The Pure Light B Meson Decay

The study of B physics is an important task in particle physics. The rare B meson decays provide a good opportunity for testing the Standard Model(SM), determining the basic parameters and searching for possible new physics beyond the SM. The theorists have done a large number of exploring work and gained great successes, and moreover, in the near future (the next year) CERN Large Hadron Collider beauty experiments (LHC-b), a large number of B mesons can be produced. So the study of B meson rare decays is important in a few years.Pure leptonic decays B_q �' l+l- are difficult to measure in experiments, since helicity suppression gives a very small branching ratio;the B_q�' vv decay is forbidden due to massless of the neutrino. Fortunately, having an extra real photon emitted, the radiative leptonic decays can escape from the helicity suppression, larger branching ratio is expected. Utilizing the B meson wave function which constrained by non-leptonic decays, we give a detailed pheonenological analysis of the decays B_q�'γvv and Bq �'γ l+l- , whose branching ratio orders are around 10^-9. Generally speaking, these channels are sensitive to new physics, and probably they give the evidence and signal of new physics. We hope that these results will be helpful for guiding the future experiments.