  In this paper we consider single leptoquark resonance production associated
with the emission of a hard photon. We have obtained analytical formulae for
differential and total cross sections for the cases of scalar and vector
leptoquarks. We have found that in reactions with scalar leptoquarks there is
no photon radiation in some directions depending on the leptoquark electric
charge (the radiative amplitude zero - the RAZ effect).
  For vector leptoquarks the exact RAZ is present only in the case of
Yang-Mills coupling. We propose to use the RAZ effect to determine the types of
leptoquarks. We conclude also that this effect opens a possibility to measure
the leptoquark anomalous magnetic moment.
