GRBAlpha: The smallest astrophysical space observatory : I. Detector design, system description, and satellite operations

• Authors: PÁL András; OHNO Masanori; MÉSZÁROS László; WERNER Norbert; ŘÍPA Jakub; CSÁK Balázs; DAFČÍKOVÁ Marianna; FRAJT Marcel; FUKAZAWA Yasushi; HANÁK Peter; HUDEC Ján; HUSÁRIKOVÁ Nikola; KAPUŠ Jakub; KASAL Miroslav; KOLÁŘ Martin; KOLEDA Martin; LASZLO Robert; LIPOVSKÝ Pavol; MIZUNO Tsunefumi; MÜNZ Filip; NAKAZAWA Kazuhiro; REZENOV Maksim; ŠMELKO Miroslav; TAKAHASHI Hiromitsu; TOPINKA Martin; URBANEC Tomáš; RIFFALD SOUZA BREUER Jean-Paul Bernhard; BOZÓKI Tamás; DÁLYA Gergely; ENOTO Teruaki; FREI Zsolt; FRISS Gergely; GALGÓCZI Gábor; HROCH Filip; ICHINOHE Yuto; KAPÁS Kornél; KISS László L.; MATAKE Hiroto; ODAKA Hirokazu; POON Helen; POVALAČ Aleš; TAKÁTSY János; TORIGOE Kento; UCHIDA Nagomi; UCHIDA Yuusuke
• Year of publication: 2023
• Type: Article in Periodical
• Magazine / Source: Astronomy & Astrophysics
• MU Faculty or unit: Faculty of Science

web

• https://arxiv.org/abs/2302.10048
• https://doi.org/10.1051/0004-6361/202346182

• Doi: http://dx.doi.org/10.1051/0004-6361/202346182
• Keywords: instrumentation: detectors; space vehicles: instruments; gamma rays: general
• Description: Aims. Since it launched on 22 March 2021, the 1U-sized CubeSat GRBAlpha operates and collects scientific data on high-energy transients, making it the smallest astrophysical space observatory to date. GRBAlpha is an in-orbit demonstration of a gamma-ray burst (GRB) detector concept suitably small to fit into a standard 1U volume. As was demonstrated in a companion paper, GRBAlpha adds significant value to the scientific community with accurate characterization of bright GRBs, including the recent outstanding event of GRB 221009A. Methods. The GRB detector is a 75 × 75 × 5 mm CsI(Tl) scintillator wrapped in a reflective foil (ESR) read out by an array of SiPM detectors, multi-pixel photon counters by Hamamatsu, driven by two separate redundant units. To further protect the scintillator block from sunlight and protect the SiPM detectors from particle radiation, we applied a multi-layer structure of Tedlar wrapping, anodized aluminium casing, and a lead-alloy shielding on one edge of the assembly. The setup allows observations of gamma radiation within the energy range of 70–890 keV with an energy resolution of ~30%. Results. Here, we summarize the system design of the GRBAlpha mission, including the electronics and software components of the detector, some aspects of the platform, and the current semi-autonomous operations. In addition, details are given about the raw data products and telemetry in order to encourage the community to expand the receiver network for our initiatives with GRBAlpha and related experiments.

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• MUNI Award in Science and Humanities 3
• Integrated Activities for the High Energy Astrophysics Domain