Nonminimal universal extra dimensional model confrontsBs→μ+μ−

Abstract

Addition of boundary localised kinetic and Yukawa terms to the action of a 5-dimensional Standard Model would non-trivially modify the Kaluza-Klein spectra and some of the interactions among the Kaluza-Klein excitations compared to the minimal version of this model, in which, these boundary terms are not present. In the minimal version of this framework known as Universal Extra Dimensional model, special assumptions are made about these unknown, beyond the cut-off contributions to restrict the number of unknown parameters of the theory to a minimal. We estimate the contribution of Kaluza-Klein modes to the branching ratios of B s(d) → µ + µ − in the framework of non-minimal Universal Extra Dimensional, at one loop level. The results have been compared to the experimental data to constrain the parameters of this model. From the measured decay branching ratio of B s → µ + µ − (depending on the values of boundary localised parameters) lower limit on R −1 can be as high as 800 GeV. We have briefly reviewed the bounds on nmUED parameter space coming from electroweak precision observables. The present analysis (B s → µ + µ − ) has ruled out new regions of parameter space in comparison to the analysis of electroweak data. We have revisited the bound on R −1 in Universal Extra Dimensional model, which came out to be 454 GeV. This limit on R −1 in Universal Extra Dimensional framework is not as competitive as the limits derived from the consideration of relic density or Standard Model Higgs boson production and decay to W + W − . Unfortunately, B d → µ + µ − decay branching ratio would not set any significant limit on R −1 in a minimal or non-minimal Universal Extra Dimensional model.

Rare top decays in minimal and nonminimal universal extra dimension models

“…These parameters put stringent constraints on many BSM physics scenarios. In nmUED these electroweak precision constraints are discussed in [16,24,28,70]. Clearly in these cases the underlying action and some assumptions are different from our setup.…”

“…16c. Now, in terms of these quantities the electroweak precision observables can be written as [24,28] S nmU ED = 0,…”

“…For completeness first we describe the general set-up of nmUED with BLTs and as we proceed we point out how to revert to mUED. For a more detailed discussion of the model see [16][17][18][19][20][21][22][23][24][25][26][27][28].…”

“…Therefore nmUED has a rich phenomenology compared to the mUED scenario thanks to the presence of the BLT parameters. Some of the recent studies on the phenomenology of the BLTs can be found in [17][18][19][20][21][22][23][24][25][26][27][28]. Now, an important aspect of SM is the absence of flavour changing neutral current (FCNC) interactions at the tree-level.…”

$$B^*_{s,d} \rightarrow \mu ^+ \mu ^-$$ B s , d ∗ → μ + μ - and its impact on $$B_{s,d} \rightarrow \mu ^+ \mu ^-$$ B s , d → μ + μ -

“…Furthermore, the branching fractions of the leptonic decays of scalar meson go through an additional helicity suppression factor by m 2 μ /M 2 S , where a e-mail: nophy0@gmail.com m μ and M S denote the masses of the muon lepton and the scalar meson, respectively. The suppression can be removed in several NP models, such as the two-Higgs-doublet models [3], the minimal supersymmetric standard model [4], the next minimal supersymmetric standard model [5], the dark matter [6], the universal extra dimensional model [7], the lepton universality violation model [8], the fourth generation of fermions [9], and so on [10]. The branching fractions of B s,d → μ + μ − measured by the CMS and LHCb Collaborations [2], and predicted within the SM [1] with NNLO QCD [11] and NLO EW [12] corrections are presented in Table 1.…”