Detecting Nutau Oscillations as PeV Energies

It is suggested that a large deep underocean neutrino detector, given the presence of significant numbers of neutrinos in the PeV range as predicted by various models of Active Galactic Nuclei, can make unique measurements of the properties of neutrinos. It will be possible to observe the existence of the nu_tau, measure its mixing with other flavors, in fact test the mixing pattern for all three flavors based upon the mixing parameters suggested by the atmospheric and solar neutrino data, and measure the nu_tau cross section. The key signature is the charged current nu_tau interaction, which produces a double cascade, one at either end of a minimum ionizing track. At a few PeV these cascades would be separated by roughly 100 m, and thus be easily resolvable in DUMAND and similar detectors. Future applications are precise neutrino astronomy and earth tomography.Comment: 10 Pages, 2 figs included, 15 May 1994, Preprint DUMAND-3-9

Up-Down Asymmetry of Neutral Current Events as a Diagnostic for Nu_mu - Nu-st Versus Nu_mu- Nu_tau Oscillations

We show that the asymmetry in the neutral current events (e.g. Nu N -> Nu N pi^0) can be used to discriminate between Nu_mu - Nu_tau and Nu_mu - Nu_st mixing as being responsible for the atmospheric neutrino anomaly. Specifically, A_N vanishes for Nu_mu - Nu_tau mixing and is about 2/3 A_mu for Nu_mu - Nu_st mixing.Comment: 3pages, 1 figur

Dark Matter Detection With Electron Neutrinos in Liquid Scintillation Detectors

We consider the prospects for liquid scintillation experiments (with a focus on KamLAND) to detect the flux of electron neutrinos arising from dark matter annihilation in the core of the sun. We show that, with data already taken, KamLAND can provide the greatest sensitivity to the dark matter-proton spin-dependent scattering cross-section for dark matter lighter than 20 GeV. It is also possible to probe the dark matter-nucleon spin-independent scattering cross-section for isospin-violating dark matter lighter than 10 GeV. KamLAND can thus potentially confirm the dark matter interpretation of the DAMA and CoGeNT signals, utilizing data already taken.Comment: 5 pages, 4 figures, PDFLaTeX; v2: references added, figures updated, more detailed comparison of liquid scintillation and water Cerenkov detectors (journal version