Method to identify electrons emerging from elementary particle interactions by detecting Synchrotron radiation X rays.

Research Project

Project/Area Number	60460022
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	核・宇宙線・素粒子
Research Institution	National Laboratory for High Energy Physics, Niigata University
Principal Investigator	ABE Kazuo National Laboratory for High Energy Physics, その他, 助教授 (80167931)
Co-Investigator(Kenkyū-buntansha)	MIYANO Kazumasa Niigata University, 理学部, 助教授 (10011529) SAKAI Yoshihide National Laboratory for High Energy Physics, トリスタン計画推進部衝突ビーム測定器研究系, 助手 (90170571) MAKI Akihiro National Laboratory for High Energy Physics, 物理研究系, 助教授 (40044755)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥4,200,000 (Direct Cost: ¥4,200,000) Fiscal Year 1986: ¥1,500,000 (Direct Cost: ¥1,500,000) Fiscal Year 1985: ¥2,700,000 (Direct Cost: ¥2,700,000)
Keywords	drift chamber / xenon gas / <Lorent_3> angle / flash ADC / synchrotron radiation / エックス線
Research Abstract	For a method to identify electrons by detecting synchrotron X rays, it is important to understand properties of xenon gas, which has high absorption efficiency for X rays, as a drift chamber gas. We feel that we accomplished this purpose in our research project. We measured drift velocity, gas gain, and <Lorent_3> angle which is the angle between the direction of drifting electrons and electric field due to magnetic field. Our data on drift velocities and gas gain agreed well with the previously published data by other groups. On the other hand, our measurements of <Lorent_3> angle for xenon gas is the first measurement. Our data indicates that the <Lorent_3> angle is much larger than we expect based on a simple model of the kinetic theory of gas. We could reduce the angle somewhat by changing the quench gas mixing fraction, but still much larger than our expectation. We studied the signal readout scheme of using the flash ADC which records the entire waveform by 100MHz sampling speed. Analysis of charged particle tracks by this method gave the same result as can be obtained by the ordinary method. Identifying energy clusters caused by X rays by this method must be further investigated.