2011 Particle Accelerator Conference - List of Authors (Davidsaver, M.A.)

Paper	Title	Page
WEP178	Electromagnetic Field Measurement of Fundamental and Higher-order Modes for 7-cell Cavity of PETRA-II	1822
	Y. Kawashima, A. Blednykh, J. Cupolo, M.A. Davidsaver, B. Holub, H. Ma, J. Oliva, J. Rose, R. Sikora, M. Yeddulla BNL, Upton, Long Island, New York, USA
	The booster synchrotron for NSLS-II will include a 7-cell PETRA cavity, which was manufactured for the PETRA-II project at DESY. The cavity fundamental frequency operates at 500 MHz. In order to verify the impedances of the fundamental and higher-order modes (HOM) which were calculated by computer code, we measured the magnitude of the electromagnetic field of the fundamental acceleration mode and HOM’s, using the bead-pull method. To keep the cavity body temperature constant, we used a chiller system to supply cooling water at 20 degrees C. The bead-pull measurement was automated with a computer. We encountered some issues during the measurement process due to the difficulty in measuring the electromagnetic field magnitude in a multi-cell cavity as compared to a single-cell cavity. We describe the apparatus for the field measurement and the obtained results.

Paper

Title

Page

Electromagnetic Field Measurement of Fundamental and Higher-order Modes for 7-cell Cavity of PETRA-II

1822

Y. Kawashima, A. Blednykh, J. Cupolo, M.A. Davidsaver, B. Holub, H. Ma, J. Oliva, J. Rose, R. Sikora, M. Yeddulla
BNL, Upton, Long Island, New York, USA

The booster synchrotron for NSLS-II will include a 7-cell PETRA cavity, which was manufactured for the PETRA-II project at DESY. The cavity fundamental frequency operates at 500 MHz. In order to verify the impedances of the fundamental and higher-order modes (HOM) which were calculated by computer code, we measured the magnitude of the electromagnetic field of the fundamental acceleration mode and HOM’s, using the bead-pull method. To keep the cavity body temperature constant, we used a chiller system to supply cooling water at 20 degrees C. The bead-pull measurement was automated with a computer. We encountered some issues during the measurement process due to the difficulty in measuring the electromagnetic field magnitude in a multi-cell cavity as compared to a single-cell cavity. We describe the apparatus for the field measurement and the obtained results.