Angular power spectrum analysis on current and future high-energy neutrino data

Abstract

Astrophysical neutrino events have been measured in the last couple of years, which show an isotropic distribution, and the current discussion is their astrophysical origin. We use both isotropic and anisotropic components of the diffuse neutrino data to constrain the contribution of a broad number of extra-galactic source populations to the observed neutrino sky. We simulate up-going muon neutrino events by applying statistical distributions for the flux of extragalactic sources, and by Monte Carlo method we exploit the simulation for current and future IceCube, IceCube-Gen2 and KM3NeT exposures. We aim at constraining source populations by studying their angular patterns, for which we assess the angular power spectrum. We leave the characteristic number of sources (N ) as a free parameter, which is roughly the number of neutrino sources over which the measured intensity is divided. With existing two-year IceCube data, we can already constrain very rare, bright sources with N 100. This can be improved to N 10 4 -10 5 with IceCube-Gen2 and KM3NeT with tenyear exposure, constraining the contribution of BL Lacs (N = 6 × 10 2 ). On the other hand, we can constrain weak sources with large number densities, like starburst galaxies (N = 10 7 ), if we measure an anisotropic neutrino sky with future observations.

Loop dominated signals from neutrino portal dark matter

“…Such frameworks are particularly motivated in light of models of neutrino mass generation, which require physics beyond the Standard Model, including new SMsinglet states (sterile neutrinos), which can act as portals to hidden sectors. Neutrino-rich indirect detection signatures in such models have been extensively studied in the literature [12,[15][16][17][18][19][20]. From the point of view of phenomenology, indirect detection of dark matter in neutrinorich final states has recently garnered tremendous interest in the community, driven by sensitive instruments such as IceCube [21], Super-Kamiokande [22], and ANTARES [23], and have also been fueled by anomalous high energy neutrino events at IceCube [24,25], which can be interpreted as hints of decaying dark matter (see, e.g., Refs.…”

“…These require additional considerations, such as inclusion of secondary emission and propagation effects, which are beyond the scope of this paper and have been performed elsewhere (see, e.g., Refs. [12,[15][16][17][18][19][20]).…”