Abstracts Brochure - CERN

THPCH053
THPCH054
THPCH055
THPCH056
29-Jun-06 16:00 - 18:00 THPCH — Poster Session
Numerical and Experimental Study of Cooling-stacking Injection in HIMAC Synchrotron
T. Uesugi (KEK) I.N. Meshkov, E. Syresin (JINR) K. Noda (NIRS) S.
Shibuya (AEC)
402
The cooling-stacking injection at the HIMAC
synchrotron was used to increase the intensity
of Ar 18+ ion beam. The beam stacking
was realized in a horizontal free phase-space,
which was created by the HIMAC electron cooler. The stack intensity of (1.5∼2.5)·10 9 ppp was accumulated at an
injection intensity of (0.3∼1.0)e9. The stack intensity was limitted by the ion lifetime. A peculiarity of present coolingstacking
experiments is related to lifetime difference by a factor of 2∼3 of the stack and injected ions. The lifetime
of stack ions is determined by vacuum pressure. The new injected ions were slowly lost at multiple scattering on
residual gas atoms at diffusion heating in the vertical direction caused by the acceptance of 30pi-mm-mrad and a
reduction of cooling force at large betatron amplitudes. The results of numerical simulations and experimental study
of cooling-stacking injection on the HIMAC synchrotron are presented.
Simpsons with Wake Field Effects
Y. Shobuda, F. Noda (JAEA/J-PARC) Y.H. Chin, K. Takata (KEK) S.
Machida (CCLRC/RAL/ASTeC)
Simpsons, which is originally developed by
S. Machida, is the program which calculates
the space charge effect to the beam in the
ring. The wake field effect to the beam is
also installed in this program, because the beam instability not only due to the space charge effect, but also due to the
wake field effect is the important issue. The results of the simulation in J-PARC case are also represented.
Simulations on Fast-ion Instabilities in the ILC Damping Rings
We report results of simulations on the fast-
E.-S. Kim (PAL) K. Ohmi (KEK)
ion instabilities at the baseline and alternative
damping rings for the ILC-RDR. We will
investigate effects of the bunch filling patterns, low bunch charge and lattices on the fast-ion instabilities in the
damping rings. The simulations will guide us to know how to minimize the effects of the instabilities in the damping
rings.
The Effect of Periodic Magnetic Field on Budker-Chirikov Instability
The two-beams electron - ion system consists
Y. Golub (MRTI RAS)
of a nonrelativistic ion beam propagating coaxially
with a high-current relativistic electron
beam in a both longitudinal homogeneous and in a periodic magnetic fields. The periodic magnetic field has a
spatial period as in undulator. The effect of the periodic magnetic field on instability Budker-Chirikov (BCI) in the
system is investigated by the method of a numerical simulation in terms of the kinetic description of both beams. The
investigations are development of investigations in */**. Is shown, when the periodic magnetic field results in the
decreasing of an increment of instability Budker-Chirikov and the increasing of length of propagation of a electron
beam.