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Scalar Dark Matter Effects in Higgs and Top Quark Decays

Xiao-Gang He·Tong Li·Xue-Qian Li·Ho-Chin Tsai
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Abstract

We study possible observational effects of scalar dark matter, the darkon D, in Higgs h and top quark t decay processes, h->DD and t->cDD in the minimal Standard Model (SM) and its two Higgs doublet model (THDM) extension supplemented with a SM singlet darkon scalar field D. We find that the darkon D can have a mass in the range of sub-GeV to several tens of GeV, interesting for LHC and ILC colliders, to produce the required dark matter relic density. In the SM with a darkon, t->cDD only occurs at loop level giving a very small rate, while the rate for Higgs decay h->DD can be large. In THDM III with a darkon, where tree level flavor changing neutral current (FCNC) interaction exists, a sizable rate for t->cDD is also possible.

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Xiao-Gang He, Tong Li, Xue-Qian Li, Ho-Chin Tsai. 2007-01-31. Scalar Dark Matter Effects in Higgs and Top Quark Decays. https://doi.org/10.1142/s0217732307025376

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