Some Novel Contributions to Radiative B decay in Supersymmetry without R-parity

By Rishikesh Vaidya, National Central University Taiwan

We present a systematic analysis of all the contributions at the leading log order to thebranching ratio of the inclusive radiative B decay b → s + γ in the framework of supersymmetry without R-parity. The relevant set of four-quark operators involved in QCD running are extended from 6 (within SM and MSSM) to 24, with also many new contributions to the Wilson coefficients of (chromo)magnetic penguins for either chiral structure. We present complete analytical results here without any a priori assumptions on the form of R-parity violation. Mass eigenstate expressions are given, hence the results are free from the commonly adopted mass-insertion approximation. In the numerical analysis, we focus separately on the influence of trilinear lambda-prime couplings and a combination of bilinear and trilinear parameters which have never been investigated before. For the former, we report on the possibility of a few orders of magnitude improvement for the bounds on a few combinations of the lambda-prime couplings. Our study shows that the Wilson coefficients of the current-current operators due to R-parity violation dominate over the direct contributions to the penguins. However, the inter-play of various contributions is complicated due to the QCD corrections which we elaborate here. For the class of bilinear-trilinear combination we obtain very strong bounds for some combinations for which no bounds exist as yet. We also substantiate our numerical results by obtaining analytical expressions for various contributions by perturbative diagonalization of mass matrices with phenomenologially viable assumptions.