SVOM/VT: Flight Model Verification and Pre-launch Testing

Jian Zhang; Xue-Wu Fan; Gang-Yi Zou; Yu-Lei Qiu; Wei Gao; Wei Wang; Chen-Jie Wang; Ning Qi; Jin-Song Deng; Li-Jun Dan; Yue Pan; Chao Huang; Yun-Fei Du; Guo-Rui Ren; Zhong-Han Sun; Feng-Tao Wang; Wei Li; Bao-Peng Li; Chao Shen; Peng-Fei Chen; Kun Chen; Hui Zhao; Ming Chang; Tao Wang; Li-Pin Xin; Jian-Yan Wei

arXiv · 2604.24268

SVOM/VT: Flight Model Verification and Pre-launch Testing

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Abstract

This paper presents pre-launch testing and calibration results for the SVOM/VT (Space-based Variable Objects Monitor, Visible Telescope) Flight Model (FM), validating its performance under simulated space conditions through thermal vacuum cycling, energy concentration analysis, stray light suppression, and CCD/electronics calibrations (gain, noise, quantum efficiency). The results confirm full compliance with design requirements: stray light suppression achieves point-source transmittance $<10^{-7}$ at $30^\circ$ off-axis, thermal control maintains stable CCD temperatures ($-75^\circ$C for the red channel, $-65^\circ$C for the blue channel), and detection sensitivity meets the limiting magnitude of 22.50 (SNR $>$ 3 with 300 seconds exposure). Early in-orbit tests further validate performance, yielding limiting magnitudes of 22.70 (V-band, red) and 22.78 (blue), consistent with pre-launch specifications.

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Jian Zhang, Xue-Wu Fan, Gang-Yi Zou, Yu-Lei Qiu, Wei Gao, Wei Wang, Chen-Jie Wang, Ning Qi, Jin-Song Deng, Li-Jun Dan, Yue Pan, Chao Huang, Yun-Fei Du, Guo-Rui Ren, Zhong-Han Sun, Feng-Tao Wang, Wei Li, Bao-Peng Li, Chao Shen, Peng-Fei Chen, Kun Chen, Hui Zhao, Ming Chang, Tao Wang, Li-Pin Xin, Jian-Yan Wei. 2026-04-27. SVOM/VT: Flight Model Verification and Pre-launch Testing. https://arxiv.org/abs/2604.24268

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