Search for a new bottomonium state decaying to ϒ ( 1 S ) π + π − in pp collisions at √ s = 8 TeV

Abstract

The results of a search for the bottomonium counterpart, denoted as X b , of the exotic charmonium state X(3872) is presented. The analysis is based on a sample of pp collisions at s=8 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 20.7 fb -1 . The search looks for the exclusive decay channel X b →Υ{hooked}(1S)π + π - followed by Υ{hooked}(1S)→μ + μ - . No evidence for an X b signal is observed. Upper limits are set at the 95% confidence level on the ratio of the inclusive production cross sections times the branching fractions to Υ{hooked}(1S)π + π - of the X b and the Υ{hooked}(2S). The upper limits on the ratio are in the range 0.9-5.4% for X b masses between 10 and 11 GeV. These are the first upper limits on the production of a possible X b at a hadron collider.