Year: 2019
Type: article
Abstract: There is a +2σ deviation in the average Higgs-signal strength for all the 7+8+13 TeV data up to Summer 2018. We find that a slight reduction of the bottom-Yukawa coupling can fit the data better than the standard model. We suggest an extension with a vector-like quark doublet, of which the right-handed component of b′ mixes nonnegligibly with the standard model b quark. We show that the mixing would induce a reduction of the bottom Yukawa coupling. Simultaneously, the coupling of the Z boson to the right-handed b quark increases, which could reduce the forward-backward asymmetry of bottom production at LEP and bring it closer to the experimental value. However, such a mixing is in tension with the ratio Rb of the partial width Z→bb¯ to the total hadronic width, and with the total hadronic width of the Z boson.
Source: Physics Letters B
Institutions: National Central University, Konkuk University, National Tsing Hua University, National Center for Theoretical Sciences, Physics Division, University of Illinois Chicago, Chonnam National University, Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W2908732064