Isospin symmetry breaking and direct CP violation in B -> ργwithin and beyond the standard model

Abstract

We discuss the isospin symmetry breaking quantity Δ^{\pm 0} = Γ(B^\pm -> ρ^\pm γ)/[2 Γ(B^0 -> ρ^0 γ)] - 1, and the direct CP violation in B^\pm -> ρ^\pm γwithin and beyond the standard model. After showing that the leading-order calculation would be a good approximation in such models, we argue that measurements of these quantities would be able to disentagle physics beyond the standard model.