Abstracts Brochure - CERN

MOPCH — Poster Session 26-Jun-06 16:00 - 18:00
Stochastic Cooling for the HESR at the GSI-FAIR Complex
The High-Energy Storage Ring (HESR) of the
future International Facility for Antiproton
and Ion Research (FAIR) at the GSI in Darmstadt
is planned as an anti-proton cooler ring
H. Stockhorst, B. Lorentz, R. Maier, D. Prasuhn (FZJ) T. Katayama
(CNS)
in the momentum range from 1.5 to 15 GeV/c. An important and challenging feature of the new facility is the combination
of phase space cooled beams with internal targets. The required beam parameters and intensities are prepared
in two operation modes: the high luminosity mode with beam intensities up to 10 11 and the high reso-lution mode
with 10 10 anti-protons cooled down to a relative momentum spread of only a few 10-5. In addition to electron cooling,
transverse and longitudinal stochastic cooling are envisaged to accomplish these goals. It is shown how the great
benefit of the stochastic cooling system to adjust the cooling force in all phase planes independently is utilized to
achieve the requested beam spot and the high momentum resolution at the internal target within reasonable cooling
down times for both HESR modes even in the presence of intra-beam scattering. A numerical and analytical approach
to the Fokker-Planck equation for longitudinal filter cooling has been carried out.
Quasi-adiabatic Transition Crossing in the Hybrid Synchrotron
Non-adiabatic features around the transition
energy are well-known to be one of most im- Y. Shimosaki, K. Takayama, K. Torikai (KEK)
portant beam physics issues in most of circular
hadron accelerators. A novel technique to avoid them by the adiabatic motion, a quasi-adiabatic focusingfree
transition crossing (QAFFTC), was proposed. In a longitudinally separated function-type accelerator*, in which
particles are confined by an rf voltage or burrier voltages and accelerated by a step voltage, the confinement voltage
can be arbitrarily manipulated as long as the particles do not diffuse, while a strict acceleration voltage is necessary for
the orbit of a charged particle to be balanced in the radial direction. The introduction of QAFFTC is most suitable for
the longitudinally separated function-type accelerator. This new method was examined in this type of accelerator**,
both theoretically and experimentally. This was a first and significant application of the hybrid synchrotron. The
results will be presented.
*K. Takayama and J. Kishiro, Nucl. Inst. Meth. A 451, 304 (2000).**K. Takayama et al. Phys. Rev. Lett. 94, 144801
(2005).
Ion Cooler Storage Ring, S-LSR
Ion cooler and storage ring, S-LSR has been
constructed. Its beam commissioning has
been successfully performed since October,
2005 and electron beam cooling for 7 MeV
proton beam has been performed with both
flat and hollow spatial distributions. Effect
A. Noda, S. Fujimoto, M. Ikegami, T. Shirai, H. Souda, M. Tanabe,
H. Tongu (Kyoto ICR) H. Fadil, M. Grieser (MPI-K) T. Fujimoto, S.I.
Iwata, S. Shibuya (AEC) I.N. Meshkov, I.A. Seleznev, A.V. Smirnov,
E. Syresin (JINR) K. Noda (NIRS)
of relative velocity sweep between electron and ion beams on the cooling time* has been confirmed. Based on the
success to create the peaks in the energy spectrum of laser-produced ions, injection of laser-produced ions into S-
LSR after rotation in the longitudinal phase space by an RF cavity synchronized to the pulse laser is under planning
in order to apply electron cooling for such real laser produced hot ions. Three dimensional laser cooling satisfying
the condition of ’tapered cooling’ is also under investigation. 24Mg+ ions are to be laser-cooled only in the ’Wien
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