An invariant differential cross section measurement of inclusive pi(0) and eta meson production atmid-rapidity in pp collisions at root s = 8 TeV was carried out by the ALICE experiment at the LHC. The spectra of pi(0) and eta mesons were measured in transverse momentum ranges of 0.3 < p(T) < 35 GeV/c and 0.5 < p(T) < 35 GeV/c, respectively. Next-to-leading order perturbative QCD calculations using fragmentation functions DSS14 for the pi(0) and AESSS for the. overestimate the cross sections of both neutral mesons, although such calculations agree with the measured eta/pi(0) 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/pi(0) ratio seen forNA27, PHENIX and ALICE data for pp collisions from root s = 27.5 GeV to root s = 8 TeV within experimental uncertainties. A relation between the pi(0) and eta production cross sections for pp collisions at root s = 8 TeV is given by m(T) scaling for p(T) > 3.5 GeV/c. However, a deviation from this empirical scaling rule is observed for transverse momenta below p(T) < 3.5 GeV/c in the eta/pi(0) ratio with a significance of 6.2 sigma.

pi(0) and eta meson production in proton-proton collisions at root s=8 TeV

Di Ruzza B;
2018-01-01

Abstract

An invariant differential cross section measurement of inclusive pi(0) and eta meson production atmid-rapidity in pp collisions at root s = 8 TeV was carried out by the ALICE experiment at the LHC. The spectra of pi(0) and eta mesons were measured in transverse momentum ranges of 0.3 < p(T) < 35 GeV/c and 0.5 < p(T) < 35 GeV/c, respectively. Next-to-leading order perturbative QCD calculations using fragmentation functions DSS14 for the pi(0) and AESSS for the. overestimate the cross sections of both neutral mesons, although such calculations agree with the measured eta/pi(0) 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/pi(0) ratio seen forNA27, PHENIX and ALICE data for pp collisions from root s = 27.5 GeV to root s = 8 TeV within experimental uncertainties. A relation between the pi(0) and eta production cross sections for pp collisions at root s = 8 TeV is given by m(T) scaling for p(T) > 3.5 GeV/c. However, a deviation from this empirical scaling rule is observed for transverse momenta below p(T) < 3.5 GeV/c in the eta/pi(0) ratio with a significance of 6.2 sigma.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11369/426721
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