Abstracts Brochure - CERN

THPLS109
THPLS110
THPLS111
THPLS112
29-Jun-06 16:00 - 18:00 THPLS — Poster Session
Measurements and Diagnostics on the MAX Recirculator
The MAX Recirculator is a unique accelera-
M. Brandin (MAX-lab)
tor, a two-pass linac at 500 MeV, that operates
as injector for three storage rings. Here are
presented some discussions on measurments of beam parameters such as emittance, energy spread, and bunch length.
We describe what measurements are done, by wich methods, results, and how they can be improved. Also, we make
an analysis of What methods and hardware are needed to perform the measurements that can’t be done with the
equipment in place today.
Injection Scheme for TPS Storage Ring
Taiwan Photon Source(TPS), a 3∼3.3 GeV
M.-H. Wang, H.-P. Chang, C.-C. Kuo, G.-H. Luo (NSRRC)
synchrotron light source with full energy injection
is proposed to be built at NSRRC in
Taiwan. In this paper we report the design of injection scheme for TPS. The space allocation of the injection components,
the bumper design, the aperture consideration and the injection dynamics of injected and stored beam will
all be discussed. The particle tracking of first few turns of injection is performed to evaluate the injection efficiency
with the errors caused by the time jitter and amplitude stability of injection kickers. The issue of constant current
operation will be also addressed.
Beam Loading Measurement and its Application to the Harmonic RF Control of the APS
PAR
C. Yao, E.E. Cherbak, N.P. Di Monte, A. Grelick, T. Smith, B.X. Yang
(ANL)
478
The particle accumulator ring (PAR) has dual
rf systems: a CW mode fundamental rf system
(RF1) operating at 9.77 MHz that accumulates
multiple linac pulses into a 0.8-ns
bunch, and a 12th harmonic rf (RF12) that compresses the bunch length further to 0.34 ns for injection into the booster.
The RF12 capture process is critical for optimal performance of the PAR. We investigated the effects of beam loading
during the RF12 capture and bunch length compression process with both spectrum analysis and streak camera
imaging. Based on these observations, a new timing scheme for the RF12 tuner and power control was implemented,
which has substantially improved the performance of the PAR. We report our observation, the new timing scheme,
and beam parameters after optimization.
Electron Multipacting Observation and Simulation in the APS PAR
The particle accumulator ring (PAR) has both
C. Yao, Y.-C. Chae (ANL)
fundamental and 12th harmonic rf systems.
Gap voltage fluctuations were experienced
after vacuum work was performed on the PAR during a maintenance period. This has caused intermittent beam
instability and prevented us from running the PAR fundamental rf system at normal power level. Our investigation
has concluded that the problem was caused by electron multipacting in the center vacuum chamber of the cavity. We
were able to suppress the multipacting by applying a solenoid field in the suspected region. Computer simulation