Design & development of Hard X-ray imaging detector using Scintillator and Si Photomultiplier

There are various astrophysical phenomena which are of great importance and interest such as stellar explosions, Gamma ray bursts etc. There is also a growing interest in exploring the celestial sources in hard X-rays. High sensitive instruments are essential to perform the detailed studies of these cosmic accelerators and explosions. Hard X-ray imaging detectors having high absorption efficiency and mm spatial resolution are the key requirements to locate the generation of these astrophysical phenomenon. We hereby present a detector module which consists of a single CsI scintillation detector of size 15 x 15 x 3 mm(3). The photon readout is done using an array of Silicon Photomultipliers (SiPMs). SiPM is a new development in the field of photon detection and can be described as 2D array of small (hundreds of mu m(2)) avalanche photodiodes. We have achieved a spatial resolution of 0.5 mm with our initial setup. By using the array of these detector modules, we can build the detector with a large sensitive area with a very high spatial resolution. This paper presents the experimental details for single detector module using CsI (Tl) scintillator and SiPM and also presents the preliminary results of energy and position measurement. The GEANT4 simulation has also been carried out for the same geometry.