Radiative decay of $b$-quark in a non-Abelian chromomagnetic field

The spectrum and the width of the $b \to s+\gamma $ decay in an external non-Abelian chromomagnetic field simulating the vacuum gluon condensate have been evaluated. The obtained result is consistent with similar nonperturbative corrections calculated earlier by other methods. But the exact functional dependence of the probability of decay on the condensate field intensity disagrees with predictions of other authors who used unfounded approximations. It is shown that the effect of gluon condensate reduces to an increase in the quark mass and to the interaction of the chromatic magnetic moment with the chromomagnetic field.