Gamma-ray burst, axion emission and string theory dilaton

The emission of axions from supernovae is an interesting possibility to acc ount for the Gamma-Ray Bursts provided their energy can be effectively conv erted into electromagnetic energy elsewhere. The connection between superno va and gamma-ray bursts has been recently confirmed by the observed correla tion between the burst of April 25, 1998 and the supernova SN1998bw. We arg ue that the axion conversion into photons can be more efficient if one cons iders the coupling between an intermediate scale axion and the string theor y dilaton along with the inclusion of string loops. We also discuss the way dilaton dynamics may allow for a more effective energy exchange with elect romagnetic radiation in the expansion process of fireballs. (C) 1999 Elsevi er Science B.V. All rights reserved.