Instrument response generation using high-resolution 3D voxelization of GRBAlpha and VZLUSAT-2 satellites with MEGAlib

Jean-Paul Breuer; Masato Yokota; Yasushi Fukazawa; Hiromitsu Takahashi; Norbert Werner; Jakub Ripa; Marianna Dafcikova; Filip Munz; Masanori Ohno; Balazs Csak; Laszlo Meszaros; Andras Pal; Marcel Frajt; Jan Hudec; Jakub Kapus; Maksim Rezenov; Vladimir Daniel; Juraj Dudas; Petr Svoboda; Hsiang-Kuang Chang; Hao-Min Chang; Chin-Ping Hu; Chih-Hsun Lin; Tsung-Che Liu; Kaustubha Sen; Che-Chih Tsao; Chih-En Wu

arXiv · 2607.06311

Instrument response generation using high-resolution 3D voxelization of GRBAlpha and VZLUSAT-2 satellites with MEGAlib

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Abstract

Pathfinder gamma-ray burst (GRB) detecting CubeSat missions such as GRBAlpha and VZLUSAT-2 have demonstrated the successful application of scintillator detectors with silicon photomultipliers in low Earth orbit (LEO). To produce more comprehensive scientific analysis of the data, the effective area of the detector needs to be characterised at different energies. A large part of this process requires a thorough understanding of the detectors response matrices based on the satellite mass model typically performed through Geant4 and MEGAlib simulations. We use a novel voxelization and binning methodology to turn complex 3D geometries into MEGAlib-compatible versions, and we validate these experiments by showing that the simulation results with Geant4 agree within an order of 10%. We use MEGAlib simulations from various angles around the spacecraft to generate instrumental response matrices for both simple and complex geometries, in the case of GRBAlpha and VZLUSAT-2, respectively.

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Jean-Paul Breuer, Masato Yokota, Yasushi Fukazawa, Hiromitsu Takahashi, Norbert Werner, Jakub Ripa, Marianna Dafcikova, Filip Munz, Masanori Ohno, Balazs Csak, Laszlo Meszaros, Andras Pal, Marcel Frajt, Jan Hudec, Jakub Kapus, Maksim Rezenov, Vladimir Daniel, Juraj Dudas, Petr Svoboda, Hsiang-Kuang Chang, Hao-Min Chang, Chin-Ping Hu, Chih-Hsun Lin, Tsung-Che Liu, Kaustubha Sen, Che-Chih Tsao, Chih-En Wu. 2026-07-07. Instrument response generation using high-resolution 3D voxelization of GRBAlpha and VZLUSAT-2 satellites with MEGAlib. https://arxiv.org/abs/2607.06311

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