(D* to D + gamma) and (B* to B + gamma) as derived from QCD Sum Rules

Abstract

The method of QCD sum rules in the presence of the external electromagnetic $F_{\mu \nu }$ field is used to analyze radiative decays of charmed or bottomed mesons such as $D^{\ast }\to D\gamma$ and $B^{\ast }\to B\gamma$, with the susceptibilities obtained previously from the study of baryon magnetic moments. Our predictions on $D^{\ast }$ decays agree very well with the experimental data. There are differences among the various theoretical predictions on $B^{\ast }$ decays but the data are not yet available.

Comments: 11 pages, LateX