2022/02/02 by Alessandro Di Marco, E. Costa, Enrico Costa +44 · 100 citations
Physics and Astronomy · #Artificial intelligence #Astrophysical Phenomena and Observations #Cardinal point #Centroid #Computer science #Detector #Nuclear Physics and Applications #Optics #Particle Detector Development and Performance #Physics #Pixel #Polarimetry #Polarization (electrochemistry) #Scattering #Sensitivity (control systems) #X-ray #astro-ph.IM
paper · pdf · open access · doi:10.3847/1538-3881/ac51c9
published in The Astronomical Journal 163(4), 170 (Institute of Physics) · 16 pages, 2 Tables, 8 Figures Accepted for publication The Astronomical Journal
arxiv created 2022/02/02 · openalex publication_date 2022/03/15 · arxiv updated 2022/03/25 · openalex created_date 2022/04/03 · openalex updated_date 2026/08/06
IXPE is a Small Explorer mission that was launched at the end of 2021 to measure the polarization of X-ray emission from tens of astronomical sources. Its focal plane detectors are based on the Gas Pixel Detector, which measures the polarization by imaging photoelectron tracks in a gas mixture and reconstructing their initial directions. The quality of the single track, and then the capability of correctly determining the original direction of the photoelectron, depends on many factors, e.g., whether the photoelectron is emitted at low or high inclination with respect to the collection plane or the occurrence of a large Coulomb scattering close to the generation point. The reconstruction algorithm used by IXPE to obtain the photoelectron emission direction, also calculates several properties of the shape of the tracks which characterize the process. In this paper we compare several such properties and identify the best one to weight each track on the basis of the reconstruction accuracy. We demonstrate that significant improvement in sensitivity can be achieved with this approach and for this reason it will be the baseline for IXPE data analysis.