2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45686We study the effect of the FCNC on rare $B$ decays in the beyond standard model with vector like singlet quarks. It has been shown that $b \rightarrow s γ$ does not receive sizable contribution compared with that of the standard model while $b \rightarrow d γ$, $b \rightarrow s(d) l^+ l^-$, can be changed from the predictions of the standard model.7 pages, Proceeding of 1994 International Workshop on B Physics in Nagoya (World Scientific, 1995) 314, LaTeX, no figuresHigh Energy Physics - Phenomenologytext