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arXiv · 2001.01804

Boresight Alignment of DArk Matter Particle Explorer

Wei Jiang·Xiang Li·Kai-Kai Duan·Zhao-Qiang Shen·Zun-Lei Xu·Jing-Jing Zang·Shi-Jun Lei·Qiang Yuan
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Abstract

The DArk Matter Particle Explorer (DAMPE) can measure $\gamma$-rays in the energy range from a few GeV to about 10 TeV. The direction of each $\gamma$-ray is reconstructed with respect to the reference system of the DAMPE payload. In this paper, we adopt a maximum likelihood method and use the $\gamma$-ray data centered around several bright point-like sources to measure and correct the angular deviation from the real celestial coordinate system, the so called ``boresight alignment'' of the DAMPE payload. As a check, we also estimate the boresight alignment for some sets of simulation data with artificial orientation and obtain consistent results. The time-dependent boresight alignment analysis does not show evidence for significant variation of the parameters.

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Wei Jiang, Xiang Li, Kai-Kai Duan, Zhao-Qiang Shen, Zun-Lei Xu, Jing-Jing Zang, Shi-Jun Lei, Qiang Yuan. 2020-01-06. Boresight Alignment of DArk Matter Particle Explorer. https://doi.org/10.1088/1674-4527/20/6/92

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