Short distance analysis of B̄→D(∗)0e+e− and B̄→J/ψe+e− Original

Over a large fraction of phase space a combination of an operator product and heavy quark expansions effectively turn the decay B̄→D(∗)0e+e− into a “short distance” process, i.e., one in which the weak and electromagnetic interactions occur through single local operators. These processes have an underlying W-exchange quark diagram topology and are therefore Cabibbo allowed but suppressed by combinatoric factors and short distance QCD corrections. Our technique allows a clearer exploration of these effects. For the decay B̄d,s→J/ψ(ηc)e+e− one must use a non-relativistic (NRQCD) expansion, in addition to an operator product expansion and a heavy quark effective theory expansion. We estimate the decay rates for B̄d,s→J/ψe+e− , B̄d,s→ηce+e− , B̄d,s→D∗0e+e− and B̄d,s→D0e+e− .