Looking for B → Xsl+l- in a nonminimal universal extra dimensional model

Nonvanishing boundary localized terms significantly modify the mass spectrum and various interactions among the Kaluza-Klein excited states of the five-dimensional universal extra dimensional scenario. In this scenario, we compute the contributions of Kaluza-Klein excitations of gauge bosons and third-generation quarks for the decay process B -> X(s)l(+)l(-), incorporating next-to-leading-order QCD corrections. We estimate the branching ratio as well as the forward-backward asymmetry associated with this decay process. Considering the constraints from some other b -> s observables and electroweak precision data, we show that a significant amount of the parameter space of this scenario has been able to explain the observed experimental data for this decay process. From our analysis, we put a lower limit on the size of the extra dimension by comparing our theoretical prediction for the branching ratio with the corresponding experimental data. Depending on the values of free parameters of the present scenario, the lower limit on the inverse of the radius of compactification (R-1) can be as high as >= 760 GeV. Even this value could be slightly higher if we project the upcoming measurement by the Belle II experiment. Unfortunately, the forward-backward asymmetry of this decay process would not provide any significant limit on R-1 in the present model.