2011 Particle Accelerator Conference - List of Authors (Morrison, L.H.)

Paper	Title	Page
TUP283	Inductively Coupled, Compact HOM Damper for the Advanced Photon Source	1358
	G.J. Waldschmidt, D. Horan, L.H. Morrison ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357 The Advanced Photon Source requires damping of higher-order modes in the storage ring rf cavities in order to prevent beam instability at beam currents in excess of 100 mA proposed for the APS Upgrade. Due to constraints imposed by available space and by existing 35-mm pick-up ports on the cavity, a compact design has been analyzed with a quarter-wave rejection filter of the fundamental mode. Separate broadband, low-frequency and high-frequency dampers are utilized to span the frequency range from 500 MHz to 1500 MHz. The dampers have been designed to reject the fundamental cavity mode, couple strongly to HOM’s, utilize an external rf load, minimize the overall size, and incorporate rf diagnostics. In addition, the mechanical design has been optimized to simplify construction, improve mechanical stability, and reduce thermally induced stresses.

Paper

Title

Page

Inductively Coupled, Compact HOM Damper for the Advanced Photon Source

1358

G.J. Waldschmidt, D. Horan, L.H. Morrison
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357
The Advanced Photon Source requires damping of higher-order modes in the storage ring rf cavities in order to prevent beam instability at beam currents in excess of 100 mA proposed for the APS Upgrade. Due to constraints imposed by available space and by existing 35-mm pick-up ports on the cavity, a compact design has been analyzed with a quarter-wave rejection filter of the fundamental mode. Separate broadband, low-frequency and high-frequency dampers are utilized to span the frequency range from 500 MHz to 1500 MHz. The dampers have been designed to reject the fundamental cavity mode, couple strongly to HOM’s, utilize an external rf load, minimize the overall size, and incorporate rf diagnostics. In addition, the mechanical design has been optimized to simplify construction, improve mechanical stability, and reduce thermally induced stresses.