Method of incident low-energy gamma-ray direction reconstruction in the GAMMA-400 gamma-ray space telescope

International Conference on Particle Physics and Astrophysics

Kheymits, M.D.^1 ; Leonov, A.A.^1 ; Zverev, V.G.^1 ; Galper, A.M.^1,2 ; Arkhangelskaya, I.V.^1 ; Arkhangelskiy, A.I.^1 ; Suchkov, S.I.^2 ; Topchiev, N.P.^2 ; Yurkin, Yu T.^1 ; Bakaldin, A.V.^1 ; Dalkarov, O.D.^2

National Research Nuclear University MEPhI, Kashirskoe Shosse 31, Moscow

115409, Russia^1

P. N. Lebedev Physical Institute, Russian Academy of Sciences, Leninskij Prospekt 53, Moscow

119991, Russia^2

关键词: Angular resolution;    Annihilation process;    Dark matter particles;    Electron-positron pairs;    Gamma-ray bursts (GRBs);    Low energy gamma ray;    Multiple scattering process;    Position-Sensitive Detectors;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/675/3/032012/pdf
DOI  :  10.1088/1742-6596/675/3/032012

来源: IOP

【 摘 要 】

The GAMMA-400 gamma-ray space-based telescope has as its main goals to measure cosmic γ-ray fluxes and the electron-positron cosmic-ray component produced, theoretically, in dark-matter-particles decay or annihilation processes, to search for discrete γ-ray sources and study them in detail, to examine the energy spectra of diffuse γ-rays - both galactic and extragalactic - and to study gamma-ray bursts (GRBs) and γ-rays from the active Sun. Scientific goals of GAMMA-400 telescope require fine angular resolution. The telescope is of a pair-production type. In the converter-tracker, the incident gamma-ray photon converts into electron-positron pair in the tungsten layer and then the tracks are detected by silicon- strip position-sensitive detectors. Multiple scattering processes become a significant obstacle in the incident-gamma direction reconstruction for energies below several gigaelectronvolts. The method of utilising this process to improve the resolution is proposed in the presented work.