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arXiv · 1311.3436

Distinguishing the right-handed up/charm quarks from top quark via discrete symmetries in the standard model extensions

Chao-Shang Huang·Tianjun Li·Xiao-Chuan Wang·Xiao-Hong Wu
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Abstract

We propose a class of the two Higgs doublet Standard models (SMs) with a SM singlet and a class of supersymmetric SMs with two pairs of Higgs doublets, where the right-handed up/charm quarks and the right-handed top quark have different quantum numbers under extra discrete symmetries. Thus, the right-handed up and charm quarks couple to one Higgs doublet field, while the right-handed top quark couples to another Higgs doublet. The quark CKM mixings can be generated from the down-type quark sector. As one of phenomenological consequences in our models, we explore whether one can accommodate the observed direct CP asymmetry difference in singly Cabibbo-suppressed D decays. We show that it is possible to explain the measured values of CP violation under relevant experimental constraints.

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Chao-Shang Huang, Tianjun Li, Xiao-Chuan Wang, Xiao-Hong Wu. 2014-09-09. Distinguishing the right-handed up/charm quarks from top quark via discrete symmetries in the standard model extensions. https://doi.org/10.1103/physrevd.90.055003

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