Lepton flavor violation in exclusive $$b\rightarrow s$$ b → s decays

Abstract

Starting from the general effective hamiltonian relevant to the b → s transitions, we derive the expressions for the full angular distributions of the B → K ( * ) 1 2 decay modes, as well as for B(B s → 1 2 ) ( 1 = 2 ). We point out the differences in the treatment of the lepton flavor violating modes with respect to the lepton flavor conserving ones. The relevant Wilson coefficients we evaluate in two different scenarios: (i) The (pseudo-)scalar coefficients are obtained using the (pseudo-)scalar coupling extracted from the experimental non-zero value of B(h → μτ ), (ii) we revisit a Z model in which the flavor changing neutral couplings are allowed. We provide the numerical estimates of the branching fractions of the above-mentioned modes in both scenarios.

A leptoquark model to accommodate R K exp < R K SM and R K ∗ exp < R K ∗

“…3 Again, after inserting the values (intervals) of the couplings g qµ L and g qτ L into eq. (2.5), we obtain 4) whereas the branching fractions for similar decay modes can be obtained from the ratios which are independent on the Wilson coefficients [33]:…”

“…, and other similar decay modes [33,34]. As we mentioned in introduction, to obtain both R K < R SM K and R K * < R SM K * we need a NP contribution to the vector and axial Wilson coefficients, and in particular those coupling to the left-handed quark effective current, i.e.…”

“…[30,33], and for three separate intervals in q 2 . To make the comparison with experiment easier we consider three intervals:…”

On the importance of electroweak corrections for B anomalies

“…(2.19) with where 25) and 26) where I i (i = 1, 2, 3) are finite and renormalization scale independent quantities defined as…”

“…[16][17][18][19][20][21][22]. In the recent literature, many studies focused on the experimental signatures implied by the solution of these anomalies in specific scenarios, including kaon observables [23,24], kinematic distributions in B decays [25][26][27][28][29][30][31][32][33][34][35], the lifetime of the B − c meson [36], Υ and ψ leptonic decays [37], tau lepton searches [38,39] and dark matter [40,41].…”