Reevaluating uncertainties in B ¯ $$ \overline{B} $$ → X s γ decay

Abstract

Abstract The rare decay B ¯ $$ \overline{B} $$ → X s γ is an important probe of physics beyond the standard model. The largest uncertainty on the total rate and the CP asymmetry arises from resolved photon contributions. These appear first at order 1/m b and are related to operators other than Q 7γ in the effective weak Hamiltonian. One of the three leading contributions, Q 1 q − Q 7 γ $$ {Q}_1^q-{Q}_{7\gamma } $$ , is described by a non-local function whose moments are related to HQET parameters. We use recent progress in our knowledge of these parameters to reevaluate the resolved photon contribution to B ¯ $$ \overline{B} $$ → X s γ total rate and CP asymmetry.

Keywords

• CP violation
• Heavy Quark Physics
• Nonperturbative Effects