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arXiv · 0810.2708

X-ray polarimetry on-board HXMT

Paolo Soffitta·Ronaldo Bellazzini·Gianpiero Tagliaferri·Enrico Costa·Giovanni Pareschi·Stefano Basso·Vincenzo Cotroneo·Massimo Frutti·Francesco Lazzarotto·Fabio Muleri·Alda Rubini·Gloria Spandre·Alessandro Brez·Luca Baldini·Jean Bregeon·Massimo Minuti·Giorgio Matt·Filippo Frontera
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Abstract

The development of micropixel gas detectors, capable to image tracks produced in a gas by photoelectrons, makes possible to perform polarimetry of X-ray celestial sources in the focus of grazing incidence X-ray telescopes. HXMT is a mission by the Chinese Space Agency aimed to survey the Hard X-ray Sky with Phoswich detectors, by exploitation of the direct demodulation technique. Since a fraction of the HXMT time will be spent on dedicated pointing of particular sources, it could host, with moderate additional resources a pair of X-ray telescopes, each with a photoelectric X-ray polarimeter (EXP2, Efficient X-ray Photoelectric Polarimeter) in the focal plane. We present the design of the telescopes and the focal plane instrumentation and discuss the performance of this instrument to detect the degree and angle of linear polarization of some representative sources. Notwithstanding the limited resources, the proposed instrument can represent a breakthrough in X-ray Polarimetry.

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Paolo Soffitta, Ronaldo Bellazzini, Gianpiero Tagliaferri, Enrico Costa, Giovanni Pareschi, Stefano Basso, Vincenzo Cotroneo, Massimo Frutti, Francesco Lazzarotto, Fabio Muleri, Alda Rubini, Gloria Spandre, Alessandro Brez, Luca Baldini, Jean Bregeon, Massimo Minuti, Giorgio Matt, Filippo Frontera. 2008-10-15. X-ray polarimetry on-board HXMT. https://doi.org/10.1117/12.789363

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