Weak radiative decay Λ < inf > b < /inf > → Λ γ and quark-confined effects in the covariant oscillator quark model

Abstract

Motivated by the observation of the decay B → K* γ by the CLEO collaboration, we have systematically analyzed the weak radiative decay Λb → Λ γ, evaluating the confined effects of quarks in the covariant oscillator quark model. This decay process receives both short distance (electromagnetic penguins at the one loop level) and long distance contributions in the quark level. The long distance contributions are analyzed using the vector meson dominance (VMD) method. The estimated branching ratio is found to be 0.23 × 10-5.