Testing a spin-2 mediator by angular observables in b→sμ+μ−

Abstract

We consider the effects of the spin-2 particle in the b → sμ þ μ − transition assuming that the spin-2 particle couples in a flavor-nonuniversal way to b and s quarks and in the leptonic sector couples only to the muons, thereby only contributing to the process b → sμ þ μ − . The B s −B s transition gives the strong constraint on the coupling of the spin-2 mediator and b and s quarks, while the observed discrepancy from the standard model prediction for the muon anomalous magnetic moment ðg − 2Þ μ serves to constrain the μ coupling to a spin-2 particle. We find that the spin-2 particle can modify the angular observables in the B → Kμ þ μ − and B → K Ã μ þ μ − decays and produce effects that do not exist in the standard model. The generated forward-backward asymmetries in these processes can reach 15%, while other observables for these decays receive tiny effects.

On the Universal Texture in the PA-2HDM for the V-SPIN case

“…s → µ + µ − channel This channel is a rare decay because in the SM it is helicity suppressed and it contains FCNC. 17,28 Since the observation of this decay 29,30 and its compatibility with the SM prediction, 31 it has been used to test several models, 32,33 from the 2HDM 34 to Supersymmetry (See [35] and references therein) and also models with Spin 2 mediators 36 and leptoquarks 37 to mention some examples. A recent experimental study for this decay can be seen in reference [38].…”