Inclusive J/ψ production in pp collisions at √s=2.76TeV

Abstract

The ALICE Collaboration has measured inclusive J/ψ production in pp collisions at a center-of-mass energy √s = 2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y| < 0.9 and 2.5 < y < 4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L_int^e = 1.1 nb^−1 and L_int^μ = 19.9 nb^−1, and the corresponding signal statistics are N_J/ψ^e+e− = 59 ± 14 and N_J/ψ^μ+μ− = 1364 ± 53. We present dσ_J/ψ/dy for the two rapidity regions under study and, for the forward-y range, d^2σ_J/ψ/dy dp_t in the transverse momentum domain 0 < p_t < 8 GeV/c. The results are compared with previously published results at √s = 7 TeV and with theoretical calculations.