# Probing dark matter particles at CEPC

Liu, Zuowei (0000 0001 2314 964X, grid.41156.37, Department of Physics, Nanjing University, Nanjing, 210093, China) (0000 0001 2256 9319, grid.11135.37, Center for High Energy Physics, Peking University, Beijing, 100871, China) (0000 0004 0632 3097, grid.418741.f, CAS Center for Excellence in Particle Physics, Beijing, 100049, China) ; Xu, Yong-Heng (0000 0001 2314 964X, grid.41156.37, Department of Physics, Nanjing University, Nanjing, 210093, China) ; Zhang, Yu (0000 0001 0085 4987, grid.252245.6, Institute of Physical Science and Information Technology, Anhui University, Hefei, 230026, China) (0000 0004 0632 3097, grid.418741.f, CAS Center for Excellence in Particle Physics, Beijing, 100049, China)

11 June 2019

Abstract: We investigate the capability of the future electron collider CEPC in probing the parameter space of several dark matter models, including millicharged dark matter models, Z ′ portal dark matter models, and effective dark matter operators. In our analysis, the monophoton final state is used as the primary channel to detect dark matter models at CEPC. To maximize the signal to background significance, we study the energy and angular distributions of the monophoton channel arising from dark matter models and from the standard model to design a set of detector cuts. For the Z ′ portal dark matter, we also analyze the Z ′ boson visible decay channel which is found to be complementary to the monophoton channel in certain parameter space. The CEPC reach in the parameter space of dark matter models is also put in comparison with Xenon1T. We find that CEPC has the unprecedented sensitivity to certain parameter space for the dark matter models considered; for example, CEPC can improve the limits on millicharge by one order of magnitude than previous collider experiments for O 1 − 100 $\mathcal{O}(1)-100$ GeV dark matter.

Published in: JHEP 1906 (2019) 009 DOI: 10.1007/JHEP06(2019)009
arXiv: 1903.12114

Fulltext:
XML PDF (PDFA)