The inclusive photon energy spectra measured by the Large Hadron Collider forward (LHCf) experiment in the very forward region of LHC proton-proton collisions at root s = 900 GeV are reported. The results from the analysis of 0.30 nb(-1) of data collected in May 2010 in the two pseudorapidity regions of eta > 10.15 and 8.77 < eta <9.46 are compared with the predictions of the hadronic interaction models DPMJET 3.04, EPOS 1.99, PYTHIA 8.145, QGSJET II-03 and SIBYLL 2.1, which are widely used in ultra-high energy cosmic ray experiments. EPOS 1.99 and SIBYLL 2.1 show a reasonable agreement with the spectral shape of the experimental data, whereas they predict lower cross-sections than the data. The other models. DPMJET 3.04, QGSJET II-03 and PYTHIA 8.145, are in good agreement with the data below 300 GeV but predict harder energy spectra than the data above 300 GeV. The results of these comparisons exhibited features similar to those for the previously reported data for root s = 7 TeV collisions. (c) 2012 Elsevier B.V. All rights reserved.
Measurement of zero degree inclusive photon energy spectra for root s=900 GeV proton-proton collisions at LHC
TRICOMI, Alessia Rita;
2012-01-01
Abstract
The inclusive photon energy spectra measured by the Large Hadron Collider forward (LHCf) experiment in the very forward region of LHC proton-proton collisions at root s = 900 GeV are reported. The results from the analysis of 0.30 nb(-1) of data collected in May 2010 in the two pseudorapidity regions of eta > 10.15 and 8.77 < eta <9.46 are compared with the predictions of the hadronic interaction models DPMJET 3.04, EPOS 1.99, PYTHIA 8.145, QGSJET II-03 and SIBYLL 2.1, which are widely used in ultra-high energy cosmic ray experiments. EPOS 1.99 and SIBYLL 2.1 show a reasonable agreement with the spectral shape of the experimental data, whereas they predict lower cross-sections than the data. The other models. DPMJET 3.04, QGSJET II-03 and PYTHIA 8.145, are in good agreement with the data below 300 GeV but predict harder energy spectra than the data above 300 GeV. The results of these comparisons exhibited features similar to those for the previously reported data for root s = 7 TeV collisions. (c) 2012 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
