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arXiv · 1509.04389

A Transmissive X-ray Polarimeter Design For Hard X-ray Focusing Telescopes

Hong Li·Hua Feng·Jianfeng Ji·Zhi Deng·Li He·Ming Zeng·Tenglin Li·Yinong Liu·Peiyin Heng·Qiong Wu·Dong Han·Yongwei Dong·Fangjun Lu·Shuangnan Zhang
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Abstract

The X-ray Timing and Polarization (XTP) is a mission concept for a future space borne X-ray observatory and is currently selected for early phase study. We present a new design of X-ray polarimeter based on the time projection gas chamber. The polarimeter, placed above the focal plane, has an additional rear window that allows hard X-rays to penetrate (a transmission of nearly 80% at 6 keV) through it and reach the detector on the focal plane. Such a design is to compensate the low detection efficiency of gas detectors, at a low cost of sensitivity, and can maximize the science return of multilayer hard X-ray telescopes without the risk of moving focal plane instruments. The sensitivity in terms of minimum detectable polarization, based on current instrument configuration, is expected to be 3% for a 1mCrab source given an observing time of 10^5 s. We present preliminary test results, including photoelectron tracks and modulation curves, using a test chamber and polarized X-ray sources in the lab.

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Hong Li, Hua Feng, Jianfeng Ji, Zhi Deng, Li He, Ming Zeng, Tenglin Li, Yinong Liu, Peiyin Heng, Qiong Wu, Dong Han, Yongwei Dong, Fangjun Lu, Shuangnan Zhang. 2015-09-15. A Transmissive X-ray Polarimeter Design For Hard X-ray Focusing Telescopes. https://doi.org/10.1117/12.2185435

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