A Three-Dimensional Calculation of Atmospheric Neutrino Fluxes

We present a three-dimensional calculation of atmospheric neutrino fluxes using accurate models of the geomagnetic field, hadronic interactions, tracking and decays. Results are presented for the Super-Kamiokande (SK) and Sudbury Neutrino Observatory (SNO) sites using the GEANT-FLUKA hadronic code. We make a comparison with previous one-dimensional calculations and other three-dimensional results. The recently reported geometrical enhancement of low energy, horizontal neutrinos is confirmed. The effect on observed leptons is however, restricted to a small overall increase in flux. We report east-west asymmetries for each of the neutrino species. Revised draft for submission to Astroparticle Physics PACS Numbers: 96.40Tv,98.70.S,96.40Kk,14.60.P 1 The work was supported by the Natural Science and Engineering Research Council of Canada (NSERC). 2 Supported in part by a Faculty of Science scholarship from the University of British Columbia and a summer studentship from the TRIUMF laboratory, Vancouver 3 Corresponding author; email: [email protected] Preprint submitted to Elsevier Preprint 1 February 2008