Observation of triple J/ψ meson production in proton-proton collisions
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Tarih
2023
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Nature Portfolio
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Protons consist of three valence quarks, two up-quarks and one down-quark, held together by gluons and a sea of quark-antiquark pairs. Collectively, quarks and gluons are referred to as partons. In a proton-proton collision, typically only one parton of each proton undergoes a hard scattering - referred to as single-parton scattering - leaving the remainder of each proton only slightly disturbed. Here, we report the study of double- and triple-parton scatterings through the simultaneous production of three J/psi mesons, which consist of a charm quark-antiquark pair, in proton-proton collisions recorded with the CMS experiment at the Large Hadron Collider. We observed this process - reconstructed through the decays of J/psi mesons into pairs of oppositely charged muons - with a statistical significance above five standard deviations. We measured the inclusive fiducial cross-section to be 272(-104)(+141) (stat) +/- 17 (syst) fb, and compared it to theoretical expectations for triple-J/psi meson production in single-, double- and triple-parton scattering scenarios. Assuming factorization of multiple hard-scattering probabilities in terms of single-parton scattering cross-sections, double- and triple-parton scattering are the dominant contributions for the measured process.
Açıklama
Anahtar Kelimeler
Double Parton Interactions, P(P)Over-Bar Collisions, Matrix-Element, Jet Events, Helac-Onia, Scatterings, Generator, Pp
Kaynak
Nature Physics
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
