The measurement of charmonium states produced in proton-neon (pNe) collisions by the LHCb experiment in its fixed-target configuration is presented. The production of J/ψ and ψ(2S) mesons is studied with a beam of 2.5TeV protons colliding on gaseous neon targets at rest, corresponding to a nucleon-nucleon centre-of-mass energy sNN−−−√=68.5GeV. The data sample corresponds to an integrated luminosity of 21.7±1.4 nb−1. The J/ψ and ψ(2S) hadrons are reconstructed in μ+ μ− final states. The J/ψ production cross-section per target nucleon in the centre-of-mass rapidity range y⋆∈[−2.29,0] is found to be 506±8±46 nb/nucleon. The ratio of J/ψ and D0 cross-sections is evaluated to (1.06±0.02±0.09)%. The ψ(2S) to J/ψ relative production rate is found to be (1.67±0.27±0.10)% in good agreement with other measurements involving beam and target nuclei of similar sizes.
Charmonium production in pNe collisions at √ˢNN = 68.5 GeV [Charmonium production in pNe collisions at $$\sqrt{s_{\scriptscriptstyle \text {NN}}} =68.5$$ GeV]
Cardinale, R.;Neri, N.;Petrolini, A.;Sergi, A.;Spadaro Norella, E.;
2023-01-01
Abstract
The measurement of charmonium states produced in proton-neon (pNe) collisions by the LHCb experiment in its fixed-target configuration is presented. The production of J/ψ and ψ(2S) mesons is studied with a beam of 2.5TeV protons colliding on gaseous neon targets at rest, corresponding to a nucleon-nucleon centre-of-mass energy sNN−−−√=68.5GeV. The data sample corresponds to an integrated luminosity of 21.7±1.4 nb−1. The J/ψ and ψ(2S) hadrons are reconstructed in μ+ μ− final states. The J/ψ production cross-section per target nucleon in the centre-of-mass rapidity range y⋆∈[−2.29,0] is found to be 506±8±46 nb/nucleon. The ratio of J/ψ and D0 cross-sections is evaluated to (1.06±0.02±0.09)%. The ψ(2S) to J/ψ relative production rate is found to be (1.67±0.27±0.10)% in good agreement with other measurements involving beam and target nuclei of similar sizes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.