Production of radioactive isotopes through cosmic muon spallation in KamLAND


Journal Article

Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in ν detectors, double-β-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of C11. Data from the Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillators, and for checking estimates from current simulations based upon MUSIC, FLUKA, and GEANT4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be Yn=(2.8±0.3)×10-4μ-1g-1cm2. For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment. © 2010 The American Physical Society.

Full Text

Duke Authors

Cited Authors

  • Abe, S; Enomoto, S; Furuno, K; Gando, Y; Ikeda, H; Inoue, K; Kibe, Y; Kishimoto, Y; Koga, M; Minekawa, Y; Mitsui, T; Nakajima, K; Nakamura, K; Nakamura, M; Shimizu, I; Shimizu, Y; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Terashima, A; Watanabe, H; Yonezawa, E; Yoshida, S; Kozlov, A; Murayama, H; Busenitz, J; Classen, T; Grant, C; Keefer, G; Leonard, DS; McKee, D; Piepke, A; Banks, TI; Bloxham, T; Detwiler, JA; Freedman, SJ; Fujikawa, BK; Gray, F; Guardincerri, E; Hsu, L; Ichimura, K; Kadel, R; Lendvai, C; Luk, KB; O'Donnell, T; Steiner, HM; Winslow, LA; Dwyer, DA; Jillings, C; Mauger, C; McKeown, RD; Vogel, P; Zhang, C; Berger, BE; Lane, CE; Maricic, J; Miletic, T; Batygov, M; Learned, JG; Matsuno, S; Pakvasa, S; Foster, J; Horton-Smith, GA; Tang, A; Dazeley, S; Downum, KE; Gratta, G; Tolich, K; Bugg, W; Efremenko, Y; Kamyshkov, Y; Perevozchikov, O; Karwowski, HJ; Markoff, DM; Tornow, W; Heeger, KM; Piquemal, F; Ricol, JS; Decowski, MP

Published Date

  • February 23, 2010

Published In

Volume / Issue

  • 81 / 2

Electronic International Standard Serial Number (EISSN)

  • 1089-490X

International Standard Serial Number (ISSN)

  • 0556-2813

Digital Object Identifier (DOI)

  • 10.1103/PhysRevC.81.025807

Citation Source

  • Scopus