Space Observation of Hard X-Rays

Abstract

The energy range of hard X-rays is a key waveband to the study of high energy processes in celestial objects, but still remains poorly explored. The high sensitivity and high resolution imaging is a difficult task in hard X-ray astronomy, which is currently undertaken by complicated and expensive detectors and coded masks. A new inversion technique — the direct demodulation method has been developed in China. The stability, convergency and global optimum property of the method have been proved in the aid of the theory of neural computing. With this technique, wide field and high resolution images can be derived from scanning data of a simple non-position-sensitive detector. The feasibility of this technique has been confirmed by experiment, balloon-borne observation and analysing simulated and real astronomical data. Based on the development of methodology and instrumentation, a Chinese high energy astrophysics mission — Hard X-ray Modulation Telescope (HXMT) has been proposed. In 10–200 keV hard X-ray range, the HXMT mission with its unprecedented sensitivity and imaging ability is expected to play an important role in space astronomy.