Constraints on the minimal supergravity parameter space from NLO calculation of isospin asymmetry inB→K*γ

The contributions of supersymmetric particles in the isospin symmetry violation in $B\to K^{*}\gamma$ decay mode are investigated. The model parameters are adopted from minimal Supergravity with minimal flavor violation. A complete scan of the mSUGRA parameter space has been performed, using the next to leading supersymmetric contributions to the relevant Wilson coefficients. The results are compared to recent experimental data in order to obtain constraints on the parameter space. We point out that isospin asymmetry can prove to be an interesting observable and imposes severe restrictions on the allowed parameter space, in particular, for large values of $\tan \beta$. The constraints obtained with isospin asymmetry also appear as more restricting than the ones from the branching ratio of $B\to X_s\gamma$.