2015/11/30 by Xiao-Dong Cheng, Ya-Dong Yang, X. Yuan +1
Mathematics · Physics and Astronomy · #Asymmetry #Black Holes and Theoretical Physics #Combinatorics #Geometry #Higgs boson #Mathematical physics #Mathematics #Observable #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Symmetry (geometry) #Two-Higgs-doublet model #Type (biology) #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-016-3930-2
published as Eur.Phys.J.C 76(2016) 3,151 · 27 pages, 2 tables, 4 figures; v2: a brief introduction to 2HDM added, matches published version
openalex publication_date 2016/03/01 · arxiv created 2016/03/23 · arxiv updated 2016/03/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We revisit the rare leptonic decay Bs → μ + μ - in the two-Higgs doublet models (2HDMs) with a softly broken Z2 symmetry, namely type-I, type-II, type-X and type-Y 2HDMs. We have derived the relevant full one-loop Wilson coefficients of the four 2HDMs from the recent calculation in the aligned 2HDM by Li, Lu and Pich, which could be mapped to all the four 2HDMs for both large and small tan β . It is found that a new term associated with the soft Z2 symmetry breaking parameter M can be enhanced by tan 2β in the type-II 2HDM, which has not been considered in the literature. Imposing both theoretical and experimental constraints, we have renewed the bounds on the parameter spaces of the four 2HDMs. Different from our previous paper, however, we find that all the four 2HDMs give sizable and similar contributions to \mathcal B(Bs → μ + μ -) within the stringently restricted parameter spaces, but very tiny as regards the mass-eigenstate rate asymmetry \mathcal AΔ Γ ; this makes it unfeasible to discriminate the four types of 2HDM with the correlations between the observables in Bs → μ + μ - decay.