Probing the flavour structure of supersymmetry breaking with rare B-processes — a beyond leading order analysis

In the framework of minimal supersymmetry with general flavour mixing in thesquark sector we consider dominant beyond leading order (BLO) effects in therare processes $\bar{B}\to X_s\gamma$, $\bar{B}_s\mu^+\mu^-$ and$\bar{B}_s-B_s$ mixing. We present analytic expressions for corrected vertices,which are applicable in general, and provide a recipe for the inclusion of thedominant and subdominant BLO effects in existing LO calculations. We alsoderive similar expressions in the mass insertion approximation. We investigatein more detail the focusing effect pointed out in our earlier work, which, atlarge $\tan\beta$ and $\mu>0$, leads to a reduced supersymmetric contributionto the above processes. We also find that, in some cases, flavour dependence,that accidentally cancels at leading order, can reappear at BLO. We furtherinclude electroweak corrections, which, while generally subdominant, in somecases may have a substantial effect. For example, their contribution to thecharged Higgs vertex in $\bar{B}\to X_s\gamma$ can be of the order of 20% atBLO. They can also reduce the contribution of LL insertions to$\bar{B}_s\to\mu^+\mu^-$ and $\bar{B}_s-B_s$ mixing by up to 20%, even at theLO. We also analyse radiative generation of CKM elements and find thepossibility that the CKM matrix elements $K_{ts}$ and $K_{cb}$ can be generatedentirely by LR insertions. This work constitutes the first complete analysis ofdominant BLO effects in the GFM scenario.Comment: 74 page