Abstract
We calculate the leading-order matrix element for exclusive decays of b→sγ in the quenched approximation of lattice QCD on a ×48 lattice at β=6.2, using an O(a)-improved fermion action. The matrix element is used to extract the on-shell form factor (=0) for B→γ and →φγ, using two different assumptions about the dependence of the form factors for these decays. For B→γ, (=0) is determined to be 0.±0.067 or 0.±0.022 in the two cases. We find the results to be consistent (in the standard model) with the CLEO experimental branching ratio of B(B→γ)=(4.5±1.5±0.9)×.
- Received 19 July 1994
DOI:https://doi.org/10.1103/PhysRevD.51.4955
©1995 American Physical Society