Constraints on extended technicolor models from B--> micro+ micro-X.

Abstract

A recent study by Randall and Sundrum shows that models of extended technicolor (ETC) have interesting implications on rare $B$ decays. We extend their study to the decay $B\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}X$. The decay rate is found to be above the standard model prediction roughly by a factor of 4 in the case of "traditional" ETC models, and by a factor of order 30 for ETC models with a GIM mechanism. The current experimental bound is a factor of 5-15 above the standard model prediction, depending on the top-quark mass.