Search for exotic hadrons with the CMS experiment

Tetraquarks are exotic hadrons made of four quarks whose existence is predicted by Quantum Chromodynamics. Tetraquarks have been observed by several experiments, like BaBar and LHCb. However, their internal structure is not fully understood, and more experimental observations are needed. This analysis extends, for the first time, the search for tetraquarks made of four bottom quarks in final state 2μ2e (X(bb¯b¯b) → ΥΥ → μ+μ−e+e−), exploiting data collected in 2018 by the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). They correspond to an integrated luminosity of 59.97 fb−1 for proton-proton collisions with a center of mass energy of √s = 13 TeV. The main physical observable is the di-Υ invariant mass spectrum of the 2μ2e system whose signal distribution is expected to peak near the tetraquark mass. Results of this analysis are presented as expected limit on the process cross section as a function of tetraquark mass in the range between 17–30 GeV