English

Constraints on the Universal Varying Yukawa Couplings: from SM-like to Fermiophobic

High Energy Physics - Phenomenology 2015-06-04 v3

Abstract

Varying the Standard Model (SM) fermion Yukawa couplings universally by a generic positive scale factor (FYuF_{Yu}), we study the phenomenological fit to the current available experimental results for the Higgs boson search at hadron colliders. We point out that the Higgs production cross section and its decay branching ratio to γγ\gamma\gamma can be varied oppositely by FYuF_{Yu} to make their product almost invariant. Thus, our scenario and the SM Higgs are indistinguishable in the inclusive HγγH\to \gamma\gamma channel. The current measurements on direct Yukawa coupling strength in the Hbbˉ/ττH\to b\bar{b}/\tau\tau channel are not precise enough to fix the scale factor FYuF_{Yu}. The most promising is the vector-boson-fusion channel in which the CMS has already observed possible suppression effect on the Yukawa couplings. Further more, the global χ2\chi^2 fit of the experimental data can get the optimal value by introducing a suppression factor FYu1/2F_{Yu}\sim1/2 on the SM Yukawa couplings.

Keywords

Cite

@article{arxiv.1203.5083,
  title  = {Constraints on the Universal Varying Yukawa Couplings: from SM-like to Fermiophobic},
  author = {Tianjun Li and Xia Wan and You-kai Wang and Shou-hua Zhu},
  journal= {arXiv preprint arXiv:1203.5083},
  year   = {2015}
}

Comments

16 pages, 12 figures, 5 tables, update analysis is supplemented