2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/148970We compute the rate of the decay $B^- \to μ^- {\bar ν}_μγ$ by a QCD relativistic potential model, with the result: ${\cal B}(B^- \to μ^- {\bar ν}_μγ)=0.9 \cdot 10^{-6}$. We also discuss how this decay mode can be used to access $f_B$.LaTex file, 4 pages, 2 encapsulated PostScript figures. Talk given at the International Conference "Quark Confinement and the Hadron Spectrum II", Como 26-29 June 1996High Energy Physics - Phenomenologytext