and shielding
that will be needed. A rough estimate is \$3M for the building and an
additional \$1.25M for the guides and shielding. The IDT is concerned,
however, that extending the instrument will severely compromise its
performance: at a fixed analyzer resolution an increase in the primary
flight-path results in roughly proportional decrease in the
flux-on-sample; calculations are underway to establish the performance
of such an extended instrument more precisely (see also Appendix C).

The profile given in Table II is five years from the onset of funding
based upon estimates for ARCS and SEQUOIA. However, because of the
limited engineering studies that have been performed it is likely that
the funding profile would be extended to 6 or 7 years to allow for the
initial engineering studies. It will also be necessary to discuss with
SNS the practical timing of spectrometer installation.

The budget includes a substantial funding, 200k\$ per year, for
scientific program development. This is necessary not only to ensure
that the HYSPEC IDT remains at the forefront of neutron research but
also that new opportunities provided by the SNS and the HYSPEC
spectrometer are developed and utilized to the fullest extent. It is
also needed to ensure that the young scientists who will form the core
of the future user community have opportunities for appropriate
scientific development. The scientific program will be developed under
the supervision of the IDT members. This funding will be used to hire
postdoctoral fellows who will participate in spectrometer development
and will be involved in research using existing chopper spectrometers
around the world, to pay for travel and sample preparation for the
experiments, etc.

Finally, there have been recent communications between the co-PI
(Shapiro) and the French IDT member, L.P. Regnault, who has stated that
the French Atomic Energy Commission (CEA) is considering a possibility
of participating in HYSPEC project by providing some funds for it.
Obviously, we are vigorously pursuing this.

**Table II. HYSPEC Estimated Cost and Funding Profile**

  ---------------- ------------------ ------------- ------------ ---------- ----------- ----------- ----------- ----------- ------------
                                      **FY03 Cost   **At Year                                                                
                                      Estimate**    Funding                                                                 
                                                    Required**                                                              

                   **ITEM**                         **FY03**     **FY04**   **FY05**    **FY06**    **FY07**    **FY08**    **Total**

  **Technical                                                                                                               ** **
  Construction**                                                                                                            

                   Primary Flight     3,300         0            0          1,603       1,930       0           0           3,533
                   Path                                                                                                     

                   Monochromator      2,560         0            0          380         2,385       0           0           2,765
                   Section                                                                                                  

                   Sample Stage       350           0            0          158         108         111         0           378

                   Detector System    3,440         0            0          717         2,993       0           0           3,710

                   Data Collection    400           0            256        0           11          11          148         426
                   System                                                                                                   

                   Installation Labor 1,400         0            0          0           0           445         1,140       1,585

                   Technical          11,450        0            256        2,858       7,427       567         1,288       12,398
                   Construction Total                                                                                       

                                                                                                                            

  **Project                                                                                                                 
  Management &                                                                                                              
  Engineering**                                                                                                             

                   Project Management 800           0            164        169         173         178         182         867

                   Engineering &      2,500         405          513        522         537         384         296         2,657
                   Design                                                                                                   

                   Proj. Mgt & Engrg. 3,300         380          615        628         645         940         1,551       4,758
                   Total                                                                                                    

                                                                                                                            ** **

  **Project TEC**                     **14,750**    **380**      **871**    **3,486**   **8,072**   **1,507**   **2,839**   **17,156**

                                                                                                                            ** **

  **Other Costs**                     **1,000**     **0**        **205**    **211**     **217**     **222**     **228**     **1,083**

                                                                                                                            ** **

  **Total Project                     ** 15,750**   ** **        ** **      ** **       ** **       ** **       ** **       **18,239**
  Cost (TPC)**                                                                                                              
  ---------------- ------------------ ------------- ------------ ---------- ----------- ----------- ----------- ----------- ------------

**Appendix A. CV of the HYSPEC IDT Members**

Stephen M. Shapiro

**Name and Date of Birth:** Stephen M. Shapiro

June 21, 1941   

**Address** Brookhaven National Laboratory

Department of Physics

Upton, NY 11973

631-344-3822

<shapiro@bnl.gov>

**Education:** 1969, Ph.D.Johns Hopkins University

> Thesis: Light Scattering Study of Alpha-Beta Transition in Quartz; H.
> Z. Cummins, advisor
>
> 1963, B.S., Union College

**Employment** 2001-present, Director of Center for Neutron Science

> 2000-present,Senior Physicist
>
> 1994-2000: Head of Solid State Physics
>
> 1994: Visiting Professor, Univeristy of Grenoble
>
> 1986-1987: Distinguished Visiting Scientist, Laboratoire Léon
> Brillouin, Saclay, France
>
> 1983: Yamada Fellowship, University of Osaka, Japan
>
> 1975-2000: Physicist (with tenure, 1984), Brookhaven
>
> 1972-1975: Associate Physicist, Brookhaven
>
> 1971-1972: Research Associate, Brookhaven
>
> 1969-1972: Postdoctoral Fellow, University of Paris

**Professional Societies:** American Physical Society

Materials Research Society (MRS)

Neutron Scattering Society of America (NSSA)

> **Committees** Program AdvisorCommittees for IPNS and LANSCE
>
> Chaired Program Review Committee of AECL, Chalk River, Canada
>
> Past Treasurer, Neutron Scattering Society of America (NSSA)
>
> US-Japan Steering Committee Member
>
> Divisional Associate Editor for Physical Review Letters
>
> Member of Scientific Advisory Committee of CEA, France

# Chair, Review Committee for CEA-Grenoble, Neutron Program

**Awards and Honors:** Fellow of the American Physical Society 1986

DOE Award for Outstanding Scientific Accomplishment in 1988 for work on
Premartensitic Behavior in metallic alloys

**Publications:**          1. *Optical Response of
High-Dielectric-Constant Perovskite-Related Oxide*, C. C. Homes, To.
Vogt, S. M. Shapiro, A. P. Ramirez, Science **293**, 673 (2001).

> 2*.Field-Induced Three- and Two-Dimensional Freezing in a Quantum Spin
> Liquid,* Y. Chen, Z. Honda, A. Zheludev, C. Broholm, K. Katusmata, and
> S. M. Shapiro, Phys. Rev. Lett. **86**, 1618 (2001).
>
> 3.*Electron Diffraction Studies of Phonons and Static Disorder in
> SrTiO~3~*, R. Wang, Y. Zhu, and S. M. Shapiro, Phys. Rev. B 621, 8814
> (2000).
>
> 4*.Neutron Scattering Studies of Pre-transitional Effects in
> Solid-Solid Phase Transformations* S. M. Shapiro, Proceedings of
> PTM-99, Kyoto, May 1999 (Japan Institute of Metals Proceedings,
> **12**, 799 (2000)
>
> 5\. *Structural Defects and the Origin of the Second Length Scale in
> SrTiO~3~*, R. Wang, Y. Zhu, and S. M. Shapiro, Physical Review Letters
> **80**, 2370 (1998)

Igor A. Zaliznyak

**Date of Birth:** 05/01/1965** **

**Professional Address:**  Physics Department, Brookhaven National
Laboratory (BNL), Upton, NY 11973-5000, USA.

> Tel.: (631) 344 3761; Fax: (631) 344 2739
>
> Email: <zaliznyak@bnl.gov>; <igor@neutrons.phy.bnl.gov>

**Education:** Ph. D. in Physics (1993), P. Kapitza Institute for
Physical Problems, Moscow, Russia. Thesis title: *Experimental study of
the magnetostatic and resonance properties of quasi-one-dimensional
antiferromagnets*. Thesis supervisors: L. A. Prozorova and L.-P.
Regnault

**Employment:** Associate Physicist, 2001 -- present; Assistant
Physicist, 1999-2001, Neutron Scattering Group, Brookhaven National
Laboratory, Upton, NY

> Postdoctoral Research Fellow, 1996-1999, Department of Physics and
> Astronomy, Johns Hopkins University, Baltimore, MD
>
> Visiting researcher, 11/1995-01/1996; 08/1994-09/1995, Laboratoire de
> Magnetisme et Diffraction des Neutrons, SPSMS/DRFMC, CEN-Grenoble,
> France
>
> Scientist, 1995-; Junior Scientist, 1993-1995, P. Kapitza Institute
> for Physical Problems, Moscow, Russia.
>
> Visiting (graduate) researcher, 12/1991-06/1993, Laboratoire de
> Magnetisme et Diffraction des Neutrons, SPSMS/DRFMC, CEN-Grenoble,
> France

**Professional Societies:** Member, American Physical Society (APS),
Neutron Scattering Society of America (NSSA)

**Committees:** Member, SNS-HIFR User Group, Oak Ridge National
Laboratory, TN; Member, Solid State Future Planning Committee, BNL

**Awards and Honors:** Presidential fellowship for outstanding young
researcher, Moscow, Russia, 1993-1995; \"Red\" diploma of excellence,
Moscow Institute of Physics and Technology, Russia, 1988

+--------------------+-------------------------------------------------+
| **Recent           | -   A. Zaliznyak, C. Broholm, M. Kibune, H.     |
| Publications:**    |     Takagi, \"Spin Freezing In The Cuprate      |
|                    |     S=1/2 Antiferromagnetic Chain Compound      |
|                    |     SrCuO~2~", cond-mat/9812440 (1998); Phys.   |
|                    |     Rev. Lett. **83**, 5370 (1999).             |
|                    |                                                 |
|                    | -   I. A. Zaliznyak, J. P. Hill, J. M.          |
|                    |     Tranquada, R. Erwin, Y. Moritomo            |
|                    |     \"Independent freezing of charge and spin   |
|                    |     dynamics in                                 |
|                    |     La~1.5~Sr~0.5~CoO~4~\",cond-mat/0006115,    |
|                    |     Phys. Rev. Lett. **85**, 4353 (2000).       |
|                    |                                                 |
|                    | -   I. A. Zaliznyak, S.-H. Lee, S. V. Petrov,   |
|                    |     \"Continuum in the spin excitation spectrum |
|                    |     of a Haldane chain, observed by neutron     |
|                    |     scattering in CsNiCl~3~\" cond-mat/0010049; |
|                    |     Phys. Rev. Lett. **87**, 017202 (2001).     |
|                    |                                                 |
|                    | -   M. B. Stone, I. Zaliznyak, D. H. Reich      |
|                    |     and C. Broholm, \"Frustration-Induced Two   |
|                    |     Dimensional Quantum Disordered Phase in     |
|                    |     Piperazinium Hexachlorodicuprate\",         |
|                    |     cond-mat/0104150; Phys. Rev. B **64**,      |
|                    |     144405 (2001).                              |
|                    |                                                 |
|                    | -   I. A. Zaliznyak, J. M. Tranquada, R.        |
|                    |     Erwin, Y. Moritomo, \"Spin-entropy driven   |
|                    |     melting of the charge order in              |
|                    |     La~1.5~Sr~0.5~CoO~4~\" , cond-mat/0105404;  |
|                    |     Phys. Rev. B **64**, 195117 (2001).         |
|                    |                                                 |
|                    | -   I. A. Zaliznyak, \"Continuum Spin           |
|                    |     Excitations in S=1 one-dimensional          |
|                    |     antiferromagnet\", cond-mat/0109065; J.     |
|                    |     Appl. Phys. 91 812210MMM (2002).            |
+--------------------+-------------------------------------------------+

**JOHN M. TRANQUADA**

**Birth Date:** Oct. 5, 1955

**Address:** Physics Department

Brookhaven National Laboratory

Upton, NY 11973-5000

> Phone: (631) 344-7547

Fax: (631) 344-2918

E-mail: jtran@bnl.gov

**Educational Background:** B.A., cum laude, in Physics, Pomona College,
1977

> Ph.D. in Physics, University of Washington, 1983
>
> Thesis: \"X-ray Absorption Studies of Solids at High Pressure\";
>
> Advisor: Robert Ingalls

**Professional Experience:**

*1983-1986*: Postdoctoral Research Associate, North Carolina State
University and Brookhaven National Laboratory

*1986-1988*: Assistant Physicist, Brookhaven National Laboratory

*1988-1990*: Associate Physicist, Brookhaven National Laboratory

*1990-2000*: Physicist, Brookhaven National Laboratory (with tenure
since 1992)

*1998-present*: Leader of Neutron Scattering Group, Brookhaven National
Laboratory

*2000-present*: Senior Physicist, Brookhaven National Laboratory

**Professional Affiliations:**

Fellow, American Physical Society

Member, American Association for the Advancement of Science

**Other Professional Activities:**

Member of the Steering Committee for the US-Japan Cooperative Research
Program on Neutron Scattering, 1999-

BESAC Subpanel on Neutron Scattering, 2000

BESAC Subpanel Review of IPNS and MLNSC, 2000

SNS-HFIR User Group (SHUG) Executive committee, 2000-present Vice-Chair,
2001; Chair, 2002

Divisional Associate Editor, Physical Review Letters, 2001-present

Lehman Review Committee for the Spallation Neutron Source, 2001-present

Member of the Program Advisory Committee for NCNR (NIST), 2001-present

Member of the Proposal Review Committee for HFIR (ORNL), 2002

**Honors and Awards:**

DOE Award for Outstanding Scientific Accomplishment in Solid State
Physics, 1988

Fellow of the American Physical Society, 1997

BNL R&D Award, 1997

**Recent Publications**

1.  V. J. Emery, S. A. Kivelson, and J. M. Tranquada, "Stripe Phases in
    High Temperature Superconductors,\'\' *Proc. Natl. Acad. Sci.
    U.S.A.* **96**, 8814-7 (1999).

2.  N. Ichikawa, S. Uchida, J. M. Tranquada, T. Niemller, P. M.
    Gehring, S.-H. Lee, and J. R. Schneider, "Local Magnetic Order vs.
    Superconductivity in a Layered Cuprate,\'\' *Phys. Rev*. *Lett*.
    **85**, 1738-41 (2000).

3.  I. A. Zaliznyak, J. P. Hill, J. M. Tranquada, R. Erwin, and Y.
    Moritomo, "\`Independent freezing of charge and spin dynamics in
    La~1.5~Sr~0.5~CoO~4~," *Phys. Rev. Lett*. **85**, 4353 (2000)

.

4.  J. M. Tranquada, K. Nakajima, M. Braden, L. Pintschovius, and R. J.
    McQueeney, \`\`Bond-Stretching-Phonon Anomalies in Stripe-Ordered
    La~1.69~Sr~0.31~NiO~4~,\'\' *Phys. Rev. Lett.* **88**, 075505
    (2002).

5.  S.-H. Lee, J. M. Tranquada, K. Yamada, D. J. Buttrey, Q. Li, and
    S.-W. Cheong, \`\`Freezing of a Stripe Liquid,\'\' *Phys. Rev.
    Lett.* **88**, 126401 (2002).

Jason Stewart Gardner

**Personal Data** Born: August 27^th^ 1970, Liverpool, England

Nationality: British

**Address** NIST Center for Neutron Research

> Building 235, Rm A-118
>
> National Institute of Standards and Technology
>
> Gaithersburg, MD 20899-8562
>
> Phone: (301) 975-8391\
> Fax:    (301) 921-9847
>
> Email: <jason.gardner@bnl.gov>

## University Qualifications

91. B. Sc. (Physics),University of Warwick,

> Coventry, England.

92. MSc. (Physics), Keele University,

> Staffordshire, England.

For a course entitled "Optical Data Recording"

### 

###  Ph.D. (Physics), University of Warwick,

> Coventry, England

### 

### Thesis Title: "Neutron Scattering, SR and Magnetic Studies of Compounds Related to High Temperature Superconductors."

### Thesis Supervisor: Professor Donald M^c^Kenzie Paul

**Professional Employment**

## 

##  (Nov 2002 -- Present)

> I am currently an assistant physicist for the Brookhaven National
> Laboratory. I am part of the Brookhaven / National Institute of
> Standards and Technology (NIST) alliance to promote research,
> specifically neutron scattering, in the USA. My work will involve the
> study of prototypical magnets and structural materials using elastic
> and inelastic neutron scattering, as well as other tools that will
> help elucidate the properties being studied.

###  (1999 -- 2002):

> Research Associate, National Research Council, Chalk River
> Laboratories, Chalk River, CANADA.

###  (1998 -- 1999):

> Postdoctoral Fellow, Los Alamos National Laboratory, USA.

Supervisors: Drs. D. Argyriou and R. H. Heffner

###  (1996 -- 1998):

> Research associate, Department of Physics and Astronomy, McMaster
> University, Canada. Supervisor: Prof. B. D. Gaulin

###  (Summer 1990):

> Summer research assistant at the University of Oporto, Portugal. My
> work included measuring the thermopower and resistance of highT~c~
> superconductors. Supervisor: Prof. J. B. Sousa

## Awards/Grants

**2002**

Three Researcher Exchange Awards between the NRC and the British Council
\$6.5k

NATO science Programme Collaborative Linkage Grant 10k EURO

**2001**

**Technology Investment Fund (TIF) with Dr. Calvin Hyatt**

**- Design of Magnetic Shape Memory Alloys for 3 years \$250k/yr (3
yrs)**

Travel grant to Taiwan under the NRC\'s Eminent Researchers Program.
\$5k

Two Researcher Exchange Awards between the NRC and the British Council
\$4.6k

**2000**

NSERC Major equipment Grant with M. Collins (McMaster University)

> 9 Tesla, 300 mK superconducting magnet for neutron studies \$260k

#### SELECTED PUBLICATIONS

\"Evidence for Quantum Dynamics in \"Hot\" Spin Ice\"

G Ehlers, A L Cornelius, M Orendáč, M Kajňaková, T Fennell, S T Bramwell
and **J. S. Gardner**

Accepted to J. Phys. Cond. Matter (Nov, 2002).

\"Pressure Induced Crystallization of a Spin Liquid\"

I Mirebeau, I N Goncharenko, P Cadavez-Peres, S T Bramwell, M J P
Gingras and **J S Gardner**

NATURE **420**, 54 (2002).

\"Magnetic structure of antiferromagnetic NdRhIn5\"

S Chang, P G Pagliuso, W Bao, **J S Gardner**, I P Swainson, J L Sarrao,
and H Nakotte

Phys. Rev. B **66,** 132417 (2002).

Magnetization distribution in the Layered Colossal Magnetoresistance
Manganite La~1.2~Sr~1.8~Mn~2~O~7~ from Polarized Neutron Diffraction\"

D.N. Argyriou, P.J. Brown, **J S Gardner** and R.H. Heffner

Phys. Rev. B **65,** 214431 (2002).

\"Neutron scattering studies of the cooperative paramagnet pyrochlore
Tb~2~Ti~2~O~7~\"

**J S Gardner**, B D Gaulin, A J Berlinsky, P Waldron, S R Dunsiger, N P
Raju and J E Greedan

Phys. Rev. B **64**, 224416 (2001).

\"Order in the Heisenberg pyrochlore: The magnetic structure of
Gd~2~Ti~2~O~7~\"

J D M Champion, A S Wills, T Fennell, S T Bramwell, **J S Gardner** and
M A Green

Phys. Rev. B **64,** 140407**(R)** (2001).

\"Spin Correlations in Ho~2~Ti~2~O~7~: a Dipolar Spin Ice System\"

S T Bramwell, M J Harris, B C Den Hertog, M J P Gingras, **J S
Gardner**, D F McMorrow, A R Wildes, A Cornelius, J D M Champion, R G
Melko and T Fennell

Phys. Rev. Lett. **87,** 047205 (2001).

\"Low Temperature Spin Dynamics of the Geometrically Frustrated
Antiferromagnet Gd~3~Ga~5~O~12~\"

S Dunsiger, **J S Gardner** , J Chakhalian, R Kiefl, R Movshovich W A
MacFarlane, R I Miller, J E Sonier and B D Gaulin

Phys. Rev. Lett., **85**, 3504 (2000).

\"Magnetic and Thermodynamic Properties of the Collective Paramagnetic
State in the Pyrochlore Antiferromagnet Tb~2~Ti~2~O~7~\"

M J P Gingras, B C den Hertog, M Faucher, **J S Gardner**, S Dunsiger, L
J Chang, B D Gaulin, N P Raju and J E Greedan

Phys. Rev. B, **62**, 6496 (2000).

\"Glassy Statics and Dynamics in the Chemically Ordered Pyrochlore
Antiferromagnet Y~2~Mo~2~O~7~\"

**J S Gardner**, B D Gaulin, S H Lee, C Broholm, N P Raju and J E
Greedan

Phys. Rev. Lett., **83**, 211 (1999).

**VINITA J. GHOSH**

**Address:** Monte Carlo Simulations

> 7 Dartmouth Road, Shoreham, NY 11786
>
> Home phone: (631) 744-6962
>
> Office phone: (631) 344-6226
>
> E-mail: ghoshvj@bnl.gov

**Education:** 1969 B.Sc. Physics University of Delhi, New Delhi, India

1971 M.Sc. Physics University of Delhi, New Delhi, India

1979 Ph.D. Physics University of Rochester, Rochester, NY

Advisor: Robert S. Knox, Topic: Theory of hole transport in rare gas
solids

# 

# Employment History: Physical Review and physical review Letters: 1980-1981

Brookhaven National Laboratory: 1981-2000

Consultant to Brookhaven National Laboratory: 2001-now

## Selected Publications:

V. J. Ghosh, M. McKeown, D. O. Welch, and K. G. Lynn. An *ab initio*
Monte Carlo study of low energy positron and electron implantation in
elemental metals and multilayers. Nucl. Instrum. Methods in Physics
Research [B90]{.underline}, 442-5 (1994).

V. J. Ghosh. Positron implantation profiles in elemental and multilayer
systems. Appl. Surf. Sci. [85]{.underline}, 187-95 (1995).

V. J. Ghosh and G. C. Aers. Positron stopping in elemental systems:
Monte Carlo calculations and scaling. Phys. Rev. B [45]{.underline}(1),
45-59 (1995).

K. A. Ritley, V. J. Ghosh, K. G. Lynn, M. Mckeown, and D. O. Welch. The
SPRITE and POS-SPRITE user report: An extensible calculation of positron
and electron implantation in solids, BNL-64884, Informal Report, (1997).
This User Report is part of a package submitted to the DOE Science and
Technology Software Center. It accompanies a collection of programs
developed at BNL to calculate the trajectories of positrons and
electrons in solids. These programs include the calculation of
scattering cross-sections relating to positron and electron energy loss
and thermalization in metals and small band-gap semiconductors.

Vinita J. Ghosh, Bent Nielsen, and Thomas Friessnegg. Identifying
open-volume defects in doped and undoped perovskite-type LaCoO~3~ ,
PbTiO~3~ , and BaTiO~3~ . Phys. Rev. **B61**, 207, (2000).

V.J. Ghosh, M. Alatalo, P. Asoka-Kumar, B. Nielsen, K.G. Lynn, A.C.
Kruseman, and P.E. Mijnarends, Calculation of the Doppler broadening of
the electron-positron annihilation radiation in defect-free bulk
materials. Phys. Rev. **B61**, 10092, (2000).

Vinita J. Ghosh, John Z. Larese, L.L. Daemen, and P.A. Seeger. Monte
Carlo simulations of the HERMES spectrometer. (2000), (unpublished).

L.L. Daemen, V.J. Ghosh, L. Passell, and P.A. Seeger. A Proposed
Q-Selective Time-of-Flight Spectrometer for Inelastic Neutron Scattering
at the SNS, (2000) (unpublished).

# Martin Greven

**Name and Date of Birth:** Martin Greven, 2/19/67

**Address :** T.H Geballe Laboratory for Advanced Materials

> McCullough Building, Room 344
>
> 476 Lomita Mall
>
> Stanford University
>
> Stanford, CA 94305-4045
>
> Tel: (650) 725 8978
>
> Fax: (650) 724 3681
>
> E-mail: greven@stanford.edu

**Research Interests:** Neutron and x-ray scattering of strongly
correlated electron systems.

> High-temperature superconductivity. Low-dimensional magnetism. Crystal
> growth and characterization. Quantum Monte Carlo simulations of model
> magnets.

**Education:** 1988: Vordiplom, Universität Heidelberg, Germany.

> 1988-89: Exchange Scholarship, University of Massachusetts, Amherst.
>
> 1989-95: Ph.D., Physics Department, Massachusetts Institute of
> Technology, with Prof. R.J. Birgeneau. Thesis title: \"Neutron
> Scattering Study of Magnetism in Insulating and Superconducting
> Lamellar Copper Oxides.\"

**Employment:** 1995-97: Post-doc with Prof. R.J. Birgeneau,
Massachusetts Institute of

> Technology.
>
> 1998-present: Assistant Professor, Department of Applied Physics and
>
> Stanford Synchrotron Radiation Laboratory, Stanford University.

**Professional Societies:** American Association for the Advancement of
Science

> American Physical Society
>
> Neutron Scattering Society of America
>
> Materials Research Society

**Awards and Honors:** 1988-89: Exchange Scholarship, University of
Massachusetts.

> 1999-01: Alfred P. Sloan Fellow

**Selected Publications:** O.P. Vajk, P.K. Mang, M. Greven, P.M.
Gehring, and J.W. Lynn, \"Quantum impurities in the two-dimensional spin
one-half Heisenberg

> antiferromagnet,\" Science 295, 1691 (2002).
>
> Y.J. Kim, A. Aharony, R. J. Birgeneau, F.C. Chou, O. Entin\--Wohlman,
> R.W Erwin, M. Greven, A.B. Harris, M.A. Kastner, I.Y. Korenblit, Y.S.
> Lee, and G. Shirane, \"Ordering due to quantum fluctuations in Sr_2
> Cu_3 O_4 Cl_2,\" Phys. Rev. Lett. 83, 852 (1999).
>
> R.J. Birgeneau, M. Greven, M.A. Kastner, Y.S. Lee, B.O. Wells, Y.
> Endoh, K. Yamada, and G. Shirane, \"Instantaneous spin correlations in
> La_2 Cu O_4,\" Phys. Rev. B 59, 13788 (1999).
>
> H. Kimura, K. Hirota, H. Matsushita, K. Yamada, Y. Endoh, S.\--H. Lee,
> C.F. Majkrzak, R. Erwin, G. Shirane, M. Greven, Y.S. Lee, M.A.
> Kastner, and R. J. Birgeneau, Neutron scattering study of static
> antiferromagnetic correlations in La_2-x Sr_x Cu_1-y Zn_y O_4,\" Phys.
> Rev. B 59, 6517 (1999).
>
> K. Yamada, C.H. Lee, K. Kurahashi, J. Wada, S. Wakimoto, S. Ueki, H.
> Kimura, Y. Endoh, S. Hosoya, G. Shirane, R.J. Birgeneau, M. Greven,
> M.A. Kastner, and Y.J. Kim, \"Doping dependence of the spatially
> modulated dynamical spin correlations and the superconducting
> transition temperature in La_2-x Sr_x Cu O_4,\" Phys. Rev. B 57, 6165
> (1998).
>
> M. Greven, R. J. Birgeneau, Y. Endoh, M. A. Kastner, B. Keimer, M.
>
> Matsuda, G. Shirane, and T. R. Thurston, \"Spin correlations in the 2d
>
> Heisenberg antiferromagnet Sr_2 Cu O_2 Cl_2: Neutron scattering, Monte
> Carlo simulation, and theory,\" Phys. Rev. Lett. 72, 1096 (1994).

# VALERY KIRYUKHIN

**Name and Date of Birth:** Valery Kiryukhin, 03/22/1970.

**Address:** Dept. of Physics & Astronomy

Rutgers University

Piscataway, NJ 08854

\(732\) 445-3899

vkir@physics.rutgers.edu

**Education:** Ph.D. (Physics), Nov 1997, Princeton University,
Princeton, NJ

M.S., Sep 1992, Moscow Institute of Physics and Technology,

Moscow, Russia

Ph.D. Thesis Title: Magnetism and Electron-Lattice Interaction:

X-ray Scattering Study of Spin-Peierls and Colossal

Magnetoresistance Systems

Ph.D. Thesis Advisor: B. Keimer

**Employment:** Sep 1992-Aug 1997 Princeton University, Research
Assistant

Sep 1997-Aug 1999 MIT, Postdoctoral Research Assistant

Sep 1999-present Rutgers University, Assistant Professor

**Professional Societies:** American Physical Society

**Committees**: 1. Program Committee, 46th Annual Conference on
Magnetism and

Magnetic Materials, July 2001.

2\. Proposal Study Group, Cooperative Grunts Program,

> U.S. Civilian Research and Development Foundation, May 1996.

**Awards and Honors:** 2001 Alfred P. Sloan Foundation Award

2001 NSF CAREER Grant Award

**Publications:**

1\. T. Y. Koo, P. M. Gehring, G. Shirane, V. Kiryukhin, G. Lee, S-W.
Cheong, \"Anomalous transverse acoustic phonon broadening in the relaxor
ferroelectric Pb(Mg~1/3~Nb~2/3~)~0.8~O~3~\", Phys. Rev. B 65, 144113
(2002).

2\. V. Kiryukhin, Y.-J. Kim, F. C. Chou, K. J. Thomas, R. W. Erwin, Q.
Huang, M. A. Kastner, R. J. Birgeneau, \"Magnetic properties of the
S=1/2 quasi-one-dimensional magnet CaCu~2~O~3~\", Phys. Rev. B 63,
144418 (2001).

3\. P. G. Radaelli, Y. Horibe, M. J. Gutmann, H. Ishibashi, C. H. Chen,
R. M. Iberson, Y. Koyama, Y-S. Hor, V. Kiryukhin, and S-W. Cheong,
\"Formation of isomorphic Ir^3+^ and Ir^4+^ octamers and spin
dimerisation in the spinel CuIr~2~S~4~\", Nature (London) 416, 155
(2002)

4\. V. Kiryukhin, D. Casa, J.P. Hill, B. Keimer, A. Vigliante, Y.
Tomioka and Y. Tokura, \"An x-ray-induced insulator-metal transition in
a magnetoresistive manganite\", Nature (London) 386, 813 (1997).

5\. V. Kiryukhin, B. Keimer, J.P. Hill, S.M. Coad and D.M. Paul,
Synchrotron x-ray scattering study of magnetic field induced transitions
in Cu~1-x~(Zn,Ni)~x~GeO~3~\", Phys. Rev. B 54, 7269 (1996)

##### Young S. Lee

> Date of birth: September 1, 1971
>
> Massachusetts Institute of Technology
>
> Room 13-2153
>
> Cambridge, MA 02139-4307
>
> Phone: 617-253-7834
>
> Email: [younglee@](mailto:younglee@nist.gov)mit.edu

**Education**

Princeton University B.A., Department of Physics 1993

Certificate in Engineering Physics 1993

Massachusetts Institute Ph.D., Department of Physics 2000

of Technology Thesis title: "Neutron Scattering Study of

the Magnetism and Structural Phases of

Superconducting La~2~CuO~4+y~"

Advisor: Robert J. Birgeneau

### Employment

11/1999 - 8/2001 NRC Postdoctoral Research Associate,

NIST Center for Neutron Research

8/2001 - present Assistant Professor, Department of Physics,

Massachusetts Institute of Technology

### Professional Societies

American Physical Society, Neutron Scattering Society of America.

### Committees

Advanced Photon Source: Proposal Review 2002 - present

Panel (Scattering, Condensed Matter).

#### Selected Publications:

1\) K.J. Thomas, Y.S. Lee, F.C. Chou, B. Khaykovich, P.A. Lee, M.A.
Kastner, R.J. Cava, and J.W. Lynn, "*Antiferromagnetism, ferromagnetism,
and magnetic phase separation in Bi~2~Sr~2~CoO~6+δ~*," Phys. Rev. B 66,
054415 (2002).

### 

### 2) B. Khaykovich, Y.S. Lee, R.W. Erwin, S.H. Lee, S. Wakimoto, K.J. Thomas, M.A. Kastner, and R.J. Birgeneau, "*Enhancement of long-range magnetic order by magnetic field in superconducting La~2~CuO~4+y~*," Phys. Rev. B 66, 014528 (2002).

3\) S. Wakimoto, R.J. Birgeneau, M.A. Kastner, Y.S. Lee, R.W. Erwin,
P.M. Gehring, S.H. Lee, M. Fujita, K. Yamada, Y. Endoh, K. Hirota, and
G. Shirane, "*Direct observation of a one-dimensional static spin
modulation in insulating La~1.95~Sr~0.05~CuO~4~*," Phys. Rev. B **61**,
3699 (2000).

4\) R.J. Birgeneau, M. Greven, M.A. Kastner, Y.S. Lee, B.O. Wells, Y.
Endoh, K. Yamada, and G. Shirane, "*Instantaneous Spin Correlations in
La2CuO4*," Phys. Rev. B **59**, 13788 (1999).

5\) Y.S. Lee, R.J. Birgeneau, M.A. Kastner, Y. Endoh, S. Wakimoto, K.
Yamada, R.W. Erwin, S.H. Lee, and G. Shirane, "*Neutron Scattering Study
of Spin Density Wave Ordering in the Superconducting State of
Excess-Oxygen-Doped La2CuO4+y*," Phys. Rev. B. **60**, 3643 (1999).

6\) H. Kimura, K. Hirota, H. Matsushita, K. Yamada, Y. Endoh, S.H. Lee,
C.F. Majkrzak, R.W. Erwin, G. Shirane, M. Greven, Y.S. Lee, M.A.
Kastner, and R.J. Birgeneau, "*Neutron-scattering Study of Static
Antiferromagnetic Correlations in La2-xSrxCu1-yZnyO4*," Phys. Rev. B
**59**, 6517 (1999).

7\) Y.S. Lee, M. Greven, B.O. Wells, R.J. Birgeneau, and G. Shirane,
"*Spin Correlations in the Two-Dimensional Spin-5/2 Heisenberg
Antiferromagnet Rb2MnF4*," Eur. Phys. J. B **5**, 15 (1998).

8\) B.O. Wells, Y.S. Lee, M.A. Kastner, R.J. Christianson, R.J.
Birgeneau, K.Yamada, Y. Endoh, and G. Shirane, "*Incommensurate Spin
Fluctuations in High Temperature Superconductors*," Science **277**,
1067 (1997).

**Stephen Eric Nagler**

Distinguished Research Staff Member

Group Leader, Neutron Spectroscopy

Condensed Matter Sciences Division

Oak Ridge National Laboratory

Oak Ridge, Tennessee 37831

\(865\) 574-5240

# Personal Data:

Born: May 17, 1956, Calgary, Alberta

Nationality: Dual citizen of the United States and Canada

# Education:

1978 B.Sc. (Physics) University of Toronto

1982 Ph.D. (Physics) University of Toronto

# Professional Employment:

1995 - Research Staff Member, ORNL (Group Leader 1996 - )

Adjunct Professor of Physics, University of Florida (1996 - )

Adjunct Professor of Physics, University of Tennessee (1997 - )

1984 -- 1996 Professor of Physics, University of Florida, Gainesville,
FL

(Assistant Professor 1984 -- 1989, Associate Professor 1989- 1993)

1994. Visiting Scientist, Brookhaven National Laboratory

```{=html}
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```
1993. Visiting Professor, Weizmann Institute of Science, Rehovot, Israel

> 1990 -- 1991 Visiting Professor, Clarendon Laboratory, University of
> Oxford, UK
>
> 1982 -- 1984 Visiting Research Scientist, IBM Research, Yorktown
> Heights, NY

# Selected Honors and Awards:

> Fellow of the American Physical Society
>
> ORNL Scientist of the Year 1998
>
> NSF Presidential Young Investigator Award 1986-92

# Selected Professional Activities:

Current Member, SNS Experimental facilities Advisory Committee

NSERC College for review of Canada Research Chairs

> Chairman, Inelastic Scattering Subcommittee, IPNS PAC

Recent Program Committee, American Conference on Neutron Scattering,
2002

> Publication Committee, SCES 2001
>
> Member, Blume Committee on Future of Neutron Scattering

#  Selected Recent Publications:

-   B. Lake, D.A. Tennant and S.E. Nagler*, A Novel Longitudinal Mode in
    the Coupled Quantum Chain Compound KCuF~3~*, cond-mat/9910459, PRL
    **85**, 832 (2000).

-   W. Montfrooij, G.E. Granroth, D.G. Mandrus and S.E. Nagler, *Spin
    Dynamics of the Quasi-1D Ferromagnet CoCl~2~***·**

1.  *2D~2~O*, PRB **64**, 134426 (2001).

-   M.D. Lumsden, B.C. Sales, D.G. Mandrus, S.E. Nagler and J.R.
    Thompson, *Weak Ferromagnetism and Field-Induced Spin Reorientation
    in K~2~V~3~O~8~*, PRL. **86**, 159 (2001).

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```
-   B.C. Sales, M.D. Lumsden, S.E. Nagler, D. Mandrus and R. Jin,
    *Magnetic Field Enhancement of Heat Transport in the 2D Heisenberg
    Antiferromagnet K~2~V~3~O~8~*, PRL **88**, 095901 (2002).

-   S.E. Nagler, W.-T. Lee and R.M. Moon, *Design and Simulation of the
    CG1 Beamline at HFIR*, to be published in Applied Physics A
    (proceedings of ICNS 2001).

**Laurence Passell**

**Name and Date of Birth:** Laurence Passell

> March 23, 1925

**Address:** Physics Department, Building 510B, Brookhaven National
Laboratory, Upton, NY 11973-5000

> Telephone 631-344-3825
>
> e-mail passell@bnl.gov

**Education:** B.S. U.S. Merchant Marine Academy (1945)

> A.B. Harvard University (1950)
>
> M.A. University of California (Berkeley) (1952)
>
> Ph.D. University of California (Berkeley) (1955)
>
> Ph,D. thesis - Thermal Conductivity of Aluminum Below One Degree
> Absolute; thesis advisor - Professor H.B. Silsbee

**Employment:** (1945-46) Assistant Port Engineer, U.S. War Shipping
Administration

> \(1951\) Los Alamos National Laboratory
>
> (1955-61) Lawrence Livermore Radiation Laboratory
>
> (1961-63) Risoe National Laboratory
>
> (1963-95) Brookhaven National Laboratory
>
> (1995-present) Brookhaven National Laboratory (consultant)

**Professional Societies:** American Physical Society (Fellow)

> Sigma Xi

**Committees:** SNS Neutron Optics Committee

**Awards and Honors:** Department of Energy 1998 Materials Science Award
for Sustained Research in Materials Chemistry

**Publications:**

The Performance of Reflecting Multi-Channel Collimators as Neutron Beam
Filters and Polarizers; H.B. Moller, L. Passell and F.
Stecher-Rasmussen - J. Nucl. En. 17, 227 (1963)

Nuclear Polarization in EuS and EuO; L. Passell, V.L. Sailor and R.I.
Schermer - Phys. Rev. 135A, 1767 (1964)

Measurement of the Spin Dependence of the 3He(n,p)T Reaction and of the
Susceptibility of Adsorbed 3He; L. Passell and R.I. Schermer - Phys.
Rev. 150, 146 (1966)

Excitations in Few-Atomic-Layer Adsorbed Helium Films: The
Two-Dimensional Roton; W. Thomlinson, J.A. Tarvin and L. Passell - Phys.
Rev. Lett. 44, 266 (1980)

Composite Germanium Monochromators for High Resolution Neutron Powder
Diffraction Applications; J.D. Axe, S. Bar-Ziv, S. Cheung, D.E. Cox, L.
Passell and T. Vogt - J. Neutron Res. 2, 85 (1994)

# REGNAULT Louis-Pierre

**Date of Birth:** February 4 1952

**Address:** CEA-Grenoble, 17 Rue des Martyrs 38054 Grenoble cedex 9,
France

> Tel: +33438783137 Fax: +33438783137 e-mail: regnault@ill.fr

**Education:** o \"Physics Master\", University of Grenoble, 1974

> o \"D.E.A.\" in Solid State Physics, University of Grenoble, 1975.
>
> o \"3rd Cycle\" thesis, University of Grenoble, 1976 (Title: \"Ordre
> magnetique dans le compose a structure bidimensionnelle BaCo2As2O8\";
> Supervisor: J. Rossat-Mignod).
>
> o Ph.D. Thesis, University of Grenoble, 1981 (Title: \"Contribution a
> l\'etude des excitations non-lineaires dans des systemes uni et
> bidimensionnels a anisotropie planaire\"; Supervisor: J.
> Rossat-Mignod).
>
> o Habilitation, 1985

**Employement:** 1976-1981 PhD at CEA-CENG-DRF, Neutron scattering
laboratory (DRF/DN).

> 1981 "Ingénieur\" CEA . Responsible for the three-axes spectrometer

(TAS) DN1 at the Siloé reactor, CEN-Grenoble.

> 1991-1995  Adjoin director of the MDN laboratory at CEN-Grenoble.
>
> Since 1995 Director of the MDN laboratory. Head of the CEA-\"CRG\"
> group
>
> at the ILL (D15, D23, IN12 and IN22).
>
> 1995-1998 Leader of the \"H25\" Project (construction of a polarised
> neutron
>
> diffractometer (D23) and a polarised three-axis spectrometer with a
> longitudinal and a spherical polarisation analysis option

(IN22) on a supermiror guide).

> 1995-2002 First responsible of the \"CRG\" TAS IN22 at ILL.

**Professional societies:** Member of the French and European Physical
Societies (SFP and EPS).

> Member of the French and Swiss Neutron Societies (SFN and SNS!).

**Committees and \"networks\":**

> Since 1999: Member of the ILL \"working-group\" on neutron
> polarimetry.
>
> Since 2000 : Member of the ILL \"Instrumentation subcommittee\".
>
> From 1996 to 2000: Member of the X-ENNI European network on neutron
> polarisation (Large area Heusler-based polarisers and
> polarisation-analysis devices for TAS; Spherical polarimetry for INS;
> Polarised neutron scattering under high magnetic fields).
>
> Since 2000: Member of the ENPI (European Neutron polarisation
> Initiative) network (Construction of a third-generation \"CRYOPAD\"
> optimised for inelastic neutron scattering; Spherical polarimetry on
> TAS).

**Awards and Honors:** None. But my successive bosses got them for me!

> Since 2002 : \"Directeur de Recherche\" at CEA.

**Publications concerning polarised neutrons:**

\"Polarized neutron scattering on low-dimensional systems\", L.P.
Regnault, Proceedings of the \"French-Japanese Symposium in Fukuoka, ed.
Y. Ajiro and J.P. Boucher, (Kyushu University Press, 2002) 93-101.

\"Chiral criticality in helimagnet Ho studied by polarized neutron
scattering\", V.P. Plakhty, W. Schweika, Th. Bruckel, J. Kulda, S.V.
Gavrilov, L.P. Regnault, and D. Visser, Phys. Rev. B 64 (2001)
100402-405.

\"Magnetization distribution in Si-doped spin-Peierls compound CuGeO3\",
B. Grenier, E. Ressouche, L.P. Regnault, J.E. Lorenzo, E.
Lelievre-Berna, G. Dhalenne, and A. Revcolevschi. Physica B **297**
(2001) 221-225.

\"Application des neutrons polarisés a l\'etude des excitations
magnétiques\", L.P. Regnault,

J. Phys. IV France **11** (2001) 253-269.

\"Antiferromagnetic ordering in superconducting YBa2Cu3O6.5\", Y. Sidis,
C. Ulrich, P. Bourges, C. Bernhard, C. Niedermayer, L.P. Regnault, N.H.
Andersen, and B. Keimer, Phys. Rev. Lett. **18** (2001) 4100-4103.

\"Coupled magnetic and structural transitions in EuMn2O5 as studied by
neutron diffraction and three-dimensional polarization analysis\", V.
Polyakov, V. Plakhty, M. Bonnet, P. Burlet, L.P. Regnault, S. Gavrilov,
I. Zobkalo, and O. Smirnov, Physica B 297 (2001) 208-212.

\"The current status of the 3He neutron spin filter (NSF) project at the
ILL\", T.W. Roberts, H. Humblot, F. Tasset, E. Lelièvre-Berna, A.R.
Wildes, A. Ivanov, A. Petoukhov, L.P. Regnault, A.D. Hiller, J. Kulda,
J.R. Stewart, M. Thomas, P. Malbert, D. Jullien, Y. Gibert, P. Gay, E.
Bourgeat-Lami, and R. Chung, Physica B **297** (2001) 282-287.

\"Cryopol: a superconducting magnetostatic cavity for a 3He neutron spin
filter\", J. Dreyer, L.P. Regnault, E. Bougeat-Lami, E. Lelièvre-Berna,
S. Pujol, F. Thomas, M. Thomas, F. Tasset, Nuclear Instrumentation and
Methods A **449** (2000) 638-648.

\"Incommensurate antiferromagnetic fluctuations in superconducting
YBa2Cu3O6.85\", H.M. Ronnow, L.P. Regnault, C. Ulrich, B. Keimer, P.
Bourges, and Y. Sidis, ILL Annual Report 2000
(http://www.ill.fr/AR-00/scientific.htm).

\"Polarized neutron inelastic scattering on the spin-Peierls system
CuGeO3: \"three-directional\" versus \"three-dimensional\" polarisation
analysis\", L.P. Regnault, F. Tasset, J.E. Lorenzo, T. Roberts, G.
Dhalenne, and A. Revcolevschi, Physica B **267-268** (1999) 227-235.

James J. Rhyne

**Name and Date of Birth:** James J. Rhyne

> 11/14/1938

**Address:** Physics Dept., Univ. of Missouri, Columbia, MO 65211

> \(573\) 882-6506. email: <rhynej@missouri.edu>

**Education:** • Ph.D. in Physics, Iowa State University, 1965, Thesis
Title: *Magnetostriction in Rare Earth Metals,* S. Legvold, thesis
supervisor

• M.S. in Physics, University of Illinois, 1961

• B.S. in Physics (with honors), University of Oklahoma, 1959

**Employment (partial list):** • Research Physicist, Solid State
Division, Naval Ordnance Laboratory (NOL), 1965‑1975.

> • Research Physicist, Reactor Radiation Division, National Institute
> of Standards and Technology (NIST), 1975‑1990
>
> • Visiting Scientist, Riso National Laboratory, Roeskilde, Denmark,
> 1978.
>
> • Director, NSF/NIST Center for High Resolution Neutron Scattering,
> National Institute of Standards and Technology (formerly the National
> Bureau of Standards), 1988‑1990.
>
> • Director, University of Missouri Research Reactor Center, 1991 --
> 1996
>
> • Professor, Department of Physics, University of Missouri‑Columbia,
> 1991 ‑ present.

• Faculty Appointment, Reactor Radiation Division, NIST, January
1991‑September 1995; Guest Worker, October 1995-present.

**Professional Societies:**

> • Fellow, American Physical Society and Washington Academy of Sciences

**Committees (partial list):** • President, Neutron Scattering Society
of America, elected 1999 (3 year term)

> • Member, Executive Committee, GMAG, American Physical Society,
> elected 1999 (3 year term)
>
> • Member, Basic Energy Sciences Advisory Committee, Subpanel on
> Neutron Sources, 2000.
>
> • Advisory Editor, Journal of Magnetism and Magnetic Materials,
> 1990‑present.
>
> • Chair, Neutron Instrumentation Panel, DOE Facilities Initiative
> Review, Chantilly, VA, May 1-2, 1996.
>
> • Member, Intl. Atomic Energy Agency (IAEA) Advisory Group on *Use of
> Research Reactors for Solid State Studies*, Vienna, Austria, March
> 29-April 1, 1993.

• Member, Scientific Committee, Louis Néel Laboratory, C.N.R.S.,
Grenoble, France, 1989‑1991.

• Delegate to the Megascience Forum on Neutron Sources sponsored by the
International Organization for Economic Cooperation and Development,
Knoxville, November 1994.

• Member, National Steering Committee, Advanced Neutron Source Project,
1992-1995.

> • Member, Advisory Committee, Los Alamos Neutron Scattering Center,
> 1991 ‑ 1994.
>
> • Chairman, Program Review Committee, Argonne and Los Alamos National
> Laboratories Pulse Neutron Sources, 1989; Member 1986‑1989.
>
> • Member, Editorial Board, Journal of Applied Physics, 1986‑1989.
>
> • Publications Chairman and Member Executive Committee, l985
> International Conference on Magnetism, l98l‑1985.

**Awards and Honors:** • Doctor Honoris Causa, University Henri
PoincarJ, Nancy, France, conferred June 20, 1995

> • Fellow, American Physical Society and Washington Academy of Sciences
>
> • Department of Commerce Gold Medal Award, 1987; Silver Medal Award,
> 1984
>
> • National Bureau of Standards Bronze Medal Award, 1981

**Publications (partial list):**

> • "Spin Dynamics And Absence Of A Central Peak Anomaly In
> La~0.67~Ca~0.33~MnO~3~ ," J.J. Rhyne, H. Kaiser, L. Stumpe, J.F.
> Mitchell, T. McCloskey, and A.R. Chourasia, J. Appl. Phys. **87**,
> 5813 (2000).
>
> • "Composition dependence of the spin wave stiffness parameter in
> La~1-x~Ca~x~MnO~3~ CMR materials," J.J. Rhyne, H. Kaiser, L. Stumpe,
> J.F. Mitchell, T. McCloskey, and A.R. Chourasia, J. Mag. And Mag.
> Matls. **226-230,** 775 (2001).
>
> • "Spin Excitations in \[La~1-x~Ca~x~MnO~3~\] in the Mixed-Phase
> Region," L. Stumpe, B. Kirby, H. Kaiser, J.J. Rhyne, and J.F.
> Mitchell, J. Appl. Phys. **91,** 7511 (2002).
>
> • "Long Wavelength Spin Dynamics in La~0.53~Ca~0.47~MnO~3~," J.J.
> Rhyne, H. Kaiser, H. Lao, Gang Xiao, and M.L. Gardel, J. Appl. Phys.
> **83**, 7339 (1998).
>
> • "Concurrent Nd and Mn Spin Excitations in Nd~0.6~Sr~0.4~MnO~3~," H.
> Kaiser, L.E. Stumpe, J .J. Rhyne, Y. Tokura, and H. Kuwahara," J.
> Appl. Phys. J. Appl. Phys. **85**, 5564 (1999).
>
> • "Small Angle Neutron Scattering of Nanodispersed Magnetic
> Particles," J.R. Childress, C.L. Chien, J.J. Rhyne, and R.W. Erwin,
> *J. Mag. and Mag. Matls.* **104-107**, 1585 (1992).
>
> • "Neutron Scattering Study of the Magnetic Correlations of Iron‑Rich
> Fe‑Ni‑Zr Glasses," J.A. Fernandez‑Baca, J.J. Rhyne, R.W. Erwin and
> G.E. Fish, *J. de Physique, Colloque C8, Suppl. #12,* **49**, 1207
> (1988).
>
> • "Magnetism in Artificial Metallic Superlattices of Rare Earth
> Metals," J. J. Rhyne and R. W. Erwin, Chapt. 1, *Handbook of*
> *Magnetic Materials* *, Vol. 8*, edited by K.H.J. Buschow, North
> Holland Science Publishers, pp. 1-56 (1995).
>
> • "Spin Dynamics of Amorphous Magnets," J.W. Lynn and J.J. Rhyne,
> Chapter 14, *Spin Waves and Magnetic Excitations, Vol. 2,* edited by
> S.K. Sinha and A.S. Borovik‑Romanov, North Holland Physics Publishers,
> Amsterdam, 1988, pp. 177‑217.

Constantine J. Stassis

Physics Department, Iowa State University

Ames, Iowa 50011

Tel (515)-292-4224

Fax (515)-294-0689

e-mail [stassis@ameslab.gov]{.underline}

**Education:** B.S. Physics, 1960, École Polytechnique de l' Université
de Lausane,

> Switzerland
>
> M.S. Physics, 1961, École Polytechnique de l' Université de Lausane,
>
> Switzerland
>
> Ph.D. Physics, 1970, Massachusetts Institute of Technology (MIT), USA

thesis: "Polarized Neutron Study of Nagaoka's Quasibound State"

thesis supervisor: Prof. C. G. Shull (deceased)

**Employment:** 1970: Post-doctoral Research Associate, MIT

> 1971: Instructor, Iowa State University and Assistant Physicist Ames
> Laboratory
>
> 1972: Assistant Professor, Iowa State University and Associate
> Physicist Ames Laboratory
>
> 1975: Associate Professor, Iowa State University and Physicist Ames
> Laboratory
>
> 1979-present: Professor of Physics, Iowa State University and Senior
> Physicist Ames Laboratory
>
> 1987: Visiting Scientist, Brookhaven National Laboratory
>
> 1989: Visiting Scientist, Brookhaven National Laboratory
>
> 1987-1988: Visiting Professor of Physics, University of Crete, Greece
>
> 1996: Summer Visiting Scientist, Brookhaven National Laboratory

**Professional Societies:** Member, American Physical Society; Fellow,
American Physical Society; Member, Neutron Scattering Society of America
(NSSA); Member, Executive Committee and Membership Secretary of the
Neutron Scattering Society of America (NSSA)(1993-present); Member,
Joint Spallation Neutron Source (SNS) and High Flux Isotope Reactor
(HFIR) Users Committee (SHUC)(1998-present).

**Awards and Honors:** 1997 Co-recipient of the DOE Annual Award for
Outstanding Accomplishments in Solid State Physics.

**Publications:**

J. Zarestky, C. Stassis, A. Goldman, P. Canfield, G. Shirane, S.M.
Shapiro, "Phonon-Phonon Interactions in (Lu,Y)Ni2B2C,"
*J.Phys.Chem.Sol.,* **63**, 811 (2002*)*.

Ll. Mañosa, Antonio Planes, J. Zarestky, T. Lograsso, D.L. Schlagel, C.
Stassis, "Phonon Softening in Ni‑Mn-Ga alloys" *Phys. Rev. B*, **64**,
p. 024305 (2001).

C. Stassis, "Neutron Scattering," Chapter 17 in *Handbook of Elastic
Properties of Solids, Liquids and Gases,* Academic Press (New York, NY)
(2001).

I.R. Fisher, Z. Islam, J. Zarestky, C. Stassis, M.J. Kramer, A.I.
Goldman and P.C. Canfield, " Magnetic Properties of Icosahedral R-Mg-Zn
quasicrystal (R=Y, Tb, Dy, Ho and Er) *J. Alloys Compd*. **303-304**,
223 (2000).

C. Stassis, "Techniques for the Study of Phonons," Section 14.7 in
*Methods of Materials Research*, John Wiley and Sons, Inc. (2000).

S. H. Lee, C. F. Majkwzak, S. K. Sinha, C. Stassis, H. Kawano, G.
Lander, P. Brown, H. F. Fong,\
S. W. Cheong, H. Matsushita, K. Yamada, Y. Endoh, "Search for Orbital
Moments in Underdoped Cuprate Metals -- A Sisyphian Experience," *Phys.
Rev. B* **60**, 10405 (1999)**.**

J. Zarestky, C. Stassis, A. Goldman, P. Canfield, G. Shirane, S.
Shapiro, "Phonon Profiles in Superconducting YNi2B2C and LuNi2B2C,"
*Phys. Rev. B* **60**, 11932 (1999).

C. Stassis, J. Zarestky, A. Goldman, P. Canfield, G. Shirane, S.
Shapiro, "Anomalous Phonons Below Tc in Superconducting RNi2B2C (R = Lu,
Y)," *Physica C* **317-318**, 127 (1999).

> **Andrey  Zheludev**

## Curriculum Vitae

**Place and date of birth:** Moscow, Russia, October 17, 1969

> .

**Address** Oak Ridge National Laboratory

> Building 7962, MS 6393
>
> P.O. Box 2008
>
> Oak Ridge, Tennessee 37831-6393

**Education**

1994 **Ph.D.** in Physics,  *summa cum laude*, Université  Joseph
Fourier, Grenoble, France. [Title]{.underline}: \"Etudes de cristaux
magnetique moleculaires par diffraction de neutrons.\"
[Supervisor]{.underline}: Dr. J. Schweizer, CEA Grenoble.

1991 **M.S.** in Physics, *summa cum laude*, Moscow Institute for
Physics and Technology (MIPT) and the P.L.Kapitza Institute for Physical
Problems,  Russian Acad. Sci.  (IPP), Moscow, Russia

1991 **M.S.** in Applied Mathematics, *summa cum laude*, MIPT and IPP

1989 **B. S.** in Physics, Faculty of General and Applied Physics, MIPT,
Moscow, Russia

1989. **B.S.** in Mathematics, MIPT, Moscow, Russia

**Employment**

2001-Present Research Staff II, Solid State Division, Oak Ridge National
Laboratory

2000-2001 Physicist, Physics Department, Brookhaven National Laboratory

1998-2000 Associate Physicist, Physics Department, BNL

1996-1998 Assistant Physicist, Physics Department, BNL

1994-1996 Research Associate, Physics Department, BNL

1994. Junior Research Associate, Centre d\'Etudes

Nucleaires de Grenoble, France

1993. Junior Research Associate, P.L.Kapitza Institute for

Physical Problems, Russian Acad. Sci., Moscow,

Russia

**Membership in professional associations**

1994-1999, 2002-present American Physical Society

1996-present Neutron Scattering Society of America

**Honors and awards**

2000 2000 The Presidential Early Career Award For Scientists and
Engineers.

> 2000 US DOE Office of Science Early Career Scientist and Engineer
> Award.

1997 INS approval of permanent US residency petition filed by Brookhaven
National Laboratory under the category \`\`Outstanding ability\'\'.

1993 CEA (France) award for \`\`Prominent Research Achievements in
Condensed Matter Physics\'\' for work on New Orgainc Magnetic Materials.

1991. Fellowship for Outstanding College Students, MIPT.

>  

**10 selected recent publications in neutron scattering**

 

[A. Zheludev,]{.underline} K. Kakurai, T. Masuda, K. Uchinokura, K.
Nakajima, *Dominance of excitation continuum in the longitudinal
spectrum of weakly coupled Heisenberg S=1/2 chains*, Phys. Rev. Lett.
**89**, 197205 (2002).

 

[A. Zheludev]{.underline}, Z. Honda, Y. Chen, C. L. Broholm, K.
Katsumata, S. M. Shapiro, *Gapless excitations in the high-field phase
of a Haldane antiferromagnet*, Phys. Rev. Lett **88**, 077206 (2002).

 

[A. Zheludev]{.underline}, E. Ressouche, I Tsukada, T. Masuda and K.
Uchinokura, Structure of the multiple spin-flop states in BaCu2Si2O7,
Phys. Rev. B **65**, 174416 (2002);

 

[A. Zheludev]{.underline}, M. Kenzelmann, S. Raymond, T. Masuda, K.
Uchinokura, S.-H. Lee, Spin dynamics in the S=1/2 weakly-coupled chains
antiferromagnet BaCu2Si2O7, Phys. Rev. B **65**, 014402 (2001).

 

[A. Zheludev]{.underline}, S. Maslov, T. Yokoo, J. Akimitsu, S. Raymond,
S. E. Nagler, Quantum and classical dynamics in complex one-dimensional
antiferromagnets, J. Phys.: Condens. Matter **1**, R525-R536 (2001).

 

Y. Chen, Z. Honda, [A. Zheludev]{.underline}, C. Broholm, K. Katsumata
and S. M. Shapiro*, Field-induced 3- and 2-dimensional freezing in a
quantum spin liquid*, Phys. Rev. Lett**. 86**, 1618 (2001).

 

[A. Zheludev]{.underline}, Z. Honda, K. Katsumata , R. Feyerherm and K.
Prokes, Field-induced commensurate long-range order in the Haldane-gap
system Ni(C5 H14 N2 )2 N3 (ClO4 ), Europhys. Lett. **55**, 868 (2001)

 

[A. Zheludev]{.underline}, M. Kenzelmann, S. Raymond, E. Ressouche, T.
Masuda, K. Kakurai, S. Maslov, I. Tsukada, K. Uchinokura, A. Wildes,
*Energy separation of single-particle and continuum states in a S=1/2
weakly-coupled chain antiferromagnet*, Phys. Rev. Lett., **85**, 4799
(2000).

 

Y. Uchiyama, Y. Sasago, I. Tsukada, K. Uchinokura, [A.
Zheludev]{.underline}, T. Hayashi, N. Miura and P. Boni,
*Spin-Vacancy-Induced Long-Range Order in a New Haldane-Gap
Antiferromagnet*, Phys. Rev. Lett**.**, **83**, 632 (1999).

  

[A. Zheludev]{.underline}, S. Maslov, G. Shirane, I. Tsukada, T. Masuda,
K. Uchinokura, I. Zaliznyak, R. Erwin, L. P. Regnault, *Magnetic
anisotropy and low-energy spin waves in the Dzyaloshinskii-Moriya spiral
magnet Ba2CuGe2O7*, Phys. Rev. B **59**, 11432 (1999).

 

![](media/image9.png){width="5.981944444444444in"
height="8.997916666666667in"}

**Appendix C. HYSPEC Top Level Specifications.**

This document defines "top-level" requirements for all components of the
hybrid spectrometer, HYSPEC, planned for installation on beamline 15
(BL15) of the Spallation Neutron Source (SNS) that is now under
construction at Oak Ridge National Laboratory. All HYSPEC components,
whether designed by the Instrument Development Team (IDT), members of
the SNS staff, or by third party manufacturers, are expected to comply
with these requirements. It becomes effective only if signed by all of
the parties whose names appear below. Changes and additions (or
deletions) can be initiated by any of the signatories (or their
replacements) at which time a revised document must be prepared with all
modified sections identified as such. They become effective only after
all parties sign the revised document. Whenever revisions are made, the
earlier document is to be retained as part of the IDT record.

Principal Investigator: S. Shapiro ................................,
Date .........\...

Principal Investigator: I. Zaliznyak ................................,
Date .........\...

Project Scientist: TBA ................................, Date
.........\...

SNS Instrument Systems: K. Crawford ................................,
Date .........\...

SNS EFD Head: I. Anderson ................................, Date
.........\...

SNS Director: T. Mason ................................, Date
.........\...

Requirements for HYSPEC.^(1)^

1.  **Instrument footprint and placement on the floor.**

> HYSPEC shall be placed at the end position of the SNS beam-line
> illuminated by a coupled, supercritical H~2~ moderator. Sufficient
> floor space must be available at this position to accommodate the
> instrument's secondary spectrometer for all incident energies and
> sample scattering angles specified in sections 3 and 5 below. The
> greater part of the instrument footprint will be a 6.3 m radius
> semi-circle, on one side of the beam-line or the other. It will be
> centered at the monochromator position, at a distance L~SM~ of about
> 20 to 25 m from the moderator face; nominal moderator-to-monochromator
> distance L~SM~ = 20000 mm is used in this document. It is assumed that
> this semi-circular footprint shall be entirely inside the SNS
> experimental hall. A combined "get-lost" pipe and beam-stop -- if they
> prove to be necessary -- may extend outside the building.
>
> It is currently envisioned that HYSPEC will be located on BL15, behind
> a shorter instrument served by an ambient water moderator on BL16A.
> Should SNS Instrument Team judge that spectrometer footprint cannot be
> accommodated on BL15 in accordance with the above requirements a
> mutually acceptable alternative shall be negotiated between the HYSPEC
> IDT and the SNS. The possible alternatives, in the IDT order of
> preference, are: (i) HYSPEC reassignment to another beam-line served
> by a coupled, super-critical H~2~ moderator, such as BL14B; (ii)
> slight modification of the instrument design by reducing the secondary
> flight-path: the energy resolution is relaxed proportionally, but the
> footprint is reduced also; this, however, may also impact the
> polarization sensitivity; (iii) complete re-design of the instrument
> secondary spectrometer so that the longest secondary flight-path
> available for each scattering angle is used, as a result the footprint
> becomes elongated and "pear-shaped"; (iv) extending the spectrometer
> primary flight-path to a building outside the SNS experimental hall;
> at a given analyzer resolution this reduces the incident neutron flux
> in proportion to the length of the primary spectrometer, and, while
> being more expensive, is somewhat equivalent to reducing the secondary
> flight-path.

2.  **Primary flight-path system**

    1.  **Neutron guide system**

> The incident neutron guide system is to be composed of three
> super-mirror guide sections, **G1-G3,** all with top and bottom
> coatings with critical angles of 3θ^Ni^~c~ and with side coatings with
> the largest practical critical angle larger than 3θ^Ni^~c~. **G1** is
> to be integrated into the primary shutter. So located, its upstream
> end with an internal aperture of *w~0~* x *h~0~* = 40 mm x 128 mm will
> be at a distance L~0~ = 2000 mm from the front face of the coupled,
> supercritical H~2~ moderator. Gaps of the smallest possible size are
> to be provided in the guide system to accommodate shutter, choppers
> and (if necessary) a beam filter assembly. **G2** and **G3**, the
> sections external to the biological shield, are to be steel-jacketed.
> All guide sections shall be 40 mm wide; their internal vertical
> profiles will be chosen to optimize the neutron current illuminating
> the 240 mm tall, vertically-focusing monochromator crystal that will
> be located downstream of **G3** at a distance of L~SM~ = 20000 mm from
> the front face of the moderator. Optimization is to be achieved at a
> reference incident neutron energy E~i~ = 15 meV. Existing Monte-Carlo
> simulations indicate that the optimum guide dimensions are:

  --------------- --------------- ------------------- -------------------
  Guide section   Length          Entrance size, *w*  Exit size, *w* x
                                  x *h*               *h*

  **G1**          5000 mm         40 mm x 128 mm      40 mm x 150 mm

  **G2**          11000 mm        40 mm x 150 mm      40 mm x 150 mm

  **G3**          2000 mm         40 mm x 150 mm      40 mm x 180 mm
  --------------- --------------- ------------------- -------------------

> These dimensions will be further refined as design work proceeds,
> however, and might, at a later stage, differ slightly from the above
> values.
>
> The guide support system should be designed to allow easy alignment of
> the individual guide segments (both vertically and laterally) with
> positional precision better than 0.5 mm and angular precision better
> than 1 minute of arc.
>
> To the extent feasible, the primary flight path sections should be
> either evacuated or filled with ^4^He gas to minimize air scattering
> losses.

2.  **Beam line shielding**

> Beam line shielding shall consist of a stationary bottom piece
> carrying the guide support and alignment systems and removable modular
> pieces on the sides and top. The removable shielding is to be designed
> so as to: (i) minimize the space immediately surrounding the guide
> system (as specified in section 2.1) that is not filled with shielding
> material; (ii) minimize the total thickness and weight of the modular
> shielding and (iii) provide rapid and convenient access to the
> choppers and (if installed) filters for maintenance and, if necessary,
> for their removal. Shielding shall be composite and contain materials
> needed both to slow down and absorb neutrons and to absorb the prompt
> gamma radiation. Radiation dose rates and background outside the beam
> line shielding shall be as low as reasonably achievable (ALARA); less
> than 5 mR/hr and in compliance with the limits established by the SNS.

3.  **Shutter**

> The primary beam shutter for the instrument shall be the SNS shutter
> inside the biological shield. When closed it must reduce the radiation
> incident on the choppers and monochromator crystal sufficiently to
> allow them to be removed for repairs while the SNS is operating at
> full power and also reduce the radiation level at the sample position
> to less than 5 mR/hr. The **G1** section of guide is to be built into
> the "open" channel of the shutter, as specified in section 2.1.
> Shutter position shall be controlled by a single switch interlocked to
> form a radiation exclusion zone details of which are to be specified
> by SNS. A clearly visible sign will show the shutter position; this
> information shall also be available to the instrument control
> computer. Shutter opening and closing times are to be less than 30
> sec.

4.  **Filters**

> If MCNP-X based neutronics calculations indicate that single crystal
> beam filters can significantly reduce fast neutron beam contamination,
> a three-position filter exchanger is to be positioned immediately
> downstream of the in-shield shutter. The filters are to be large
> enough in their lateral dimensions to intercept the full beam as
> specified in section 2.1. Each filter shall have the same supermirror
> coatings and shielding as the **G1** guide so that neutrons must
> either pass through the filter or be absorbed in the surrounding
> shielding. A refrigerator system should be provided to cool the
> filters to 77 K (or colder) and maintain them at that temperature even
> when fully illuminated by the neutron beam. Filter transmission better
> that 60% for neutrons throughout the energy range 5\<E~i~\<90 meV is
> defined as being acceptable. Filter changes are to be effectuated from
> the instrument control computer. The filter choices shall be:

1.  **None:** An open channel with lateral dimensions that accommodate
    the full beam as specified in 2.1.

2.  **Sapphire:** Single crystal sapphire grade B4 or better with a beam
    path length of 100 mm (available from Crystal Systems Inc.). The
    orientation of the single crystal material is to be uniform
    throughout the filter to within 10 degrees. However, the average
    crystal orientation with respect to the beam direction is
    unimportant and should be chosen to minimize cost.

3.  **PG:** Pyrolytic graphite grade ZYH with a total beam path length
    of 100 mm (available from Advanced Ceramics). The c-axes of the
    individual crystal plates must be aligned to within 2 degrees of the
    local beam axis.

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3.  **Monochromating system**

    1.  **General principle**

> Incident neutron energy selection in HYSPEC shall be defined by the
> combined effects of time-of-flight (TOF) along the primary flight-path
> and Bragg reflection from the monochromator crystal. TOF energy
> selection relies on restricting the burst time τ~0~; i.e. the time
> interval during which the sample is illuminated by the incident
> neutron beam. A counter-rotating disc chopper pair, **T~2~,**
> positioned as close as possible to the upstream face of the
> monochromator crystal is to be used to define burst times τ~0~ \> 50
> μs. An additional "rotating collimator"-type Fermi- chopper, **T~3~,**
> operating at high rotation speeds shall be used in those cases where
> shorter burst times are needed. It is to be placed at the downstream
> end of the converging supermirror guide **G4** between the
> monochromator crystal and the sample, as described in section 3.5.
>
> Crystal monochromator with variable vertical curvature shall serve to
> vertically focus the 240 mm tall neutron beam delivered by the guide
> system onto a sample placed in the beam center at a distance L~MS~
> from the monochromator rotation axis. The crystals will also serve as
> pulse-shapers, cutting off much of the unwanted higher-energy tail
> from the spectral distribution of neutrons produced by the moderator.
> Pyrolytic graphite crystals will be used for most unpolarized beam
> applications although in certain cases where very low incident neutron
> energies are needed fluorinated synthetic mica crystals may be
> employed. For polarized beam studies, a vertically-focusing Heusler
> alloy crystal monochromator will be used to provide polarized
> monochromatic neutrons incident on the sample. The monochromator
> crystals shall be mounted in fixtures such that they can be remotely
> aligned and also remotely rotated around a vertical axis to define the
> "take-off" angles needed to Bragg reflect neutrons with energies in
> the nominal range 2.5\<E~i~\<100 meV.
>
> A sample position arm rotating around the monochromating crystal shall
> connect the monochromator axis and the sample stage with its alignment
> and rotation axes. The arm shall hold a converging super-mirror guide,
> a Fermi chopper, a collimator, an incident beam monitor, beam defining
> slits, beam attenuators (including a beam shutter), and a polarized
> beam equipment such as a guide field and flipper for polarized
> applications. It shall be rigidly attached to the rotating exit
> aperture in the monochromator crystal shielding in such a way that the
> sample is always at the center of the monochromatic neutron beam
> reflected by the crystal. The converging super-mirror guide,
> Fermi-chopper and collimator are all to be contained within the
> monochromator shielding. Distances from the monochromator to the
> sample, L~MS~, and to the upstream counter-rotating chopper pair,
> L~T1M~, should be minimized while maintaining all other
> specifications. In normal operation the nominal value for L~MS~ is
> assumed to be 1800 mm.

2.  **Disk choppers**

> Three disk choppers designated **T~0~**, **T~1~** and
> **T~2\ ~**rotating about their horizontal axes at a multiple or
> sub-multiple of the source frequency and kept very precisely in phase
> with the source shall be installed in the primary flight-path. All
> should fit as tightly within the gaps between guide sections as
> possible, housed in SNS approved, blast-proof housings, and should
> have neutron-transparent windows which, as the chopper rotate, provide
> time-dependent and uniform vertical illumination of the full
> downstream guide apertures as specified in section 2.1. Beam
> transmission should be at least 98% in the chopper "open" positions
> for neutrons with energies in the range 2.5\<E~i~\<100 meV; a minimum
> beam attenuation of 10^-5^ in the chopper "closed" position is defined
> as being acceptable. To the extent feasible, chopper modules shall be
> based on the standard designs developed by the SNS Instrument Systems
> Group. Because choppers are significant sources of scattering,
> additional modular shielding is to be placed around the beam-line at
> each chopper position to reduce radiation leakage to acceptable levels
> as specified in section 2.2.

1.  **T~0~ chopper:** A chopper with a highest rotation rate of 120 Hz
    and a lowest rotation rate 30 Hz made of a material that efficiently
    blocks fast neutrons and gamma-rays from the moderator is to be
    placed as close as possible to the moderator shielding face or
    possibly inside it. This chopper must block prompt fast neutrons and
    gamma rays but be open to neutrons in the energy range
    2.5\<E~i~\<100 meV. Also its "open" channel should be
    supermirror-coated and of the same lateral dimensions specified in
    section 2.1 for the surrounding guide so that the downstream guide
    is fully illuminated when the chopper is open.

2.  **T~1~, the order**-**suppressing and frame-overlap chopper:** This
    chopper is to be a 300 mm radius, single rotor disc chopper with a
    highest rotation rate of 240 Hz and a lowest rate of 30 Hz. It shall
    be located either between guide sections **G1** and **G2**, or in a
    gap in **G2**. The chopper should be designed to remove all unwanted
    higher-order neutrons that could otherwise pass through the **T~2~**
    chopper (when operating at high rotation speeds) and be reflected by
    the monochromator crystal. In cases where frame overlap
    contamination becomes a problem either this chopper or the **T~0~**
    chopper (or both) should be capable of being operated at half the
    source frequency (30 Hz) to block alternate pulses from the
    moderator.

3.  **T~2~, the energy-defining chopper:** This is a double-rotor
    chopper composed of a pair of the counter-rotating 300 mm radius
    disk choppers with a highest operational rotation rate of 360 Hz. It
    should be placed as close as practical to the front face of the
    monochromator crystal, either between guide sections **G2** and
    **G3** or in a gap in guide **G3**.

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3.  **Monochromator crystal assemblies**

> HYSPEC shall have two or more vertically focusing, segmented crystal
> monochromators mounted on a remotely-controlled exchanger; one shall
> be of pyrolytic graphite (PG) and one of Heusler alloy. Optional
> additional monochromator crystals based on intercalated PG, synthetic
> mica, silicon or germanium will be specified at a later stage. Their
> design is to be based on standard GMI-type segmented frames with a
> single-motor-driven mechanism to vary vertical curvature. Individual
> crystal segments shall be attached to aluminum alloy plates of the
> minimum practical thickness using aluminum screws or pins. All
> monochromator crystal assemblies should be of dimensions *w~m~* x
> *h~m~* = 240 mm x 240 mm so as to accommodate the full size of the
> neutron beam exiting guide **G3** for all scattering angles 20º \<
> 2θ~m~ \< 120º. All parts of the monochromator frame and its support
> and crystal exchange mechanisms and such other components as a
> magnetic yoke to provide the field needed to saturate the Heusler
> crystals are to be covered with a neutron-absorbing material such as
> B~4~C and/or LiF. It should be possible to remove either or both
> monochromating crystal assemblies from the instrument for service
> while the SNS is in full power operation. A web camera with
> appropriate lighting shall be provided to enable remote viewing of the
> monochromators for diagnostic purposes when they are moved.

1.  **PG monochromator:** shall be assembled of 3x60 = 180 individual
    rectangular plates of ZYA grade pyrolytic graphite (from Advanced
    Ceramics or another vendor) with an isotropic intrinsic (x-ray)
    mosaic spread with a full width at half maximum (FWHM) of 25(5)
    minutes of arc. The plates shall be 1 mm thick and have lateral
    dimensions *w* x *h* = 80 mm x 12 mm. The plates shall be attached
    to the holder in sets of three and stacked with aluminum spacers to
    slightly offset the angles between them, so that the effective
    horizontal mosaic FWHM of the array is 60(6) minutes. Voids between
    the adjacent plates shall not exceed 0.5 mm.

2.  **Heusler alloy monochromator:** An array of precisely aligned
    Cu~2~MnAl crystals (well annealed so that the (111) Bragg
    reflectivity approaches that expected for ideally imperfect
    crystals) is to be mounted on a standard frame as described in
    section 3.1. The Mn moments in the crystals are to be fully aligned
    by an external magnetic field produced by permanent magnets
    co-mounted with the frame. A polarization efficiency better than 95%
    and reflectivity better than 50% for polarized neutrons at a
    reference energy E~i~ = 15 meV are defined as being acceptable. This
    monochromator assembly is to be procured from a vendor such as ILL
    or ORNL with a demonstrated ability to produce Heusler crystals of
    good performance.

3.  **Optional additional monochromators:** A set of
    potassium-intercalated PG or synthetic mica crystals, whichever is
    more practical, is to be mounted on a standard GMI frame for very
    low-neutron-energy applications. Also to be considered as a possible
    future option is a high-wave-vector-resolution and/or perfect
    crystal focusing arrangement based on silicon or germanium crystals.

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4.  **Monochromator exchanger**

> This device shall enable computer-controlled remote selection of one
> or the other of two crystal monochromator assemblies. Monochromator
> exchange is to take less than 1 minute. During typical operation
> exchange might occur as often as once a week. The exchanger should be
> designed so that either of the monochromators can be removed from the
> incident beam for service while the SNS is operating at full power.

5.  **Monochromator-to-sample supermirror guide**

> A vertically-tapered, vertically-converging supermirror guide, **G4,**
> with a supermirror coating of the largest practical critical angle
> larger than 3θ^Ni^~c~ shall be located on the sample arm between the
> monochromator and sample. It should extend from as close to the
> monochromator as possible to within 400 mm of the sample. It shall be
> 40 mm wide; the inside height as a function of the distance, *x*, from
> the sample shall be given by

$h(x) = h_{s} + \left( h_{m} - h_{s} \right)\ \frac{x}{L_{\text{MS}}}$,

> where *h~s~=*40 mm is the nominal sample height, *h~m~*= 240 mm is the
> monochromator height and *L~MS~* = 1800 mm is the nominal
> monochromator to sample distance. **G4** shall be split into three
> sections, **G4a**, **G4b**, and **G4c**, all mounted on the sample arm
> as described in section 3.1. A computer-controlled exchanger should
> permit remote replacement of the 150 mm long middle section **G4b** by
> a Fermi-chopper module as specified in section 3.6. Additionally there
> should be a computer-controlled exchanger permitting remote
> replacement of the 150 mm long **G4c** section (the closest to the
> sample) by one of a set of Soller collimators as specified in section
> 3.7. The guide sections shall be either evacuated or filled with ^4^He
> gas, wherever this will significantly reduce beam air scattering.
>
> Each guide segment shall be centered and aligned with respect to a
> horizontal reference line connecting the sample rotation axis to the
> monochromator rotation axis. Centering should be accurate to within
> 0.5 mm and alignment accurate to better than 1 minute of arc. All
> guide segments inside the monochromator drum are to be tightly
> embedded in the shielding. Materials that are illuminated by the
> monochromator and visible from the sample position should have the
> smallest possible incoherent scattering cross section.

6.  **Fermi-chopper**

> For high resolution applications, a computer-controlled exchanger
> shall replace guide section **G4b** with a module of matching size
> containing a Fermi-chopper, **T~3~**, designed to reduce the sample
> illumination times to 10 μs \< τ~0~ \< 50 μs. Because this chopper is
> not intended to be energy-selective it should have short, straight
> slots and rotate about a vertical axis in phase with the source at up
> to 480 Hz (8 times the source frequency). The outer diameter of the
> rotor shall be 120 mm or less, and the height of the slotted channel
> should match the exit height of the **G4a** section of guide.

7.  **Collimators**

> When necessary, a computer-controlled exchanger should make it
> possible to replace the guide section **G4c** nearest the sample with
> one of a set of four Soller collimators of identical external
> dimensions. The four collimators should define effective horizontal
> beam divergences of 20\', 40\', 60\', and 120\' respectively.
> Collimator blade thicknesses should be 0.1 mm or less. If feasible,
> the top and bottom surfaces of the collimators should have the same
> super-mirror coatings as guide **G4c**.

8.  **Monochromator shielding**

> The monochromator shall be surrounded by a neutron and gamma-ray
> absorbing composite shielding with a movable beam-port opening that is
> mechanically connected to the sample arm and rotates with it. To the
> extent practical it should be constructed of non-magnetic materials
> that have minimal long term neutron activation cross sections. The
> range of take-off angles accessible through the beam-port should be
> -5° to 120°. It should take less than 2 min. to change the take-off
> angle from one extreme to the other. The combined monochromator
> crystal and beam-port rotation should define the monochromator crystal
> take-off angle to ± 0.02^o^ or less. Whether the shielding mechanical
> design is to be based on a drum, pie-wedge section or other concept is
> yet to be determined.
>
> The beam-port opening in the shield should be of internal dimensions
> that accommodate the converging guide **G4a-c**, the Fermi-chopper and
> the collimators. The shield design should also provide for
> incorporation of the remote exchange mechanisms. Shielding must be
> fitted tightly around all neutron optics elements attached to the
> sample arm as specified in sections 3.5-3.7 (with radiation steps
> where necessary) so that neutrons from the monochromator either pass
> through these elements or are absorbed in the shielding. The inner
> dimension of the shield should be such as to accommodate the
> monochromator crystal exchange mechanism with two monochromator
> crystal assemblies. Radiation protection requirements will determine
> the outer radius of the shield. It must contain neutron and gamma ray
> absorbing material sufficient to reduce the radiation rate and the
> background to acceptable levels: i.e. the radiation dose rate, and
> background outside the shielding and outside of monochromatic beam
> should be no more than 5 mrem/hr at a distance 300 mm from the neutron
> beam and in compliance with all SNS radiation protection requirements
> and ALARA. Shield thickness should not exceed 1400 mm, so that a
> clearance of at least 400 mm between the shield and the sample axis is
> provided. Internal shield design should be such that the amount of the
> material inside the shield exposed to the incident neutron beam is
> minimized; all shielding around the monochromator that can be viewed
> from the sample position must be recessed in such a way that it is not
> directly illuminated by the incident neutron beam. A convenient access
> to the monochromators and other beam-line neutron optic elements for
> servicing and replacement must be provided.
>
> The location and characteristics of the beam dump or "get lost" pipe
> (whichever is applicable) must be chosen to minimize its contribution
> to the detector count rate. In addition, an interlocked radiation
> exclusion zone around the instrument is to be defined in collaboration
> with the SNS operations staff.

9.  **Beam optics between collimator and sample**

> A neutron optical bench shall be permanently attached to the sample
> arm and/or to the beam-port outside the shielding and aligned to
> better than 1 minute of arc with respect to a horizontal reference
> line connecting the sample rotation axis to the monochromator rotation
> axis as described in section 3.5. All components listed below are to
> be mounted on this bench downstream of the **G4** super-mirror guide.
> Components 3.9.1-3.9.3 shall be semi-permanently mounted; their
> combined thickness must not exceed 80 mm.

1.  A beam monitor with a sensitive area larger than the exit aperture
    of the guide **G4c** and with a wavelength-proportional sensitivity
    that is no greater than 10^-5^ at 15 meV.

2.  A four position beam attenuator controlled from the main instrument
    control computer and capable of introducing three different planar
    objects into the beam. Two of the positions should provide 10 times
    and 100 times attenuation of the beam respectively at 15 meV. These
    two attenuators shall be permanently installed in the exchanger. The
    third position is to be slot that can hold a plate of width 40 mm,
    height 100 mm and between 1 mm and 10 mm thick. When selected by the
    attenuator exchanger this plate shall be positioned in the center of
    the beam to within 1 mm. The fourth position shall be a local beam
    shutter.

3.  A computer-controlled, variable-opening, thermal neutron aperture
    covered with layer of LiF on the side facing the monochromator
    crystal. The aperture must be centered in the beam to within 0.5 mm
    and should have four independent degrees of freedom controlling the
    right, left, top and bottom opening with a positioning accuracy of
    better than 0.5 mm. The design should permit the width and height of
    the aperture to be varied from fully closed to the full width and
    height of the beam as defined by the exit aperture of the guide
    **G4c** as specified in section 3.5.

4.  A computer-controlled aluminum flipper coil, not more than 20 mm
    thick, designed to rotate the neutron polarization in the incident
    beam by 0°-180°.

5.  Auxiliary neutron optics components (of a total length not exceeding
    150 mm) required for applications to be specified in the future.

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4.  **Sample stage**

> The sample stage shall be rigidly attached to the sample arm and
> supported on the floor in such a way that it can move with the arm
> without tilting as it rotates to beam position defined by the
> monochromator crystal take-off angle. The positional accuracy of the
> sample stage should correspond to the same 0.02° precision as for the
> combined monochromator crystal and sample arm setting angle, as
> specified in section 3.8. Sample area shall be surrounded with
> interlocked shielding that reduces radiation levels to 5 mrem/hr or
> less and meets all SNS radiation protection requirements.

1.  **Space and location**

> The space available for sample stage positioning must allow
> monochromator crystal take-off angles covering the range
> -5°\<2θ\<120°. Space for the power supplies, pumps and other auxiliary
> equipment required for both polarized beam operation and special
> sample environments must also be provided on the sample floor. The
> distance from the sample rotation axis to the monochromator crystal
> rotation axis shall be variable within restricted limits which are to
> be defined. It should be no greater than necessary to accommodate a
> Fermi-chopper, a Soller collimator, a neutron beam monitor, and
> polarized-beam equipment (such as a flipper) as specified in sections
> 3.5-3.9. A monochromator-to-sample distance *L~MS~* = 1800 mm is
> defined as nominal.

2.  **Degrees of freedom provided.**

    1.  Sample rotation 0-360^o^ with an accuracy of 0.005 degrees.

    2.  Tilt of sample table ±12^o^ about two mutually perpendicular
        horizontal axes. Tilt accuracy must be better than 0.1^o^ for
        loads in the range specified in section 4.3; the effective
        rotation axes must lie within 20 mm of beam center height.

    3.  Vertical translation of ±40 mm above and below the beam center
        with positional accuracy better than 1 mm.

    4.  Horizontal translation of ±20 mm along two mutually
        perpendicular horizontal directions parallel to the sample tilt
        axes, both with positional accuracy better than 0.5 mm.

3.  **Dimensions and load capacity.**

> The sample stage mounting surface shall be at least 152 mm below the
> beam center. Its on-axis load capacity shall be \>500 kg. A (maximum)
> horizontal torque of 5·10^2^ N·m should result in less than a 0.1^o^
> tilt of the sample rotation axis from the vertical.

4.  **Materials requirement**

> Sample table shall be made of non-magnetic materials. The force on any
> of its elements in a magnetic field gradient of 10 Gauss/mm should not
> exceed 1 N.

5.  **Guide field**

> A computer-controlled coils capable of generating either a vertical or
> a horizontal magnetic field larger than 10 Gauss throughout the
> neutron beam path around sample are to be provided. Coils should be
> mountable on the sample table and be large enough to accommodate a
> standard sample environment (ie provide a horizontal clearance of at
> least 400 mm in diameter around the sample axis).

5.  **Analyzer-Detector system**

    1.  **General principle**

> Analysis of the scattered neutron energy will be by time-of-flight in
> a secondary flight-path of length *L~SD~* = 4500 ± 4 mm as measured
> from the sample axis to the individual detector axis. The secondary
> flight-path shall include a variable vertical aperture after the
> sample, shielding, a gas-tight or vacuum-tight flight vessel
> containing either a radial collimator or a transmission polarizer
> assembly and a detector array as specified below. The secondary
> flight-path (analyzer) vessel shall be mobile, and designed to move on
> the floor in such a way that: (i) for all monochromator crystal
> take-off angles the axis of the cylindrical detector array remains
> vertical and coincides with the sample axis to an accuracy of better
> than 2 mm (ii) the detector bank can be sequentially moved (as
> specified by the experimenter) to those positions where the range of
> sample scattering angles accepted by detectors is best matched to the
> measurement.

2.  **Detector bank**

> The detector bank shall consist of a cylindrical array of identical,
> vertically mounted, one-dimensional, position-sensitive, tube-type
> ^3^He detectors centered on the sample axis and symmetric about the
> horizontal scattering plane. The angular size of the individual
> detector pixels (as seen from the sample position) shall not exceed 20
> minutes of arc in either the vertical or horizontal direction. Each
> detector shall cover a scattering angle of at least ± 7.5° in the
> vertical direction; the horizontal angular coverage of the entire
> detector array will be at least 60°. Detectors shall have partial
> pressure of ^3^He gas and thickness to achieve 90% detection
> efficiency for 15 meV neutrons.
>
> An array of 190 or more 64-pixel, position-sensitive detectors 20 mm
> to 25 mm in diameter and 1200 mm to 1300 mm long satisfying the above
> specifications are to be purchased from an established detector
> manufacturer. They shall be mounted with their axes vertical to within
> 5 minutes of arc and positioned with an accuracy of 2 mm on a 4500 mm
> radius circle in the horizontal plane. This is also the accuracy to
> which the detectors are to be co-centered at the nominal beam-sample
> height. Voids between adjacent detector tubes are not to exceed 1 mm.
>
> The detector array shall be fixed inside the mobile analyzer vessel.
> The vessel design will allow the detector array rotation around an
> axis concentric with the sample axis to within 2 mm with the accuracy
> of angular positioning better than 0.02°. Detector voltage supplies,
> preamplifiers and primary acquisition electronics shall be mounted on
> the analyzer vessel and move with it to reduce the number of cables
> connecting the mobile detector array to the stationary part of the
> data acquisition system to 1 or 2 high-speed, optical or other,
> communication lines.

3.  **Analyzer vessel**

> Except for the initial 400 mm downstream of the sample axis, the path
> of the neutrons scattered by the sample shall be contained within a
> mobile secondary flight-path (analyzer) vessel which is to be either
> evacuated or ^4^He/Ar gas-filled, to minimize beam loss and background
> from air scattering. The auxiliary equipment needed to either maintain
> vacuum or gas pressure shall be permanently mounted on the vessel and
> shall move with it. Either a radial collimator or a transmission
> polarization analysis assembly shall be positioned in the scattered
> beam inside the flight vessel, with its upstream face at a nominal
> distance of 400 mm from the sample axis, as specified in sections
> 5.6-5.7. The vessel shall be equipped with a computer-controlled
> automated exchanger that selects either one of the four radial
> collimators or one of the two polarization analysis assemblies.

1.  **Materials:** The analyzer vessel shall be made of high-strength
    aluminum alloy or similar non-magnetic material with a low neutron
    activation cross section. Its inner walls and all parts of the
    collimator or polarization analysis assembly that are visible to the
    detector array should be covered with a neutron-absorbing material
    such as B~4~C or LiF. The scattered beam entrance window on its
    upstream face should be made of high neutron transparency, high
    strength aluminum alloy and be of the minimal thickness necessary to
    support either vacuum or a small over-pressure of gas within the
    vessel.

2.  **Dimensions:** The size and the shape of the inner and outer
    cylindrical walls of the flight vessel shall be designed to (i)
    allow either a one of the radial collimators or one of the
    polarization analysis assemblies be positioned with its upstream
    face 400 mm from the sample; (ii) provide space for the automatic
    exchanger and the collimators and polarization analysis assemblies
    that are not in use, and (iii) accommodate the detector array which
    is to be rigidly attached the vessel to the vessel outer wall
    inside. A removable port(s) are to be provided for convenient access
    to the automatic exchanger and the detector array. The flat walls on
    the sides, top and bottom of the vessel are to have inner dimensions
    which restrict the area of sample illumination to the size of the
    detector array. For example, the inner height, *h(x)*, of the vessel
    should vary with distance, *x*, from the sample axis in accord with
    the expression

> $h(x) = h_{s} + \left( h_{d} - h_{s} \right)\ \frac{x}{L_{\text{SD}}}$,
>
> where *h~s~=*40 mm is the nominal sample height, *h~d~*= 1280 mm the
> nominal detector height and *L~SD~* = 4500 mm the sample to detector
> distance.

3.  **Position:** The analyzer vessel shall move on the floor following
    the sample arm so that the axis of the cylindrical detector array
    coincides with the sample axis with a positioning accuracy of better
    than 2 mm, as described in section 5.1. The accuracy of the detector
    bank angular positioning with respect to the axis of the beam
    incident on the sample should be better than 0.02° and should be
    reproducible after 1000 analyzer vessel movements. If not restricted
    by the incident guide and associated shielding, sample scattering
    angle extreme positions of -5° and +120° should be accessible to at
    least one detector for all monochromator take-off angles. It should
    take less than 2 minutes to move the analyzer vessel with detector
    bank between the extreme angular positions. Vessel support and
    moving systems shall be chosen to minimize the cost of construction,
    operation and maintenance while at the same time meeting all of the
    above-listed specifications.

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4.  **Variable vertical aperture after sample**

> Upstream of the secondary flight-path shielding (but as close to the
> sample as practical) there shall be a computer-controlled slit capable
> of restricting the height of the beam scattered by the sample from
> *h*~min~= 0 mm to *h*~max~= 100 mm. This slit should be centered to
> within 1 mm of the beam-center height and have top and bottom
> apertures that are independently motorized and controlled. It can
> either be an independently mounted device made of 40 mm thick
> B~4~C-rich material and covered with LiF on the side facing the sample
> or a mobile extension of the analyzer shielding that can be positioned
> as close to the sample as needed.

5.  **Shielding**

> Shielding made of high neutron cross-section materials shall be placed
> around the analyzer vessel. This shielding shall either be a
> stationary structure enclosing all possible analyzer positions or be
> attached to the mobile analyzer vessel itself; the choice is to be
> made on the basis of practicality and cost-efficiency. In either case,
> the shielding inner surface shall be covered with a
> thermal-neutron-absorbing material such as cadmium or LiF. A
> background count rate of 1 count/min/detector when the SNS is
> operating but both the beamline shutter and the shielding entrance
> window are closed is defined as being acceptable. The interior height
> of the stationary shielding must be sufficient to contain the analyzer
> vessel and all auxiliary equipment mounted on it, as specified in
> section 5.3. Also, its top must be modular and allow for easy access
> to the analyzer vessel for maintenance and, if necessary, replacement
> of the vessel and/or its components. If MCNP-X neutronics calculations
> establish the necessity of a "get-lost" pipe, it should be
> incorporated into the shield design.

1.  **Dimensions and position:** The shielding should start as close as
    possible to the variable vertical aperture after the sample
    specified in 5.4. The distance from the sample axis to the upstream
    face of the shielding shall be such that the analyzer vessel can be
    positioned with the upstream face of the radial collimator or
    polarization analysis assembly (whichever is in place) 400 mm from
    the sample axis. This shielding should have a 100 mm tall scattered
    beam entrance window and a computer-controlled horizontal aperture
    of width and position that can be varied so that a selected number
    of detectors (from a minimum of 1 to a maximum of all detectors in
    the array) are visible from the sample position. It should be so
    designed that - if not restricted by the incident guide and its
    associated shielding - extreme sample scattering angles of -5° and
    +120° are accessible to at least one detector at all monochromator
    take-off angles as specified in section 5.3.3. A sufficient
    clearance downstream the flight vessel should be provided to permit
    easy assembly and maintenance of the detectors and detector
    electronics.

2.  **Beam stop:** In some positions of the analyzer vessel the axis of
    the primary beam could intersect the detector array. It will
    therefore be necessary to have either a primary beam stop or a
    "get-lost" pipe to prevent the primary beam from either directly
    impinging on the detector array or creating an unacceptable
    background of primary beam neutrons scattered into the detector
    array. A beam stop should be designed to produce as little neutron
    and hard gamma radiation as possible; its exterior width should be
    minimized and its position chosen so that it cannot scatter neutrons
    into any of the active detection channels.

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6.  **Radial collimators after sample**

> Immediately behind the upstream face of the analyzer vessel there
> shall be a four-position collimator exchanger capable of accurately
> positioning any one of four radial collimators or, alternatively, one
> of two polarization analyzer assemblies in the scattered beam. In all
> positions the collimator axes should be concentric with the sample
> axis to better than 2 mm. Changes from one collimator or polarization
> analyzer to another are to be effectuated from a control computer and
> should take less than 30 seconds. All collimators are to be embedded
> in high boron content neutron shielding material in such a way that
> neutrons either pass through the window of the collimator or are
> absorbed. In addition, the lateral dimensions of their entrance
> windows should match the lateral dimensions of the entrance window of
> the flight vessel and their internal dimensions should match the
> dimensions of the scattered beam illuminating the detectors in the
> same way as the inside surfaces of the analyzer vessel match the
> scattered beam dimensions, as specified in section 5.3.2. The spacing
> between blades is to be determined by the expression

$d = \alpha\ell$,

> where $\ell =$`<!-- -->`{=html}200 mm is the length of the collimator
> blades and *α* is the effective beam divergence. Horizontal divergence
> angles *α *for the four collimators shall be 20\', 40\', 60\' and 120'
> respectively. Blade thicknesses should be 0.1 mm or less.
>
> All the radial collimators are to be positioned with the sample
> rotation axis as their focal point to within 2 mm and should be
> parallel to one another to within 0.01 degree. A line passing through
> the central blades of the collimators should also pass through the
> sample rotation axis to within 2 mm.

7.  **Broadband transmission polarizers.**

> It shall be possible to place either of two broadband, multi-channel
> supermirror transmission polarization analysis assemblies in the same
> position as the radial collimators (i.e. immediately behind the
> upstream wall of the analyzer vessel, at 400 mm from the sample axis)
> using the same computer-controlled collimator exchange mechanism. One
> of the two polarization analysis assemblies is to be configured for
> optimum performance at 15 meV; the other at 7.5 meV. It should also be
> possible to substitute the polarization analysis assemblies for radial
> collimators in the exchanger. Changing from one combination of
> polarization analyzers and collimators to another will be done
> manually and should not take more than 30 minutes to complete. Like
> the collimators, the polarization analyzers are to be embedded in a
> boron-rich neutron shielding material so that neutrons either pass
> through the polarizing windows or are absorbed.

1.  **Polarization analysis assembly:** Each polarization analysis
    assembly is to consist of 19 identical channels mounted in a common
    magnetic frame supplying a permanent magnetic field of at least 300
    Gauss; i.e. a field sufficient to magnetically saturate the
    polarization-sensitive supermirror coatings in all channels. Each
    channel is to be 20 mm in over-all width and have a height profile
    that matches the scattered beam height as specified in section
    5.3.2. The height should not, however, exceed 200 ± 10 mm at its
    downstream end. The channels should be equally spaced on the
    circumference of a circle centered at the sample position with an
    accuracy of 2 mm, and co-leveled with the sample height with the
    same accuracy. Tight fitting, wedge-shaped neutron absorbing spacers
    are to be placed between channels to assure that all neutrons
    incident on the detectors pass through and not between the channels.
    Sample scattered neutrons passing through the channels will be split
    into two separate beams of opposite polarization. The channels
    should be designed so that the oppositely polarized beams from each
    channel are fully separated at the detector position but are not
    overlapped by beams from adjacent channels for scattered neutron
    energies 3\< E~f~\<30 meV.

2.  **Individual polarization analysis channel:** Each channel shall
    consist of a 20 mm wide and 150 mm long collimator immediately
    followed by a stack of 20 mm wide, polarization-sensitive,
    supermirror-coated, thin silicon wafers 50 mm long and tall enough
    to accept the full scattered beam height as specified in section
    5.7. Aluminum spacers are to be used to bend the silicon wafer
    stacks to a horizontal cylindrical curvature that optimizes the
    polarization analysis efficiency of the channel at the nominal
    neutron energy for which it is designed. The collimator and
    polarization analyzer are to be placed in a rigid frame and
    co-aligned so as to achieve optimum beam transmission and
    polarization analysis efficiency at the nominal neutron energy. A
    choice of 10\', 20\' or 40\' collimation should be provided for each
    channel. The critical angle of the supermirror coating for one
    neutron polarization direction should be at least 3θ^Ni^~c~ (or
    larger if possible) and for the other it should be no larger than
    θ^Ni^~c~ (or smaller if possible). Over-all, the transmission of the
    polarized collimated beam through the channel is to be better than
    90% for energies 3\<E~f~\< 30 meV. The center-line of every
    polarization analyzer collimator should pass through the sample
    rotation axis to within 2 mm.

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6.  **Instrument Control and Data Acquisition**

> Three independent computer systems are to be supplied with the
> instrument. To the extent possible, standard software developed by the
> SNS staff is to be utilized.

1.  **Instrument Control System.** An Instrument Control Program (ICP)
    running on a dedicated computer shall control the status and
    operation of all instrument systems as specified in this document,
    including any automated sample environments needed for particular
    measurements. The ICP shall communicate with the data acquisition
    program (section 6.2) to provide information about the instrument
    configuration and to synchronize and up-date their mutual status
    during the course of the experiment. The ICP shall also communicate
    with the experiment planning and data analysis program (section 6.3)
    to make it possible for the experimenter to pre-select optimum
    instrument configurations and input parameters for the planned
    measurement.

2.  **Data Acquisition System (DAS).** There shall be a separate,
    dedicated computer with an advanced high-capacity storage system
    that is able to communicate with the detector electronics and
    collect, pre-process and store the data from the individual
    detectors. Data is to be stored in files using the HDF-type
    (hierarchical data) format common to all SNS instruments. Along with
    the data, the files should contain headers with a complete
    description of the instrument configuration and instrument
    parameters provided by the ICP.

3.  **Experiment Planning and Data Analysis Program (EPDAP).** HYSPEC
    shall have a dedicated and integrated software package, EPDAP, to
    plan measurements so as to take optimal advantage of the wide-angle,
    multi-channel TOF analyzing system and also to analyze the data. The
    EPDAP should run on a separate, dedicated computer equipped with an
    extensive set of the peripheral devices for data transfer and
    visualization. It should be able to communicate with the ICP to
    export/import the instrument parameters and with the DAS to read the
    data for analysis and visualization.

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7.  **System Wide Requirements**

    1.  **Hard and soft limits.** All instrument degrees of freedom must
        be equipped with soft and/or hardware limits that prevent
        collisions but allow a full range of physically achievable
        positions. Sample rotation is a special case where hardware
        limits must be variable to allow for the different constraints
        imposed by different sample environments.

    2.  **Automated calibration and alignment.** There should be an
        automated detector calibration procedure and an automated
        alignment protocol for all degrees of freedom of the instrument.

    3.  **Permanent electrical wiring.** The number of cables should be
        minimized; wherever possible optical communication lines are to
        be used. All wiring is to be permanently installed and is to
        comply with all applicable industry and SNS standards.

    4.  **Crane.** There must be an overhead crane capable of lifting
        weights of more than 1 metric ton such as, for example, major
        secondary flight-path instrument components. It should also be
        capable of lifting heavy (and more than 1500 mm tall) sample
        environment devices - such as, for example, cryomagnets - and
        mounting them on the sample table. Crane coverage should extend
        over the monochromator shielding, the sample table and the
        secondary flight-path systems.

    5.  **Radiation Safety Exclusion zone.** In accordance with the "as
        low as reasonably achievable" radiation safety requirements, the
        instrument is to be surrounded by an interlocked exclusion zone
        within which personnel will not be permitted when the primary
        shutter is open and the beam is on. Details are to be specified
        by SNS Health Physics.

^(1)^ Metric units have been used throughout this document. Where
standard stock sizes of materials differ from those specifiied, the
closest four-digit decimal inch value is to apply.

**Appendix D. HYSPEC Estimated Budget and Funding Profile**

<table>
<colgroup>
<col style="width: 15%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
</colgroup>
<tbody>
<tr class="odd">
<td><blockquote>
<p><strong>ITEM</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Direct cost in FY03 $</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Burden Allowance @10%</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Contingency Factor</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Contingency</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>TOTAL w/ Burden &amp; Conting.</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY03</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY04</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY05</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY06</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY07</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>Esc to At Year $ FY08</strong></p>
</blockquote></td>
<td><blockquote>
<p><strong>At Year Total</strong></p>
</blockquote></td>
</tr>
<tr class="even">
<td><strong>Technical Construction</strong></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td><strong> </strong></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
</tr>
<tr class="odd">
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td> </td>
</tr>
<tr class="even">
<td><strong>Primary Flight Path</strong></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td> </td>
</tr>
<tr class="odd">
<td>T0 chopper</td>
<td>218</td>
<td>22</td>
<td>25%</td>
<td>60</td>
<td>300</td>
<td>-</td>
<td>-</td>
<td>316</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>316</td>
</tr>
<tr class="even">
<td>Frame overlap chopper</td>
<td>131</td>
<td>13</td>
<td>25%</td>
<td>36</td>
<td>180</td>
<td>-</td>
<td>-</td>
<td>190</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>190</td>
</tr>
<tr class="odd">
<td>Counter-rotating disk choppers</td>
<td>364</td>
<td>36</td>
<td>25%</td>
<td>100</td>
<td>500</td>
<td>-</td>
<td>-</td>
<td>527</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>527</td>
</tr>
<tr class="even">
<td>Fermi chopper</td>
<td>364</td>
<td>36</td>
<td>25%</td>
<td>100</td>
<td>500</td>
<td>-</td>
<td>-</td>
<td>527</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>527</td>
</tr>
<tr class="odd">
<td>Steel jacketed m=3 guides</td>
<td>291</td>
<td>29</td>
<td>25%</td>
<td>80</td>
<td>400</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>434</td>
<td>-</td>
<td>-</td>
<td>434</td>
</tr>
<tr class="even">
<td>Shutter insert m=3 guide</td>
<td>131</td>
<td>13</td>
<td>25%</td>
<td>36</td>
<td>180</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>195</td>
<td>-</td>
<td>-</td>
<td>195</td>
</tr>
<tr class="odd">
<td>Guide shielding</td>
<td>873</td>
<td>87</td>
<td>25%</td>
<td>240</td>
<td>1,200</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>1,301</td>
<td>-</td>
<td>-</td>
<td>1,301</td>
</tr>
<tr class="even">
<td>Beam monitors</td>
<td>29</td>
<td>3</td>
<td>25%</td>
<td>8</td>
<td>40</td>
<td>-</td>
<td>-</td>
<td>42</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>42</td>
</tr>
<tr class="odd">
<td>Sub total</td>
<td>2,400</td>
<td>240</td>
<td> </td>
<td>660</td>
<td>3,300</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>3,533</td>
</tr>
<tr class="even">
<td><strong>Monochromator Section</strong></td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="odd">
<td>Monochromator Drum Shield</td>
<td>945</td>
<td>95</td>
<td>25%</td>
<td>260</td>
<td>1,300</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>1,410</td>
<td>-</td>
<td>-</td>
<td>1,410</td>
</tr>
<tr class="even">
<td>Crystals and holders</td>
<td>182</td>
<td>18</td>
<td>25%</td>
<td>50</td>
<td>250</td>
<td>-</td>
<td>-</td>
<td>264</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>264</td>
</tr>
<tr class="odd">
<td>Tapered m=3 guide</td>
<td>73</td>
<td>7</td>
<td>25%</td>
<td>20</td>
<td>100</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>108</td>
<td>-</td>
<td>-</td>
<td>108</td>
</tr>
<tr class="even">
<td>Collimators</td>
<td>36</td>
<td>4</td>
<td>25%</td>
<td>10</td>
<td>50</td>
<td>-</td>
<td>-</td>
<td>53</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>53</td>
</tr>
<tr class="odd">
<td>Beam monitor and slits</td>
<td>44</td>
<td>4</td>
<td>25%</td>
<td>12</td>
<td>60</td>
<td>-</td>
<td>-</td>
<td>63</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>63</td>
</tr>
<tr class="even">
<td>Shielded get-lost pipe</td>
<td>436</td>
<td>44</td>
<td>25%</td>
<td>120</td>
<td>600</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>651</td>
<td>-</td>
<td>-</td>
<td>651</td>
</tr>
<tr class="odd">
<td>Beam stop</td>
<td>145</td>
<td>15</td>
<td>25%</td>
<td>40</td>
<td>200</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>217</td>
<td>-</td>
<td>-</td>
<td>217</td>
</tr>
<tr class="even">
<td>Sub total</td>
<td>1,862</td>
<td>186</td>
<td> </td>
<td>512</td>
<td>2,560</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>2,765</td>
</tr>
<tr class="odd">
<td><strong>Sample Stage</strong></td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td>Goniometer and support</td>
<td>109</td>
<td>11</td>
<td>25%</td>
<td>30</td>
<td>150</td>
<td>-</td>
<td>-</td>
<td>158</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>158</td>
</tr>
<tr class="odd">
<td>Removable shielding</td>
<td>73</td>
<td>7</td>
<td>25%</td>
<td>20</td>
<td>100</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>108</td>
<td>-</td>
<td>-</td>
<td>108</td>
</tr>
<tr class="even">
<td>Ancillary equipment</td>
<td>76</td>
<td>8</td>
<td>20%</td>
<td>17</td>
<td>100</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>111</td>
<td>-</td>
<td>111</td>
</tr>
<tr class="odd">
<td>Sub total</td>
<td>258</td>
<td>26</td>
<td> </td>
<td>67</td>
<td>350</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>378</td>
</tr>
<tr class="even">
<td><strong>Detector System</strong></td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="odd">
<td>190 position-sensitive detectors</td>
<td>415</td>
<td>41</td>
<td>25%</td>
<td>114</td>
<td>570</td>
<td>-</td>
<td>-</td>
<td>601</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>601</td>
</tr>
<tr class="even">
<td>Detector support structure</td>
<td>44</td>
<td>4</td>
<td>25%</td>
<td>12</td>
<td>60</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>65</td>
<td>-</td>
<td>-</td>
<td>65</td>
</tr>
<tr class="odd">
<td>Collimators/positioner</td>
<td>145</td>
<td>15</td>
<td>25%</td>
<td>40</td>
<td>200</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>217</td>
<td>-</td>
<td>-</td>
<td>217</td>
</tr>
<tr class="even">
<td>19 Polarization analyzers</td>
<td>582</td>
<td>58</td>
<td>25%</td>
<td>160</td>
<td>800</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>867</td>
<td>-</td>
<td>-</td>
<td>867</td>
</tr>
<tr class="odd">
<td>Rotating Detector vessel</td>
<td>582</td>
<td>58</td>
<td>25%</td>
<td>160</td>
<td>800</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>867</td>
<td>-</td>
<td>-</td>
<td>867</td>
</tr>
<tr class="even">
<td>Beam controls-DAQ</td>
<td>80</td>
<td>8</td>
<td>25%</td>
<td>22</td>
<td>110</td>
<td>-</td>
<td>-</td>
<td>116</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>116</td>
</tr>
<tr class="odd">
<td>Detector shield</td>
<td>655</td>
<td>65</td>
<td>25%</td>
<td>180</td>
<td>900</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>976</td>
<td>-</td>
<td>-</td>
<td>976</td>
</tr>
<tr class="even">
<td>Sub total</td>
<td>2,502</td>
<td>250</td>
<td> </td>
<td>688</td>
<td>3,440</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>3,710</td>
</tr>
<tr class="odd">
<td><strong>Data Collection System</strong></td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td>Mezzanine</td>
<td>45</td>
<td>5</td>
<td>20%</td>
<td>10</td>
<td>60</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>68</td>
<td>68</td>
</tr>
<tr class="odd">
<td>Control cabin</td>
<td>30</td>
<td>3</td>
<td>20%</td>
<td>7</td>
<td>40</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>46</td>
<td>46</td>
</tr>
<tr class="even">
<td>Furnishings</td>
<td>8</td>
<td>1</td>
<td>20%</td>
<td>2</td>
<td>10</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>11</td>
<td>11</td>
</tr>
<tr class="odd">
<td>Miscellaneous</td>
<td>29</td>
<td>3</td>
<td>25%</td>
<td>8</td>
<td>40</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>11</td>
<td>11</td>
<td>23</td>
<td>45</td>
</tr>
<tr class="even">
<td>R&amp;D; choppers/polarizers</td>
<td>182</td>
<td>18</td>
<td>25%</td>
<td>50</td>
<td>250</td>
<td>-</td>
<td>256</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>256</td>
</tr>
<tr class="odd">
<td>Sub total</td>
<td>294</td>
<td>29</td>
<td> </td>
<td>76</td>
<td>400</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>426</td>
</tr>
<tr class="even">
<td>CAPITAL TOTAL</td>
<td><strong>7,315</strong></td>
<td><strong>732</strong></td>
<td><strong>25%</strong></td>
<td><strong>2,003</strong></td>
<td><strong>10,050</strong></td>
<td>-</td>
<td>256</td>
<td>2,858</td>
<td>7,427</td>
<td>122</td>
<td>148</td>
<td><strong>10,812</strong></td>
</tr>
<tr class="odd">
<td> </td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td><strong>Labor</strong></td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="odd">
<td>Installation technicians</td>
<td>1,061</td>
<td>106</td>
<td>20%</td>
<td>233</td>
<td>1,400</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>445</td>
<td>1,140</td>
<td>1,585</td>
</tr>
<tr class="even">
<td><strong>LABOR TOAL</strong></td>
<td><strong>1,061</strong></td>
<td><strong>106</strong></td>
<td><strong>0</strong></td>
<td><strong>233</strong></td>
<td><strong>1,400</strong></td>
<td><strong>-</strong></td>
<td><strong>-</strong></td>
<td><strong>-</strong></td>
<td><strong>-</strong></td>
<td>445</td>
<td>1,140</td>
<td><strong>1,585</strong></td>
</tr>
<tr class="odd">
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td> </td>
</tr>
<tr class="even">
<td><strong>Technical Construction Total</strong></td>
<td><strong>8,376</strong></td>
<td><strong>838</strong></td>
<td><strong>0</strong></td>
<td><strong>2,236</strong></td>
<td><strong>11,450</strong></td>
<td><strong>-</strong></td>
<td>256</td>
<td>2,858</td>
<td>7,427</td>
<td>567</td>
<td>1,288</td>
<td><strong>12,398</strong></td>
</tr>
<tr class="odd">
<td> </td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td><strong>Project Management &amp; Engineering</strong></td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="odd">
<td> </td>
<td>-</td>
<td>-</td>
<td></td>
<td>-</td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td>Project Management</td>
<td>661</td>
<td>66</td>
<td>10%</td>
<td>73</td>
<td>800</td>
<td>-</td>
<td>164</td>
<td>169</td>
<td>173</td>
<td>178</td>
<td>182</td>
<td>867</td>
</tr>
<tr class="odd">
<td>Project Engineer/Scientist</td>
<td>661</td>
<td>66</td>
<td>10%</td>
<td>73</td>
<td>800</td>
<td>80</td>
<td>246</td>
<td>169</td>
<td>173</td>
<td>178</td>
<td>-</td>
<td>846</td>
</tr>
<tr class="even">
<td>Designer/Engineer</td>
<td>579</td>
<td>58</td>
<td>10%</td>
<td>64</td>
<td>700</td>
<td>50</td>
<td>205</td>
<td>211</td>
<td>217</td>
<td>56</td>
<td>-</td>
<td>738</td>
</tr>
<tr class="odd">
<td>ORNL shielding studies</td>
<td>207</td>
<td>21</td>
<td>10%</td>
<td>23</td>
<td>250</td>
<td>250</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>250</td>
</tr>
<tr class="even">
<td>ORNL support/liason</td>
<td>103</td>
<td>10</td>
<td>10%</td>
<td>11</td>
<td>125</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>143</td>
<td>143</td>
</tr>
<tr class="odd">
<td>Software</td>
<td>227</td>
<td>23</td>
<td>20%</td>
<td>50</td>
<td>300</td>
<td>-</td>
<td>-</td>
<td>79</td>
<td>81</td>
<td>83</td>
<td>86</td>
<td>329</td>
</tr>
<tr class="even">
<td>Travel</td>
<td>269</td>
<td>27</td>
<td>10%</td>
<td>30</td>
<td>325</td>
<td>25</td>
<td>62</td>
<td>63</td>
<td>65</td>
<td>67</td>
<td>68</td>
<td>350</td>
</tr>
<tr class="odd">
<td><strong>Proj. Mgt &amp; Engrg. Total</strong></td>
<td><strong>2,700</strong></td>
<td><strong>300</strong></td>
<td><strong>10%</strong></td>
<td><strong>300</strong></td>
<td><strong>3,300</strong></td>
<td>380</td>
<td>615</td>
<td>628</td>
<td>645</td>
<td>940</td>
<td>1,551</td>
<td><strong>4,758</strong></td>
</tr>
<tr class="even">
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="odd">
<td><strong>Project TEC</strong></td>
<td><strong>11,076</strong></td>
<td><strong>1,138</strong></td>
<td><strong> </strong></td>
<td><strong>2,536</strong></td>
<td><strong>14,750</strong></td>
<td><strong>380</strong></td>
<td><strong>871</strong></td>
<td><strong>3,486</strong></td>
<td><strong>8,072</strong></td>
<td><strong>1,507</strong></td>
<td><strong>2,839</strong></td>
<td><strong>17,156</strong></td>
</tr>
<tr class="even">
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
<td> </td>
</tr>
<tr class="odd">
<td><strong>Other Costs</strong></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
<td>-</td>
</tr>
<tr class="even">
<td>Program Development</td>
<td>826</td>
<td>83</td>
<td>10%</td>
<td>91</td>
<td>1,000</td>
<td>-</td>
<td>205</td>
<td>211</td>
<td>217</td>
<td>222</td>
<td>228</td>
<td>1,083</td>
</tr>
<tr class="odd">
<td><strong>OTHER TOTAL</strong></td>
<td><strong>826</strong></td>
<td><strong>83</strong></td>
<td><strong> </strong></td>
<td><strong>91</strong></td>
<td><strong>1,000</strong></td>
<td><strong>-</strong></td>
<td><strong>205</strong></td>
<td><strong>211</strong></td>
<td><strong>217</strong></td>
<td><strong>222</strong></td>
<td><strong>228</strong></td>
<td><strong>1,083</strong></td>
</tr>
<tr class="even">
<td> </td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td> </td>
</tr>
<tr class="odd">
<td><strong>Total Project Cost (TPC)</strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong>15,750</strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong> </strong></td>
<td><strong>18,239</strong></td>
</tr>
</tbody>
</table>

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