pi0 and eta meson production in proton-proton collisions at √s=8 TeV

Research output: Contribution to journalArticlepeer-review

Authors

  • ALICE Collaboration

Colleges, School and Institutes

Abstract

An invariant differential cross section measurement of inclusive pi0 and eta meson production at mid-rapidity in pp collisions at √s=8 TeV was carried out by the ALICE experiment at the LHC. The spectra of pi0 and eta mesons were measured in transverse momentum ranges of 0.3< pT < 35  GeV/c  and 0.5< pT <35  GeV/c , respectively. Next-to-leading order perturbative QCD calculations using fragmentation functions DSS14 for the pi0 and AESSS for the eta overestimate the cross sections of both neutral mesons, although such calculations agree with the measured eta/pi0 ratio within uncertainties. The results were also compared with PYTHIA 8.2 predictions for which the Monash 2013 tune yields the best agreement with the measured neutral meson spectra. The measurements confirm a universal behavior of the eta/pi0 ratio seen for NA27, PHENIX and ALICE data for pp collisions from √s=27.5 GeV to √s=8 TeV within experimental uncertainties. A relation between the pi0 and eta production cross sections for pp collisions at √s=8 TeV is given by pT scaling for pT >3.5  GeV/c . However, a deviation from this empirical scaling rule is observed for transverse momenta below pT <3.5  GeV/c  in the eta/pi0 ratio with a significance of 6.2 sigma.

Details

Original languageEnglish
JournalEuropean Physical Journal C
Volume78
Issue number3
Early online date26 Mar 2018
Publication statusE-pub ahead of print - 26 Mar 2018