Exclusive J/ψ and ψ(2S) vector meson production has been observed in the dimuon channel using the LHCb detector. The cross-section times branching fractions to two muons with pseudorapidities between 2.0 and 4.5 are measured to be σ(pp → J/ψ (→ μ+ μ−))(2.0 < η_μ± < 4.5) = 307 ± 21 ± 36 pb, σ(pp → ψ(2S) (→ μ+ μ−))(2.0 < η_μ± < 4.5) = 7.8 ± 1.3 ± 1.0 pb, where the first uncertainties are statistical and the second are systematic. The measurements are found to be in good agreement with results from previous experiments and theoretical predictions. The J/ψ photoproduction cross-section has been measured as a function of the photon-proton centre-of-mass energy. The results are consistent with measurements obtained at HERA and confirm a similar power law behaviour for the photoproduction cross-section.
Exclusive J/ψ and ψ(2S) Production in pp Collisions at √s = 7 TeV
CARBONE, ANGELO;GALLI, DOMENICO;PATRIGNANI, CLAUDIA;PERAZZINI, STEFANO;VAGNONI, VINCENZO MARIA;ZANGOLI, MARIA;
2013
Abstract
Exclusive J/ψ and ψ(2S) vector meson production has been observed in the dimuon channel using the LHCb detector. The cross-section times branching fractions to two muons with pseudorapidities between 2.0 and 4.5 are measured to be σ(pp → J/ψ (→ μ+ μ−))(2.0 < η_μ± < 4.5) = 307 ± 21 ± 36 pb, σ(pp → ψ(2S) (→ μ+ μ−))(2.0 < η_μ± < 4.5) = 7.8 ± 1.3 ± 1.0 pb, where the first uncertainties are statistical and the second are systematic. The measurements are found to be in good agreement with results from previous experiments and theoretical predictions. The J/ψ photoproduction cross-section has been measured as a function of the photon-proton centre-of-mass energy. The results are consistent with measurements obtained at HERA and confirm a similar power law behaviour for the photoproduction cross-section.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.