The effect of the sparticle mass spectrum on the conversion of B-L to B

In the context of many leptogenesis and baryogenesis scenarios, B - L (baryon minus the lepton number) is converted into B (baryon number) by non-perturbative B + L violating operators in the SU(2)(L) sector. We correct a common misconversion of B - L to B in the literature in the context of supersymmetry. More specifically, kinematic effects associated with the sparticle masses can be generically important (typically a factor of 2/3 correction in mSUGRA scenarios), and in some cases, it may even flip the sign between B - L and B. We give explicit formulae for converting B - L to B for temperatures approaching the electroweak phase transition temperature from above. Enhancements of B are also possible, leading to a mild relaxation of the reheating temperature bounds coming from gravitino constraints.