Production of prompt J/ψ meson pairs in proton-proton collisions at s√ = 7 TeV is measured with the CMS experiment at the LHC in a data sample corresponding to an integrated luminosity of about 4.7 fb−1. The two J/ψ mesons are fully reconstructed via their decays into μ+μ− pairs. This observation provides for the first time access to the high-transverse-momentum region of J/ψ pair production where model predictions are not yet established. The total and differential cross sections are measured in a phase space defined by the individual J/ψ transverse momentum (pTJ/ψ) and rapidity (|yJ/ψ|): |yJ/ψ | < 1.2 for pTJ/ψ > 6.5 GeV/c; 1.2 < |yJ/ψ| < 1.43 for a pT threshold that scales linearly with |yJ/ψ| from 6.5 to 4.5 GeV/c; and 1.43 < |yJ/ψ| < 2.2 for pTJ/ψ > 4.5 GeV/c. The total cross section, assuming unpolarized prompt J/ψ pair production is 1.49 ± 0.07 (stat) ±0.13 (syst) nb. Different assumptions about the J/ψ polarization imply modifications to the cross section ranging from −31% to +27%.
Measurement of prompt J/psi pair production in pp collisions at sqrt(s) = 7 TeV
CANDELISE, VIERI;DELLA RICCA, GIUSEPPE;LA LICATA, CHIARA;MARONE, MATTEO;MONTANINO, DAMIANA;SCHIZZI, ANDREA;UMER, TOMO;
2014-01-01
Abstract
Production of prompt J/ψ meson pairs in proton-proton collisions at s√ = 7 TeV is measured with the CMS experiment at the LHC in a data sample corresponding to an integrated luminosity of about 4.7 fb−1. The two J/ψ mesons are fully reconstructed via their decays into μ+μ− pairs. This observation provides for the first time access to the high-transverse-momentum region of J/ψ pair production where model predictions are not yet established. The total and differential cross sections are measured in a phase space defined by the individual J/ψ transverse momentum (pTJ/ψ) and rapidity (|yJ/ψ|): |yJ/ψ | < 1.2 for pTJ/ψ > 6.5 GeV/c; 1.2 < |yJ/ψ| < 1.43 for a pT threshold that scales linearly with |yJ/ψ| from 6.5 to 4.5 GeV/c; and 1.43 < |yJ/ψ| < 2.2 for pTJ/ψ > 4.5 GeV/c. The total cross section, assuming unpolarized prompt J/ψ pair production is 1.49 ± 0.07 (stat) ±0.13 (syst) nb. Different assumptions about the J/ψ polarization imply modifications to the cross section ranging from −31% to +27%.File | Dimensione | Formato | |
---|---|---|---|
art_10.1007_JHEP09(2014)094.pdf
accesso aperto
Tipologia:
Documento in Versione Editoriale
Licenza:
Creative commons
Dimensione
536.09 kB
Formato
Adobe PDF
|
536.09 kB | Adobe PDF | Visualizza/Apri |
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.