Estimate of the Long-Distance Contribution Through b→ sψ to the Bs→γγ Decay Rate

Abstract

The Bs→ϕψ decay is modeled through the inclusive b→ sψ decay. Using the vector meson dominance model, the amplitude for the chain process Bs→ϕ;ψ→ϕγ→γγ is estimated and it is found to be at most 4% of the corresponding amplitude from the O7 type LD contribution. The intermediate amplitude for the process Bs→ϕγ is compared with the corresponding one obtained by a different approach based on the interaction of the virtual charm quark loop with soft gluons.7 Both amplitudes are found to agree within 10%. Further the influence on the branching ratio B (Bs→γγ) SD + LD O7 from inclusive b→ sψ is estimated to be less than 1%.