JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Satou, K. AU - Igarashi, S. AU - Sato, Y. ED - Forck, Peter ED - Wawrzyniak, Adriana ED - Schaa, Volker R.W. ED - Kowalski, Grzegorz W. ED - Cudek, Agnieszka (SOLARIS, Kraków TI - Merits of Pulse Mode Operation of Residual Gas Ionization Profile Monitor for J-PARC Main Ring J2 - Proc. of IBIC2022, Kraków, Poland, 11-15 September 2022 CY - Kraków, Poland T2 - International Beam Instrumentation Conference T3 - 11 LA - english AB - The measurement accuracy of the ionization profile monitor (IPM) of J-PARC main ring (MR) depends on the flatness and stability of the gain of the position-sensitive microchannel plate (MCP). The flatness of the MCP deteriorates after long-term operation; the gain of the central area selectively decreases as the integrated output charge increases. The beam-based calibration, where the local bump shifts the beam and the reconstructing beam profiles determine the gain distribution, is used to calibrate the flatness. The immediate gain drop occurs when the output current from the MCP becomes comparable to the bias current is problematic. This gain drop depends on the bias voltage and the output current; thus, it is difficult to calibrate. A pulsed HV module of 30 kV, which collects ionized electrons and ions, was installed to solve these problems. The pulse mode operation can modulate the averaged output current from the MCP to improve gain stability. Profiles of the intense beam up to 3.3·10¹³ ppb were measured and compared with those measured by destructive profile monitors in beam transport lines 3’50 BT, and the Abort line. Estimated emittances were consistent at ±20%. PB - JACoW Publishing CP - Geneva, Switzerland SP - 434 EP - 437 KW - electron KW - operation KW - injection KW - emittance KW - ECR DA - 2022/12 PY - 2022 SN - 2673-5350 SN - 978-3-95450-241-7 DO - doi:10.18429/JACoW-IBIC2022-WEP21 UR - https://jacow.org/ibic2022/papers/wep21.pdf ER -