Rapidity and transverse momentum dependence of inclusive J/$ψ$ production in pp collisions at $\sqrt{s} = 7$ TeV

Paper

Abstract

The ALICE experiment at the LHC has studied inclusive J/

production at central and forward rapidities in pp collisions at

TeV. In this Letter, we report on the first results obtained detecting the J/

through its dilepton decay into

and

pairs in the rapidity range |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero

. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity

= 5.6 nb

and the number of signal events is

(stat.)

28 (syst.); the corresponding figures in the dimuon channel are

= 15.6 nb

and

(stat.)

144(syst.). The measured production cross sections are

(|y|<0.9) = 12.4

1.1 (stat.)

1.8 (syst.) + 1.8 -2.7 (syst.pol.)

b and

(2.5<y<4) = 6.31

0.25 (stat.)

0.76 (syst.) +0.95 -1.96 (syst.pol.)

b. The differential cross sections, in transverse momentum and rapidity, of the J/

were also measured.