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X-ray polarimetry with an active-matrix pixel proportional counter

J. K. Black·P. Deines-Jones·S. E. Ready·R. A. Street
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Abstract

We report the first results from an X-ray polarimeter with a micropattern gas proportional counter using an amorphous silicon active matrix readout. With 100% polarized X-rays at 4.5 keV, we obtain a modulation factor of 0.33 +/- 0.03, confirming previous reports of the high polarization sensitivity of a finely segmented pixel proportional counter. The detector described here has a geometry suitable for the focal plane of an astronomical X-ray telescope. Amorphous silicon readout technology will enable additional extensions and improvements.

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J. K. Black, P. Deines-Jones, S. E. Ready, R. A. Street. 2003-03-27. X-ray polarimetry with an active-matrix pixel proportional counter. https://doi.org/10.1016/j.nima.2003.07.015

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