Search for a new bottomonium state decaying to Υ(1S)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,root 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 -> Upsilon(1S)pi(+)pi(-) followed by Upsilon(1S) -> mu(+)mu(-). 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 Upsilon(1S)pi(+)pi(-) of the X-b and the Upsilon(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. (C) 2013 CERN. Published by Elsevier B.V. All rights reserved.