LETTER OF INTENT

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

**for the Spallation Neutron Source**

# INTRODUCTION :

The most informative neutron scattering investigations of the
atomic-scale dynamical properties of crystalline solids nearly always
require single crystal samples and -- to date - have mostly been carried
out on crystal spectrometers at high-flux, reactor-based, steady-state
neutron sources. Because such measurements tend to be made with small
samples and are invariably flux-limited, the spectrometers typically
employ focussing Bragg optics to concentrate the neutron beam on the
sample. In the not too distant future the high-luminosity pulsed
Spallation Neutron Source (SNS) at Oak Ridge will provide intense
neutron beams with time-averaged fluxes equal to those at medium-flux
reactors. Recognizing that the SNS will open new opportunities for
neutron scattering, an Instrument Development Team (IDT) composed of
national laboratory and university based scientists has been formed with
the objective of designing and building a spectrometer specifically
optimized for pulsed beam investigations of the microscopic dynamics of
small, single crystal samples. Drawing upon experience acquired during
decades of such studies with crystal spectrometers, the IDT has
developed a conceptual design for a focussed-beam, time-of-flight
instrument for the SNS called HYSPEC (an acronym for
[hy]{.underline}brid [spec]{.underline}trometer). This Letter of Intent
is a request by the IDT for approval of HYSPEC as an instrument for the
SNS and for the allocation to HYSPEC of a beamline served by a coupled,
20 K supercritical hydrogen moderator.

# SCIENTIFIC OBJECTIVES:

HYSPEC is intended to supply users of the SNS with a platform for
studies of the low-energy dynamical properties of single crystal
samples. These samples tend to be grown specifically for such
investigations and are usually small so concentrating the incident beam
to a size that matches the sample is vital if acceptable data collection
rates are to be achieved. A further complication is that the signal of
interest is often weak because the scattering cross-section is small: a
reduced background (increased signal-to-noise ratio) is therefore
crucial for meaningful measurements. Moreover, many of the experiments
involve parametric studies extending over limited ranges of Q, and the
external parameters being magnetic or electric field, stoichiometry and
pressure and temperature - and require special environments provided by
cryostats, magnets, pressure cells, etc. Placed in the neutron beam,
such devices become additional sources of background; an important
consideration in developing a spectrometer for such studies. All of
these concerns are addressed in the design of the HYSPEC spectrometer.
Additionally, we note that polarization analysis is expected to become
increasingly important in exploring the properties of magnetic system
and that HYSPEC (unique at the SNS) will be an instrument that can be
easily configured to polarize the incident beam and analyze the
polarization of the scattered neutrons with well-tested (and very
efficient) methods.

Below we highlight a selection of problems that are currently at the
forefront of condensed matter research and that demonstrate the need for
an instrument such as HYSPEC. They are intended to be illustrative;
there are many more that - space permitting - could be mentioned.

I)  Correlated Phases in Many-electron Systems:

> 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 orbitally ordered phases in transition metal oxides such
> as the superconducting cuprates and magnetoresistive manganites.
> 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 striped liquid phases in the doped layered
> nickelates, incommensurate dynamical correlation in the cuprate
> superconductors 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~.
>
> A spectrometer, optimized for studies of the short- and long-range
> static and dynamic correlations in single crystals should be designed
> to have both a small elastic and 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
> will be evident, the proposed HYSPEC spectrometer is designed to both
> provide superior performance and to address these concerns.

II) Nanomagnetism:

> Molecular magnets exhibit spectacular physical properties (such as
> macroscopic tunneling and quantum coherence) and some of these may be
> exploited in emerging technologies ranging from spin valves to quantum
> computing and photonic switches. The more recently synthesized
> molecular magnets are composed of molecules, containing a number of 3d
> or 4f magnetic ions connected by organic or inorganic linking atoms.
> These systems are ideal for studying the transition between atomic and
> nano-scale magnetic phenomena, since molecules incorporating as few as
> two, and, to date, as many as 30 magnetic ions (Mo~72~Fe~30~) have
> been synthesized. In addition, these structures make it possible to
> explore a range of associated magnetic phenomena from S =1/2 quantum
> spins (e.g. Cu, V ions) to essentially classical spins (such as Fe^3+^
> (S = 5/2) and Tb^3+^ (J = 6) ions). A critical advantage of molecular
> magnets over conventional nanosized magnetic particles is that single
> crystals composed of identical molecular units can be grown for
> detailed neutron scattering studies. The polarization analysis
> capability of HYSPEC will be an invaluable tool for the study of these
> systems because it is essential to establish the origin (magnetic or
> nuclear) of the large number of peaks observed in the existing studies
> of these materials by elastic or inelastic neutron scattering
> techniques. Moreover, these systems can only be grown in limited sizes
> and the focussing capabilities of HYSPEC will maximize the incident
> flux and most likely be the determining factor for definitive
> experiments.

III) Quantum Critical Points:

> 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 /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. The ability to
> utilize extreme sample environments on HYSPEC will be especially
> important in investigating quantum phase transitions. Also, the
> focussing properties of HYSPEC will be vitally important because of
> limited sample sizes and volumes.

IV) Low Dimensional Magnetism:

> Amazing progress has been made in the field of low-dimensional quantum
> 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.

V)  Anomalous Phonon Behavior in Functional Materials:

> 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 PMN 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.

# THE HYSPEC SPECTROMETER

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 (5-100 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 (E/E 0.03-
0.10; Q/Q 0.01-0.03), (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 Fig. 1. The instrument parameters are summarized in
Table I.

![](media/image1.jpeg){width="4.8484251968503935in"
height="2.9429133858267718in"}

# 

# 

# Primary spectrometer (Monochromator)

As is evident in the figure, the primary (monochromating) section of the
instrument is envisioned as consisting of a 15-25 meter long guide with
a center section composed of 40 mm wide by 150 mm high,
supermirror-coated, pseudo-curved modules and with 40 mm wide expander
sections at each end. Placed at intervals along the guide would be three
disk choppers; two -- the T~0~ and frame-overlap choppers - rotating at
either the source frequency or a sub-multiple and the third - a
counter-rotating disk chopper pair

## Table I: Instrument Parameters

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

  Incident energy                5-100 meV

  Energy resolution              0.03\<E/E\<0.10 (for elastic scattering)
                                 depending on neutron energy and rotation
                                 rates of choppers

  Q resolution                   Q/Q \~ .01 - .03

  Primary flight path            Curved guide with expander and
                                 compressor sections 15-25 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 chopper. Maximum rotation rate 60
  chopper                        Hz

  Flux focussing 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^
  focussed)                      

  Detectors                      275 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
  ------------------------------ ----------------------------------------

\- rotating at integral multiples of the source frequency. At the
guide's downstream end we plan to place a rotating drum shield
containing a vertical-focussing crystal, a beam stop, a vertically
tapered guide (downstream of the crystal), a Fermi chopper and a Soller
collimator. Attached to the shield - and moving with it -- would be a
conventional sample axis with a 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 focussing the
beam at the sample position.

Each chopper has a unique part to play in monochromating the 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) contamination
is removed. Also, its rotation rate can be reduced to block alternate
source pulses in cases where the scattered energy spectrum is so broad
that spectral overlap becomes a problem. When the instrument is operated
in a low-resolution, high-data-collection- rate mode, 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 major factor in
determining the energy resolution of the analyzing section. In 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 monochromating crystal, we propose using (for non-polarized
applications at incident neutron energies of 5 meV and higher)
individual pyrolytic graphite (PG) plates attached to a segmented
GMI-type holder. This arrangement provides optimal vertical focussing.
Because a relatively broad horizontal mosaic (probably 1.0 ^o^) will be
needed for optimum performance, our present thinking is 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 while keeping the vertical
mosaic (and thus the vertical focussing properties of the crystal)
unchanged. At incident neutron energies below 5 meV, where the very high
monochromator resolution introduced by the PG crystal in a near
backscattering geometry might have an unacceptable impact on the
intensity, we envision substituting an equivalent crystal composed of
fanned plates of fluorinated synthetic mica.

**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 275
one-dimensional, position-sensitive, tube-type ^3^He detectors. A radial
collimator interposed between the sample and detectors would restrict
their horizontal field of view to the sample area alone. Individual
horizontal and vertical pixel resolutions are envisioned as being 20
minutes of arc. Additionally, the array would span a 60 degree arc
horizontally and have a vertical acceptance of plus and minus 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.

**Polarization Analysis**

When a need for polarization analysis arises, the PG crystal would
either be replaced by a Heusler alloy crystal or, (at incident neutron
energies \< 15 meV) a high efficiency, beam-bender type polarizer would
be positioned downstream. Additionally, one or more beam bender type
polarizers with high vertical angular acceptance would be placed in the
flight path between the sample and the detector bank to serve as
polarization analyzers for E~f~ \< 15 meV. Use of beam benders for
neutron polarization is a well established method for producing
polarized beams of low energy neutrons. They are commercially available
and either in use or planned at NIST, ILL and other state of the art
facilities. The use of well-established, highly efficient methods of
both incident neutron polarization and analysis of scattered neutron
polarization is a unique and especially attractive feature of HYSPEC. It
is not duplicated by any other currently planned SNS instrument.

### Sample Area

Also of note is the convenience with which specialized sample
environments can be utilized. Because collimation upstream and
downstream of the sample will restrict the horizontal field of view of
the detectors to the sample area alone, the sample axis will not have to
be part of the instrument vacuum system as is the case in other planned
inelastic instruments. Thus we expect to be able to employ conventional
cryostats, magnets, furnaces, pressure cells, etc. without creating
sample environment related background problems. This is another unique
feature of HYSPEC.

### 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 focussing properties of curved crystals to concentrate the
monochromatic flux on small samples.

To quantify the advantage of the HYSPEC concept in this respect, a
number of Monte- Carlo-based, flux-on-sample simulations were made
using, for comparison, an optimized version of the instrument in which
the HYSPEC chopper-crystal monochromating section is replaced by a more
conventional, multi-chopper, IN-5 type monochromator (see Fig 2). All
simulations were made with the LANL NISP Monte Carlo program. To assure
they were as balanced as possible, both instruments were assumed to be
supplied with neutrons by identical, coupled, 20 K, supercritical H~2~
SNS moderators and both were given primary and secondary flight paths of
the same length and guides of the same width (4 cm). The heights of the
various guide sections and (for HYSPEC) the curvature of the

crystal were then iteratively adjusted to give the maximum monochromatic
flux on a 2 cm high sample. As is evident in Fig. 3, despite the finite
reflectivity of the PG crystal, its superior focussing properties
concentrate the monochromatic flux on small samples much more
effectively. For the moderate resolution, (small) single crystal sample
studies for which it is planned, the HYSPEC approach is markedly
superior.

![](media/image2.jpeg){width="5.81875in" height="4.2444444444444445in"}

![](media/image3.pct)

**MODERATOR CHOICE:**

Monte Carlo simulations have also shown that to perform optimally over
the incident neutron energy range of interest (5-100 meV), a
spectrometer of this type needs to be located on a beamline served by a
coupled, 20 K, supercritical H~2~ moderator. Our first choice would be
beam Line #13. Because optimum performance requires that the
monochromator and analyzer energy resolutions be reasonably well
matched, it is highly desirable that the 20-25 m long monochromating
section end 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 significant

reduction of monochromatic flux at the sample position.

**ADDITIONAL ADVANTAGES OF THE HYSPEC CONCEPT:**

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

Incident neutron energy selection would be primarily by time-of-flight
as would

analysis of scattered neutron energies. Thus full advantage is taken of
the pulsed

nature of the 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 easily accessible to
    investigation.

-   Depending on the type of measurement, the spectrometer could be
    operated in either a wide-angular-acceptance or Q-selective mode.

-   Apart from its focussing properties, the crystal also has the effect
    of substantially reducing the (source produced) spectral asymmetry
    of the beam incident on the sample.

-   A relatively wide primary beam 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 (5E~n~100
    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.

-   Changing the collimation of the incident monochromatic beam or the
    angular acceptance at the analyzer (or both) is all that is needed
    to vary the longitudinal Q-resolution.

-   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.

**FUTURE CONSIDERATIONS:**

Yet to be addressed in detail are two design issues. The first relates
to keeping the background to a minimum: the beam stop will either have
to be fitted into a confined space in the shielding drum or mounted at
the end of a "get-lost" pipe, (the latter would restrict the swing of
the analyzer at the highest incident neutron energies). 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
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.

There is also the earlier-mentioned limitation on location that the
Committee will need to take into consideration: Because the sample axis
is significantly offset from the primary beam, the combined drum shield,
analyzer and associated analyzer shielding will require a
more-than-normal amount of space on the experimental floor and place
significant constraints on the choice of beamline.

> Members of the IDT and their Institutional Affiliations
>
> Igor Zaliznyak, co-PI BNL
>
> S. M. Shapiro, co-PI BNL
>
> G. Shirane BNL
>
> J. Tranquada BNL
>
> L. Passell (retired) BNL
>
> D. Abernathy SNS
>
> L. Daemon Los Alamos
>
> M. Greven Stanford
>
> B. Gaulin McMaster
>
> V. Kiryukhin Rutgers
>
> Y. Lee MIT
>
> S. Nagler ORNL
>
> R. Osborn ANL
>
> J. Rhyne U. Missouri
>
> C. Stassis Ames Lab/Iowa St.
>
> A. Zheludev ORNL
>
> **Tentative Cost Estimates**

  ------------------------------- ---------------------------------------
  **HYSPEC COSTS**                **k\$**

                                  

  CHOPPERS                        1120

  SHUTTERS                        120

  SHIELDING                       2350

  SUPERMIRROR GUIDES              500

  MONOCHROMATORS                  250

  COLLIMATORS                     100

  SAMPLE GONIOMETER               50

  BEAM MONITORS                   15

  EXTERNAL BUILDING\*             1500

  DETECTORS                       700

  DETECTOR STRUCTURE              685

  POLAR. ANALYSIS                 480

  DATA COLLECTION                 200

  ANCILLARY EQUIPMENT             50

  **TOTAL (CAPITAL)**             8120

                                  

  **LABOR**                       3000

                                  

  **TOTAL**                       11120

  \*if necessary                  
  ------------------------------- ---------------------------------------