Production of ω mesons in pp collisions at √s = 7 TeV

Abstract

The invariant differential cross section of inclusive ω(782) meson production at midrapidity (|y| < 0.5) in pp collisions at √s = 7 TeV was measured with the ALICE detector at the LHC over a transverse momentum range of 2 < pT < 17 GeV/c. The ω meson was reconstructed via its ω → π+π−π0 decay channel. The measured ω production cross section is compared to various calculations: PYTHIA 8.2 Monash 2013 describes the data, while PYTHIA 8.2 Tune 4C overestimates the data by about 50%. A recent NLO calculation, which includes a model describing the fragmentation of the whole vector-meson nonet, describes the data within uncertainties below 6 GeV/c, while it overestimates the data by up to 50% for higher pT. The ω/π0 ratio is in agreement with previous measurements at lower collision energies and the PYTHIA calculations. In addition, the measurement is compatible with transverse mass scaling within the measured pT range and the ratio is constant withCω/π0 = 0.67±0.03 (stat) ±0.04 (sys) above a transverse momentum of 2.5 GeV/c.