1. Basic performance of PHENEX: A polarimeter for high ENErgy X rays
- Author
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Kishimoto, Y., Gunji, S., Ishigaki, Y., Kanno, M., Murayama, H., Ito, C., Tokanai, F., Suzuki, K., Sakurai, H., Mihara, T., Kohama, M., Suzuki, M., Hayato, A., Hayashida, K., Anabuki, N., Morimoto, M., Tsunemi, H., Saito, Y., Yamagami, T., and Kishimoto, S.
- Subjects
Crab Nebula -- Research ,Astrophysics -- Research ,Polariscope -- Research ,Business ,Electronics ,Electronics and electrical industries ,Phenex (Optoelectronic device) -- Research - Abstract
We have been developing an instrument named 'PHENEX (Polarimetry for High ENErgy X rays)' to measure polarization in the hard X-ray region. The PHENEX polarimeter consists of detector modules called 'unit counters'. We have investigated the performance of the unit counter, using a highly polarized beam in KEK-PF BL14A. From these measurements, we obtained a detection efficiency of 20% and a modulation factor (analyzing power for polarization) of 53% for 80 keV X rays. Assembling four unit counters, a balloon-flight version was constructed and a preliminary observation of the Crab Nebula was carried out on Jun. 13th, 2006. During this flight, the PHENEX polarimeter observed the Crab for about one hour and detected its hard X rays with a significance of 9[sigma]. From this result, we expect that a PHENEX polarimeter with nine 'unit counters' would achieve a 17% minimum detectable polarization of the Crab Nebula with 3[sigma] significance in a 3-hour observation. Index Terms--Astrophysics, Crab Nebula, hard X ray, PHENEX, polarimeter.
- Published
- 2007