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Abstract:

We have repeated a one-dimensional calculation of neutrino fluxes, including the effect of muon polarization on neutrinos from the decay of muons. Fluxes have been calculated as a function of energy and angle with cutoffs appropriate for locations of five deep nucleon-decay experiments. Overall, the e/ ratio increases by 5% (20%) for neutrinos with energies around 200 MeV (2"3 GeV), in agreement with a previous analytic estimate of the effect. © 1989 The American Physical Society.

Abstract:

In this paper we give a complete account of detailed calculations of the flux of neutrinos of atmospheric origin that we have made for detectors at various locations on the globe. The emphasis here is on neutrinos in the energy range around 1 GeV, and we compare the results with recent measurements made with larger underground detectors. A detailed knowledge of the atmospheric cosmic-ray neutrino flux is a prerequisite for evaluating the background for the search for nucleon decay as well as the background for neutrinos of extraterrestrial origin. © 1988 The American Physical Society.

Abstract:

We report a measurement of the flux-integrated $\nu_{\mu}$ charged-current cross sections on water, hydrocarbon, and iron in the T2K on-axis neutrino beam with a mean neutrino energy of 1.5 GeV. The measured cross sections on water, hydrocarbon, and iron are $\sigma^{\rm{H_{2}O}}_{\rm{CC}}$ = (0.840$\pm 0.010$(stat.)$^{+0.10}_{-0.08}$(syst.))$\times$10$^{-38}$cm$^2$/nucleon, $\sigma^{\rm{CH}}_{\rm{CC}}$ = (0.817$\pm 0.007$(stat.)$^{+0.11}_{-0.08}$(syst.))$\times$10$^{-38}$cm$^2$/nucleon, and $\sigma^{\rm{Fe}}_{\rm{CC}}$ = (0.859$\pm 0.003$(stat.) $^{+0.12}_{-0.10}$(syst.))$\times$10$^{-38}$cm$^2$/nucleon respectively, for a restricted phase space of induced muons: $\theta_{\mu}<45^{\circ}$ and $p_{\mu}>$0.4 GeV/$c$ in the laboratory frame. The measured cross section ratios are ${\sigma^{\rm{H_{2}O}}_{\rm{CC}}}/{\sigma^{\rm{CH}}_{\rm{CC}}}$ = 1.028$\pm 0.016$(stat.)$\pm 0.053$(syst.), ${\sigma^{\rm{Fe}}_{\rm{CC}}}/{\sigma^{\rm{H_{2}O}}_{\rm{CC}}}$ = 1.023$\pm 0.012$(stat.)$\pm 0.058$(syst.), and ${\sigma^{\rm{Fe}}_{\rm{CC}}}/{\sigma^{\rm{CH}}_{\rm{CC}}}$ = 1.049$\pm 0.010$(stat.)$\pm 0.043$(syst.). These results, with an unprecedented precision for the measurements of neutrino cross sections on water in the studied energy region, show good agreement with the current neutrino interaction models used in the T2K oscillation analyses.