ACTIVITIES AND FUTURE PLANS AT LNF
M. Preger
INFN, Laboratori Nazionali di Frascati, C.P. 13, 00044 Frascati (Roma), Italy

Abstract
The Frascati National Laboratory (LNF) is the largest
unit of the National Institute for Nuclear Physics (INFN).
It hosts the main high energy accelerator facilities in Italy
and is presently running DAΦNE [1], an electron-positron
collider for the production of K mesons from the decay ofthe Φ resonance at 1.02 GeV c.m. INFN is going to present its three years plan to the Italian Government next
May, and decisions on future programs are being discussed
by the Scientific Committees of the Institute. After ashort presentation of the main activities under way in thelab, I concentrate on the discussion about future developments in the accelerator field on site and participation to
the realization of large facilities abroad in the frameworkof international collaborations.

1 ACTIVITIES AT LNF
LNF is the largest National Laboratory of INFN, witha staff of 128 between physicists and engineers, 156 technicians and 33 administrative employees. About 100
physicists from universities and INFN sections in Italy
are also routinely participating to the experiments in thelab. The research personnel is organized in two groups,
the Accelerator Division and the Research Division. It
supports activities and collaborations in all the five scientific lines of the institute:• particle physics with accelerators (Scientific Committee 1, SC1)
• particle physics without accelerators (SC2)• nuclear physics (SC3)• theoretical physics (SC4)• technological research (SC5)
LNF presently runs two important facilities on site:
DAΦNE [1], an electron-positron collider with a center ofmass energy of 1.02 GeV, which produces a large rate ofkaons from the decay of the Φ resonance, and NAUTILUS, a cryogenic gravitational wave detector. However,
an important fraction of the activity of its scientific staff
takes place as collaborations at experiments performed atother laboratories in Italy or abroad.
SC1 activities can be subdivided into two main categories. The first one are general purpose experiments at the"high energy frontier" in operation or under construction,
like CDFII at Fermilab and ATLAS at LHC, the second
are the experiments on the "statistical frontier", mainly on
CP violation, like KLOE [2] at DAΦNE and BaBar at
SLAC. While CDFII, ATLAS and BaBar are international

collaborations, KLOE is carried on mostly by physicists
from LNF and italian universities and INFN sections. It
consists of a large cylindrical detector (5 m length by 5 m
diameter) embedded into a superconducting solenoid, andits goal is the study of CP violation in kaonic decays ofthe Φ resonance. KLOE is presently running on one of
the two interaction regions of DAΦNE.
The main subjects explored in SC2 are the study ofneutrino oscillations in natural or artificial beams, theresearch for gravitational waves and astroparticle physics.
Most experiments with large detectors (ICARUS, LVD,
MACRO, OPERA) are performed at another importantNational Laboratory of INFN, the underground facility atGran Sasso. In the field of gravitational waves the NAUTILUS antenna at LNF is running continuously at extremely low temperature (less than 0.1 K) in coincidencewith another antenna at CERN (EXPLORER). LNF
physicists also participate to a 3 km long laser interferometer (VIRGO) under construction near Pisa. Conserning astroparticles the PAMELA project is active in thefield of antimatter and cosmic rays research based on particle detectors onboard a satellite expected to be launchednext year.
The main activities on site in the field of nuclear physics are two experiments on DAΦNE. DEAR [3] is dedicated to the study of exotic atoms where the kaons produced by electron-positron interactions are captured in theelectronic shells. DEAR is presently taking data on theother interaction region of DAΦNE and is expected to run
until summer 2002. FINUDA [4] is a large magnetic detector to be installed at DEAR's place, and will study thephysics of hypernuclei, running together with KLOE.
Several experiments are under way at laboratories abroad,such as AIACE at TJNAF, DIRAC at CERN, GRAAL at
ESRF and HERMES at DESY. LNF collaborates also at
the ELFE project, a high duty cycle european electron
facility for nuclear physics.
The theory group of LNF consists of ≈15 people working in the fields of strongly correlated electrons, condensed
matter physics, non-perturbative aspects of gauge theories
in gravitation, superstrings, QCD, CP violation and particle phenomenology, bozonization in many bodies.
Finally, activities in SC5 include synchrotron radiation
research on three high intensity beam lines from DAΦNE
in the infrared, UV and soft X-rays, studies on accelerator
components, detectors and cold fusion.
Information on LNF activities can be found on the site
http://www.lnf.infn.it.

2 ACCELERATOR ACTIVITIES
2.1 DAΦNE
The main activity at LNF in the accelerator field is
DAΦNE. The status of the machine is extensively described in another paper at this Conference [1]. Obviously, the major effort of the Accelerator Division is in
the direction of improving the performance of the collider
in order to approach as far as possible its design luminosity of 5x1032 cm-2s-1. In terms of integrated luminosity,
DAΦNE is presently delivering ≈1 pb-1 per day, to becompared to the upper limit of ≈40 pb-1 which could bedelivered by running at full design luminosity and fullefficiency.
The main goal of the KLOE experiment is the measurement of the CP-violating parameter Re(ε'/ε). This
study is presently being carried out also with extracted
proton beams at Fermilab (KTeV) and CERN (NA31 andNA48). Recent results from both collaborations indicatethat this parameter is in the range 1÷2x10-3. KLOE willmeasure Re(ε'/ε) starting from a much cleaner initial state
where KSKL are produced in pairs from the Φ decay(tagged kaons) with a totally different systematics.

Figure 1: A typical event in the KLOE detector: the Φ
decays in a Ks inside the vacuum chamber and a Kl in thedetector; then the Ks decays into π+π--, the Kl into π+e-ν.
KLOE can measure Re(ε'/ε) with an uncertainty of
10-3 with 200÷300 pb-1. A result from KLOE is necessary
to confirm the value found by the other two experimentswith a different technique. Moreover, KLOE can alsomeasure Im(ε'/ε), which will contribute significantly tothe understanding of CP violation.

The plan of LNF, supported by its Scientific Committee, is to deliver at least 200 pb-1 to KLOE during thisyear. In addition, machine time will be allocated to DEAR
in order to check if the signal-to-background ratio is highenough to perform the experiment: if this turns out to bepossible, the plan is to deliver a fraction of the required
integrated luminosity this year, and to complete the experiment within summer 2002, in order to leave place for
the FINUDA detector to be installed on DAΦNE.
The installation of FINUDA will have a strong impact
on the operation of the collider. This detector exploits asolenoidal magnetic field with the same field integral as
KLOE; the compensation will be performed in the sameway, by means of two superconducting solenoids of opposite field and by rotating the permanent magnet quadrupoles [1] embedded into the interaction region vacuum
chamber. However, since it is not clear at the moment if
it will be possible to deliver luminosity to both experiments with good efficiency, two new interaction regions
are being designed which will allow the rotation of thequadrupoles around their longitudinal axis from zero to theangle needed for the compensation. In such a way it will
be possible to operate each one of the two experimentswith the other magnet switched off and to finely tune thecoupling compensation through the additional degrees of
freedom of the independent quadrupole rotation.
Two synchrotron radiation beam lines have already been
opened on DAΦNE. The first ones conveys the radiationfrom a bending magnet and is designed to deliver radiationin the IR; in the second one the radiation comes from oneof the wigglers in the electron ring and is dedicated toexperiments in the UV and soft X-ray region (such as
microlythography, microengineering etc.). Of course,
DAΦNE is mainly a collider for high energy physics, andthe emittance of its beam is large, in order to reach highluminosity, while a synchrotron radiation source shouldhave low emittance in order to improve the brilliance ofthe source. However, DAΦNE is designed to operate witha large stored current (up to 5 A in each beam) and therefore the flux of photons is very high; in addition, the machine operates with very flat beams, and its vertical emittance (which is the most interesting parameter for synchrotron radiation sources) is rather small; this opens thepossibility of realizing a large variety of experiments inbetter conditions than at other facilities. The machine candeliver synchrotron radiation during the normal operationof the collider in a parasitic mode. Otherwise, operating ina dedicated mode, the lattice can be modified to obtain asignificantly smaller emittance. All these possibilities arestill to be explored.

2.2 TESLA AND TTF
INFN is part of the international collaboration for the
study of TESLA [5], a ≈33 km long electron-positron linear collider with a center of mass energy ranging from 500
to 800 GeV based on superconducting cavities.

A Technical Design Report (TDR) is being submitted
to the Gerrman Government for evaluation. To establish
the technical feasibility of such a large facility, a test
accelerator called TTF [6] (Tesla Test Facility) has beenrealized and is now in operation. One of the mostoutstanding results from TTF is the operation of a freeelectron laser in the self amplified mode (SASE FEL) [7].
The contribution of LNF to TTF is mainly in the field of
beam diagnostics based on optical transition radiation tomeasure beam position, profile, energy spread and emittance; a gated intensified camera is used to follow thebeam parameters evolution along the 1 ms macropulse.
The bunch length is also measured using radiation originated by coherent diffraction.
LNF has also produced the cost estimate for the
TESLA damping rings to be included in the TDR. The
rings are required to reduce the emittance of the beams inorder to reach high luminosity. They operate at 5 GeV andare 17 km long in order to damp the long TESLA macropulse; the energy loss required to obtain the short damping time of 28 ms is obtained by means of ≈300 m of
wigglers at 1.5 T or 1.8 T depending on which solution
will be adopted between the permanent magnet or conventional electromagnetic.

2.3 CLIC AND CTF3
The LNF Accelerator Division is also taking part in the
R&D program towards the construction of CLIC [8], the
CERN e+e- Linear Collider project. The design of CLIC isbased on the two beams acceleration concept, where ahigh energy and low current primary beam is accelerated
in a room temperature high gradient structure at high frequency (30 GHz) fed by the power delivered by a highcurrent and low energy drive beam in a decelerating structure. This scheme offers the advantage of a large energy
gain per unit length, and the CLIC design foresees a center of mass energy of up to 5 TeV with a total length of
the two linacs of 35 Km.
As in the case of TESLA, a test facility is necessary todemonstrate the technical feasibility of this accelerating
technique; first steps (CTF1-CTF2) have already beenrealized, demonstrating the acceleration of the drive beam,
the deceleration and energy transfer scheme and the acceleration of the main beam. However, this was done on a
reduced scale of parameters, much higher gradients being
required to realize the energy gain necessary for CLIC.
In the CLIC design, the drive beam is accelerated in along pulse at low frequency (<1 GHz) and then compressed by a factor 32 to reach the final 30 GHz bunch
structure. The compression in time is obtained by a system of isochronous and achromatic rings where different
portions of the primary bunch train from the Linac merge
together. CTF3 [9] is the last test bench for CLIC and its
aim is to demonstrate the feasibility of the overall acceleration scheme at parameters similar to those of CLIC andof the compression system in particular.

The compression factor for CTF3 is 10 and comes froma first "delay loop" which compresses the bunches by afactor 2 and a "combiner ring" giving a compression of 5.
In the framework of the international collaboration for
CLIC, LNF foresees to take charge of the design and construction of the delay loop, combiner ring and transfer
lines for CTF3. The LNF proposal has been submitted to
INFN for evaluation and funding, and the process ofmemoranda negotiation between INFN and CERN has
been started. In the meantime LNF Accelerator Division
has completed the design of the two above mentioned
rings, which is presented in the CTF3 Conceptual Design
Report. INFN has already provided some funding to LNF
in order to prototype critical project items.
Challenging issues for these two rings are:• preservation of beam quality during compression,requiring second order chromaticity and isochronicity corrections to allow full acceptance of the energy spread of the beam accelerated by the linac• stringent requirements on the vacuum chambershape and impedance to avoid emittance degradationfrom parasitic losses and coherent synchrotron radiation effects• the realization of transverse RF deflectors both fordelay loop and combiner• the construction of an extraction kicker for the
combiner with a very flat pulse.

2.3 NEUTRINO FACTORY
Recently, a group of LNF researchers has joined the international Neutrino Factory Study Group [10], based at
CERN, whose aim is to explore the feasibility of generating an intense neutrino beam from the decay of a muon
beam, cooled and stored in a ring with very long straightsections.
The LNF contribution is mainly in the design andsimulation of a test beam to demonstrate the feasibility of
the ionization cooling scheme using low frequency RF
cavities.
A preliminary study of possible RF structures has been
already presented and requirements on beam instrumentation for the measurement of small emittance variations arebeing established.

2.3 X-FEL STUDIESThe Italian Government has included into the National
Research Plan the construction of a synchrotron radiation
source at high frequency (from far UV to X-ray) based ona Free Electron Laser in the SASE regime. As a first stepin this direction, a first funding has been decided for R&D
in the fields of accelerators, undulator magnets, beamlines
and related diagnostics, in order to establish the generalparameters for the facility and its technical feasibility. A
first proposal is being prepared as a joint venture between
various research institutes in Italy, (CNR National Research Council, ENEA National Institute for Alternative

Energy, INFN and Rome II University). LNF is proposedas the site to build a high quality preinjector for a Linac.
This accelerator will be mainly a test bench for ascheme of emittance compensation to reach a normalized
emittance below 2 mm.mrad, and charge compression forpeak currents in the order of 1 kA.
At the moment two possibilities are being discussed,
one based on superconducting cavities, which would be
mandatory if a high duty cycle system comes out to berequired by the experiments to be performed on the futurefacility, and the other one based on room temperaturecavities, which could reduce the overall cost of theaccelerator.

3 CONCLUSIONSThe present activity and future plans of LNF in the accelerator field have been described. The main effort is concentrated on DAΦNE [1], which is expected to run forhigh energy physics, nuclear physics and synchrotron
radiation experiments.
Collaborations with other institutions in Italy andabroad are under way towards the realization of highenergy electron-positron colliders, muon colliders,
neutrino factories and extremely high brilliance radiation
sources at UV and X-ray wavelengths.

REFERENCES[1] M. Preger, DAΦNE Team, "Status of DAΦNE", thisConference.
[2] The KLOE Collaboration, “KLOE: a General Purpose Detector for DAΦNE”, LNF-92/019 (IR), April
1992.
[3] The DEAR Collaboration, "DAΦNE Exotic Atom
Research" (DEAR Proposal) LNF 95/055 (IR), 1955.
[4] The FINUDA Collaboration, “FINUDA: a Detector
for Nuclear Physics at DAΦNE”, LNF-93/021 (IR),May 1993.
[5] R. Brinkmann, TESLA Collaboration, "Linear Collider Projects at DESY", EPAC'98, Stockholm, June
1998.
[6] B. Aune, TESLA Collaboration, "Results from the
DESY TESLA Test Facility". PAC'97, Vancouver,May 1997.
[7] J. Rossbach, TESLA FEL Collaboration, "TheTESLA Free Electron Laser - Concept and status",
LINAC'98, Chicago, August 1998.
[8] J.P. Delahaye et al., "CLIC, a 0.5 to 5 TeV e+eCompact Linear Collider", EPAC'98, Stockholm,
June 1998.
[9] H. Braun, "Achievements and future plans for CLIC
Test Facilities", this Conference.
[10] A Lombardi, "Status Report on Studies for Neutrino
Factories and Muon Colliders", this Conference.