An X-ray Polarimeter for HXMT Mission

TL;DR

This paper proposes a novel X-ray polarimeter for the HXMT mission, utilizing micropixel gas detectors to enable polarization measurements of celestial X-ray sources, potentially advancing X-ray polarimetry with minimal additional resources.

Contribution

It introduces a new design for X-ray telescopes with polarimeters for the HXMT mission, demonstrating potential for significant advancements in X-ray polarization measurements.

Findings

Design of X-ray telescopes with polarimeters for HXMT

Performance analysis showing capability to detect polarization

Potential for breakthrough in X-ray polarimetry

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 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.