Constraining weak annihilation using semileptonic D decays

Understand

The recently measured semileptonic D_s decay rate can be used to constrain weak annihilation (WA) effects in semileptonic D and B decays.

• We revisit the theoretical predictions for inclusive semileptonic D_{(s)} decays using a variety of quark mass schemes.
• The most reliable results are obtained if the fits to B decay distributions are used to eliminate the charm quark mass dependence, without using any specific charm mass scheme.
• Our fit to the available data shows that WA is smaller than commonly assumed.