TY - JOUR
T1 - Measurement of very forward neutron energy spectra for 7 TeV proton-proton collisions at the Large Hadron Collider
AU - Adriani, O.
AU - Berti, E.
AU - Bonechi, L.
AU - Bongi, M.
AU - Castellini, G.
AU - D'Alessandro, R.
AU - Del Prete, M.
AU - Haguenauer, M.
AU - Itow, Y.
AU - Kasahara, K.
AU - Kawade, K.
AU - Makino, Y.
AU - Masuda, K.
AU - Matsubayashi, E.
AU - Menjo, H.
AU - Mitsuka, G.
AU - Muraki, Y.
AU - Okuno, Y.
AU - Papini, P.
AU - Perrot, A. L.
AU - Ricciarini, S.
AU - Sako, T.
AU - Sakurai, N.
AU - Sugiura, Y.
AU - Suzuki, T.
AU - Tamura, T.
AU - Tiberio, A.
AU - Torii, Shoji
AU - Tricomi, A.
AU - Turner, W. C.
AU - Zhou, Q. D.
PY - 2015/11/12
Y1 - 2015/11/12
N2 - The Large Hadron Collider forward (LHCf) experiment is designed to use the LHC to verify the hadronic-interaction models used in cosmic-ray physics. Forward baryon production is one of the crucial points to understand the development of cosmic-ray showers. We report the neutron-energy spectra for LHC √s=7 TeV proton-proton collisions with the pseudo-rapidity η ranging from 8.81 to 8.99, from 8.99 to 9.22, and from 10.76 to infinity. The measured energy spectra obtained from the two independent calorimeters of Arm1 and Arm2 show the same characteristic feature before unfolding the detector responses. We unfolded the measured spectra by using the multidimensional unfolding method based on Bayesian theory, and the unfolded spectra were compared with current hadronic-interaction models. The QGSJET II-03 model predicts a high neutron production rate at the highest pseudo-rapidity range similar to our results, and the DPMJET 3.04 model describes our results well at the lower pseudo-rapidity ranges. However, no model perfectly explains the experimental results over the entire pseudo-rapidity range. The experimental data indicate a more abundant neutron production rate relative to the photon production than any model predictions studied here.
AB - The Large Hadron Collider forward (LHCf) experiment is designed to use the LHC to verify the hadronic-interaction models used in cosmic-ray physics. Forward baryon production is one of the crucial points to understand the development of cosmic-ray showers. We report the neutron-energy spectra for LHC √s=7 TeV proton-proton collisions with the pseudo-rapidity η ranging from 8.81 to 8.99, from 8.99 to 9.22, and from 10.76 to infinity. The measured energy spectra obtained from the two independent calorimeters of Arm1 and Arm2 show the same characteristic feature before unfolding the detector responses. We unfolded the measured spectra by using the multidimensional unfolding method based on Bayesian theory, and the unfolded spectra were compared with current hadronic-interaction models. The QGSJET II-03 model predicts a high neutron production rate at the highest pseudo-rapidity range similar to our results, and the DPMJET 3.04 model describes our results well at the lower pseudo-rapidity ranges. However, no model perfectly explains the experimental results over the entire pseudo-rapidity range. The experimental data indicate a more abundant neutron production rate relative to the photon production than any model predictions studied here.
KW - Forward neutron production
KW - Hadronic-interaction model
KW - LHC
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U2 - 10.1016/j.physletb.2015.09.041
DO - 10.1016/j.physletb.2015.09.041
M3 - Article
AN - SCOPUS:84942333259
SN - 0370-2693
VL - 750
SP - 360
EP - 366
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
ER -