A model for the B → X s + γ decay in the chromomagnetic background
نویسنده
چکیده
We calculate the shape of the photon spectrum for B → Xs + γ decay in the presence of a background chromomagnetic field for the case of SU(2) gauge group. The effect of the external field resembles the Zeeman effect the parton model peak is split into two slightly assymetric peaks, located around the kinematic endpoint. We investigate the analytic properties of the spectrum and calculate the total decay rate. This decay may serve as a model for the investigation of gluon condensate effects and their influence on the shape of the spectrum. Recently, there has been considerable interest in the photon energy spectrum in the decay B → Xs + γ, inspired by the first experimental measurement of this decay by the CLEO collaboration [1]. Considerable theoretical progress has been made by applying Wilson’s operator product expansion
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