Abstract Details
| Name: Abhay Kumar Affiliation: INAF - Institute of Space Astrophysics and Planetology (IAPS) Conference ID: ASI2025_638 Title : Development of a 1-D position sensitive absorber for a Compton X-ray polarimeter Authors and Co-Authors : Abhay Kumar (1), Santosh Vadawale (2), NPS Mithun (2), and Arpit Patel (2) Abstract Type : Poster Abstract Category : Facilities, Technologies and Data science Abstract : The scientific potential of polarimetry has long been recognized, but due to the challenges in measuring polarization, the field, especially in hard X-rays, still remains largely unexplored. With the recent developments in detector technologies, it is, however, now possible to develop sensitive hard X- ray polarimeters. One such example is the Compton X-ray Polarimeter (CXPOL), a prototype developed at the Physical Research laboratory in India, which consists of a plastic scintillator as an active scatterer surrounded by CsI(Tl) scintillators in a cylindrical array with Si photomultiplier (SiPM) readout from one side. The sensitivity of the instrument can be improved significantly by the use of faster and better light yield scintillators like NaI as absorbers. Further, a position-sensitive scatterer surrounded by position-sensitive absorbers can also provide spectroscopic information by estimating the interaction position along the length and from the known energy depositions in the detectors. The measurement of the polar scattering angle also improves the polarimetric sensitivity of the instrument by reducing the systematic effects introduced by the off-axis events in the azimuthal distribution of photons. The main components of the absorber are 100x20x5 mm3 NaI(Tl) scintillator readout by an array of SiPMs at both ends working in co-incidence. We characterize an absorber and investigate the variation in energy, position resolution, and light yield with the change in the irradiation position along the length of the absorber and the reduction in SiPM noise in co-incidence. In this talk, I will present the first results of the position sensitive absorber design and discuss the experimental results in the context of improvement in the polarimetric sensitivity of the Compton polarimeter. |