タムラ タダヒサ   Tamura Tadahisa
  田村 忠久
   所属   神奈川大学  工学部 物理学教室
    神奈川大学大学院  工学研究科 工学専攻(応用物理学領域)
   職種   教授
言語種別 日本語
発行・発表の年月 2011/09
形態種別 学術雑誌
査読 査読あり
標題 Measurement of zero degree single photon energy spectra for √s = 7 TeV proton-proton collisions at LHC
執筆形態 共著
掲載誌名 Physics Letters B
巻・号・頁 703(2),128-134頁
著者・共著者 LHCf Collaboration O. Adriani, L. Bonechi, M. Bongi, G. Castellini, R. D’Alessandro, A. Faus, K. Fukatsu, M. Haguenauer, Y. Itow, K. Kasahara, K. Kawade, D. Macina, T. Mase, K. Masuda, Y. Matsubara, H. Menjo, G. Mitsuka, Y. Muraki, M. Nakai, K. Noda, P. Papini, A.-L. Perrot, S. Ricciarini, T. Sakod, Y. Shimizu, K. Suzuki, T. Suzuki, K. Taki, T. Tamura, S. Torii, A. Tricomi, W.C. Turner, J. Velasco, A. Viciani, K. Yoshida
概要 In early 2010, the Large Hadron Collider forward (LHCf) experiment measured very forward neutral particle spectra in LHC proton-proton collisions. From a limited data set taken under the best beam conditions (low beam-gas background and low occurrence of pile-up events), the single photon spectra at sqrt(s) = 7 TeV and pseudo-rapidity (η) ranges from 8.81 to 8.99 and from 10.94 to infinity were obtained for the first time and are reported in this Letter. The spectra from two independent LHCf detectors are consistent with one another and serve as a cross check of the data. The photon spectra are also compared with the predictions of several hadron interaction models that are used extensively for modeling ultra-high energy cosmic-ray showers. Despite conservative estimates for the systematic errors, none of the models agree perfectly with the measurements. A notable difference is found between the data and the DPMJET 3.04 and PYTHIA 8.145 hadron interaction models above 2 TeV where the models predict higher photon yield than the data. The QGSJET II-03 model predicts overall lower photon yield than the data, especially above 2 TeV in the rapidity range 8.81<η<8.99.