Speaker
Description
Polarimetry has become one of the latest potential tools to be used in the study of high energy astrophysical phenomena. Following INTEGRAL polarisation measurements in the gamma ray range and subsequent studies done by AstroSAT and POLAR, polarisation capability has become an important design parameter for future x/gamma ray instruments like Astrogam, Polix, COSI. The scientific communities interest in polarimetry can also be confirmed by the multiple instrument proposals.
Unfortunately, there are currently no confirmed big observatories with polarimetric capabilities in the soft gamma ray range. As a consequence, we are studying the possibility of long-term observation of persistent sources with compact polarimeters flown on nano-satellites. Our proposed mission, ComPol, has been selected by the ORIGINS Excellence Cluster for long-term observation of Cygnus X-1. It should fly by the end of 2025, which opens up the exciting prospect of concurrent observation with NASA's SMEX mission, COSI. ComPol will be capable of detecting a 20% Minimum Detectable Polarisation(MDP) up to 1MeV during its 1 year mission.
An in-orbit verification prototype is currently being prepared to be flown on the ISS in 2023. This prototype will use the same technology as the nano-sat mission albeit in a smaller form-factor. The payload is a Compton Polarimeter consisting of a pixelized SDD scatterer and a CeBr3 calorimeter built by MPP/TUM/Polimi and CEA Saclay respectively; in collaboration with LRSM Munich.
In this talk we will present the calibration campaign of the ISS ComPol polarimeter prototype and its performance.