Masses, Widths, and Leptonic Widths of the Higher Upsilon Resonances

Abstract

The masses, total widths, and leptonic widths of three triplet $s$-wave $b\overline{b}$ states $\Upsilon \mathrm{}\left(4S\right)\mathrm{}$, $\Upsilon \mathrm{}\left(5S\right)\mathrm{}$, and $\Upsilon \mathrm{}\left(6S\right)\mathrm{}$ are determined from measurements of the $e^{+}{e}^{-}$ annihilation cross section into hadrons for $10.55<W<\mathrm{}11.25\mathrm{}$ GeV. The resonances are identified from potential model results and their properties are obtained with the help of a simplified coupled-channels calculation. We find $M\left(4S\right)=10.577\mathrm{}$ GeV, $\Gamma \mathrm{}\left(4S\right)=25\mathrm{}$ MeV, ${\Gamma }_{\mathrm{ee}}\mathrm{}\left(4S\right)=0.28\mathrm{}$ keV; $M\left(5S\right)=10.845\mathrm{}$ GeV, $\Gamma \mathrm{}\left(5S\right)=110\mathrm{}$ MeV, ${\Gamma }_{\mathrm{ee}}\mathrm{}\left(5S\right)=0.37\mathrm{}$ keV; $M\left(6S\right)=11.02\mathrm{}$ GeV, $\Gamma \mathrm{}\left(6S\right)=90\mathrm{}$ MeV, ${\Gamma }_{\mathrm{ee}}\mathrm{}\left(6S\right)=0.16\mathrm{}$ keV.