Hints of new physics in bottomonium decays and spectroscopy

Abstract

A non-standard light CP-odd Higgs boson could induce a slight (but observable) lepton universality breakdown in Upsilon leptonic decays. Moreover, the mixing between such a pseudoscalar Higgs and ${\eta }_b$ states might shift the mass levels of the latter, thereby changing the values of the $m_{{\rm Y}(nS)}-m_{{\eta }_b(nS)}$ splittings predicted in the standard model. Besides, also the ${\eta }_b$ width could be broader than expected, with potentially negative consequences for its discovery in both $e^{+}{e}^{-}$ and hadron colliders.

Comments: 4 pages, 3 EPS figures, Talk given at BEACH 2004, 27/6/04 - 3/7/04 IIT Chicago