Astrophysical-Neutrino Detection with Angular and Energy Resolution

Abstract

We investigate the improvement in sensitivity to astrophysical point sources of energetic ($\gtrsim 1$ GeV) neutrinos which can be achieved with angular and/or energy resolution of the neutrino-induced muon. As a specific example we consider WIMP annihilation in the Sun and in the Earth as a neutrino source. The sensitivity is improved by using the angular and energy distribution to reduce the atmospheric-neutrino background. Although the specific improvements depend on the backgrounds and assumed sources, the sensitivity to a WIMP signal may be improved, with equal exposure, by up to roughly a factor of two with good angular resolution, and by up to roughly a factor of three with good energy resolution. In case of a positive detection, energy resolution would also improve the measurement of the neutrino energy spectrum and therefore provide information on the WIMP mass and composition.

Comments: 21 pages, 7 eps-figures (included), LaTeX, uses RevTeX and psfig, replaced version with added reference