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The LHCf experiment

Noda, Koji
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Abstract

The Large Hadron Collider forward (LHCf) experiment has performed measurements of the neutral particles emitted to the very forward region of proton-proton collisions at LHC. This experiment is designed to explore very forward interaction at very high energy, which is relevant to interpretation of the data from cosmic-ray experiments. LHCf detector is well optimized to measure photons in the multi-TeV energy range, and to reconstruct neutral pions with two photons. It can also measure neutrons. The data acquisitions at 0.9 TeV and 7 TeV were completed in 2010. In this paper, single photon energy spectra obtained at 0.9 TeV and transverse energy spectra of neutral pions obtained at 7 TeV will be presented. The results are compared with expectations by hadronic interaction models used for air-shower simulations. We found none of these models agree with the obtained data in the photon energy spectra, while EPOS shows a good agreement in the transverse energy spectra of neural pions. Impacts on cosmic-ray and QCD physics are also discussed.

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSCERN LHCCOMPUTERIZED SIMULATIONCOSMIC RADIATIONDATA ACQUISITIONENERGY SPECTRAINCLUSIVE INTERACTIONSNEUTRAL PARTICLESNEUTRONSPHOTONSPIONS NEUTRALPROTON-PROTON INTERACTIONSQUANTUM CHROMODYNAMICSTEV RANGETRANSVERSE ENERGY

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Noda, Koji. 2012-10-23. The LHCf experiment. https://doi.org/10.1063/1.4763514

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