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arXiv · 1908.09062

Photon Reconstruction Performance at the CEPC baseline detector

Yuqiao Shen·Hong Xiao·Hengmei Li·Sai Qin·Zheng Wang·Changying Wang·Desheng Zhang·Manqi Ruan
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Abstract

The Circular Electron Positron Collider (CEPC) is a proposed Higgs/Z factory. The photon reconstruction is critical to its physics program. We study the photon reconstruction at the CEPC baseline detector, a Particle Flow oriented detector. We characterized the objective performance at both single-photon and di-photon samples. At the single-photon sample, we quantify the photon conversion rate, the differential reconstruction efficiency and energy resolution, and the identification performance. Using di-photon samples, our analysis shows that the CEPC baseline detector reaches a relative mass resolution of 1.7 - 2.2% of the Higgs boson at the $H\toγγ$ sample, and can reconstruct the $π^0$ with energy as high as 20 - 30 GeV. We also investigate the impact of geometry defects on photon energy resolution and discuss the possible corrections according to the reconstructed photon position.

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Yuqiao Shen, Hong Xiao, Hengmei Li, Sai Qin, Zheng Wang, Changying Wang, Desheng Zhang, Manqi Ruan. 2020-02-21. Photon Reconstruction Performance at the CEPC baseline detector. https://arxiv.org/abs/1908.09062

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