Measurements of the Upsilon(10860) and Upsilon(11020) resonances via sigma(e(+)e(-) -> Upsilon(nS)pi(+)pi(-))
2016
Abstrakt
We report new measurements of the total cross sections for e(+)e(-) -> Upsilon(nS)pi(+)pi(-) (n = 1, 2, 3) and e(+)e(-) -> b (b) over bar from a high-luminosity fine scan of the region root s = 10.63-11.05 GeV with the Belle detector. We observe that the Upsilon(nS)pi(+)pi(-) spectra have little or no nonresonant component and extract from them the masses and widths of Upsilon(10860) and Upsilon(11020) and their relative phase.
We find M-10860 = (10891.1 +/- 3.2(-1.7)(+0.6)) MeV/c(2) and Gamma(10860) = (53.7(-5.6)(-5.4)(+7.1)(+1.3)) MeV and report first measurements M-11020 = (1098(-2.5)(-2.1)(+6.4)(+9.0)) MeV/c(2), Gamma(11020) = (61(-19)(-20)(+9)(+2)) MeV, and phi(11020) - phi 10860 = (-1.0 +/- 0.4(-0.1)(+1.4)) rad.