Beam loss detection by scintillation monitor

Miura, Akihiko ; Maruta, Tomofumi; Sako, Hiroyuki   ; Hasegawa, Kazuo; Ouchi, Nobuo ; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*

Ar-CO gas proportional beam loss monitors (BLMs) have measured the beam loss through operations, but they are also sensitive to background noise of X-ray emitted from RF cavities. For the future energy upgrade of J-PARC linac, because 21 RF cavities are additionally installed in the beam line, the background noise would be serious problem. We employed the scintillation monitors to measure the beam loss which would bring more accurate beam loss measurements with suppression of X-ray noise. As the measurement results, a good signal to noise ratio is observed for the scintillation monitor with quite low sensitivity to the background X-ray. This paper describes the beam loss measurement system using a scintillation monitor.