  We calculate the shape of the photon spectrum for $B\rightarrow X_{s}+\gamma$
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.
