A search is reported for near-threshold structures in the J=psi J=psi invariant mass spectrum produced in proton-proton collisions at ffiffi s p 1/4 13 TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135 fb-1. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638 thorn 43 -38 ostat thorn thorn 16 -31 osyst thorn MeV. Another structure with even higher significance is found at a mass of 6847 thorn 44 -28 ostat thorn thorn 48 -20 osyst thorn MeV, which is consistent with the Xo6900 thorn resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134 thorn 48 -25 ostat thorn thorn 41 -15 osyst thorn MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference
New Structures in the J/ψJ/ψ Mass Spectrum in Proton-Proton Collisions at s=13 TeV
Calligaris, L.;Aimè, C.;Asenov, P.;Bianchini, L.;Bossini, E.;Bruschini, D.;Ciocci, M. A.;Cipriani, M.;Donato, S.;Messineo, A.;Musich, M.;Rizzi, A.;Marini, A. C.;
2024-01-01
Abstract
A search is reported for near-threshold structures in the J=psi J=psi invariant mass spectrum produced in proton-proton collisions at ffiffi s p 1/4 13 TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135 fb-1. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638 thorn 43 -38 ostat thorn thorn 16 -31 osyst thorn MeV. Another structure with even higher significance is found at a mass of 6847 thorn 44 -28 ostat thorn thorn 48 -20 osyst thorn MeV, which is consistent with the Xo6900 thorn resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134 thorn 48 -25 ostat thorn thorn 41 -15 osyst thorn MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interferenceI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
