Evidence for a New Structure in the J /ψp and J /ψ p ¯ Systems in Bs0 →J /ψp p ¯ Decays

Abstract

An amplitude analysis of flavor-untagged Bs0→J/ψpp¯ decays is performed using a sample of 797±31 decays reconstructed with the LHCb detector. The data, collected in proton-proton collisions between 2011 and 2018, correspond to an integrated luminosity of 9 fb-1. Evidence for a new structure in the J/ψp and J/ψp¯ systems with a mass of 4337-4+7 -2+2 MeV and a width of 29-12+26 -14+14 MeV is found, where the first uncertainty is statistical and the second systematic, with a significance in the range of 3.1 to 3.7σ, depending on the assigned JP hypothesis.