DIPAC2011 - List of Authors (Takai, R.)

Paper	Title	Page
TUPD03	Beam Profile Measurement during Top-up Injection with a Pulsed Sextupole Magnet	305
	R. Takai, K. Harada, T. Honda, Y. Kobayashi, S. Nagahashi, N. Nakamura, T. Obina, A. Ueda KEK, Ibaraki, Japan H. Takaki ISSP/SRL, Chiba, Japan
	A beam injection scheme using a pulsed multipole magnet is suitable for the top-up injection because a disturbance to the stored beam is much smaller than that of the conventional scheme using several kicker magnets. At the Photon Factory storage ring, the top-up injection with a pulsed sextupole magnet (PSM) has been used for the user operation since January 2011. In order to ascertain the effect of the PSM injection, we measured turn-by-turn stored beam profiles following the injection kick by using a fast-gated camera. As a result, it was demonstrated that the PSM injection dramatically decreases not only the coherent dipole oscillation but also the beam profile modulation, as expected from the beam tracking simulation.

TUPD73	Fast Orbit Stabilization System for Tandem APPLE-II Undulators at the KEK-PF	479
	T. Obina, K. Harada, R. Takai KEK, Ibaraki, Japan
	A rapid-polarization switching source has been developed in the KEK-PF 2.5-GeV electron storage ring. The source consists of two tandem APPLE-II type elliptically polarizing undulators (EPU) and five fast kicker magnets. The kicker magnets produce a local bump orbit at the frequency up to 100 Hz. Amplitude and phase of these magnets must be tuned precisely in order to minimize the leakage of residual orbit outside of the kicker bump. A fast orbit stabilization system which consists of ADC/FPGA/DAC are also developed to reduce the remaining orbit fluctuations in vertical and horizontal planes. In this paper, design and the preliminary result of the fast orbit compensation system is presented.

Paper

Title

Page

Beam Profile Measurement during Top-up Injection with a Pulsed Sextupole Magnet

305

R. Takai, K. Harada, T. Honda, Y. Kobayashi, S. Nagahashi, N. Nakamura, T. Obina, A. Ueda
KEK, Ibaraki, Japan
H. Takaki
ISSP/SRL, Chiba, Japan

A beam injection scheme using a pulsed multipole magnet is suitable for the top-up injection because a disturbance to the stored beam is much smaller than that of the conventional scheme using several kicker magnets. At the Photon Factory storage ring, the top-up injection with a pulsed sextupole magnet (PSM) has been used for the user operation since January 2011. In order to ascertain the effect of the PSM injection, we measured turn-by-turn stored beam profiles following the injection kick by using a fast-gated camera. As a result, it was demonstrated that the PSM injection dramatically decreases not only the coherent dipole oscillation but also the beam profile modulation, as expected from the beam tracking simulation.

TUPD73

Fast Orbit Stabilization System for Tandem APPLE-II Undulators at the KEK-PF

479

T. Obina, K. Harada, R. Takai
KEK, Ibaraki, Japan

A rapid-polarization switching source has been developed in the KEK-PF 2.5-GeV electron storage ring. The source consists of two tandem APPLE-II type elliptically polarizing undulators (EPU) and five fast kicker magnets. The kicker magnets produce a local bump orbit at the frequency up to 100 Hz. Amplitude and phase of these magnets must be tuned precisely in order to minimize the leakage of residual orbit outside of the kicker bump. A fast orbit stabilization system which consists of ADC/FPGA/DAC are also developed to reduce the remaining orbit fluctuations in vertical and horizontal planes. In this paper, design and the preliminary result of the fast orbit compensation system is presented.