Logo image
Back
Probing the PeV Region in the Astrophysical Neutrino Spectrum using $u_\mu$ from the Southern Sky
Preprint   Open access

Probing the PeV Region in the Astrophysical Neutrino Spectrum using $u_\mu$ from the Southern Sky

R Abbasi, M Ackermann, J Adams, S. K Agarwalla, J. A Aguilar, M Ahlers, J. M Alameddine, N. M Amin, K Andeen, C Argüelles, …
27 Feb 2025
DOI: https://doi.org/10.48550/arxiv.2502.19776
url
https://arxiv.org/abs/2502.19776View
Preprint (Author's original) Open arXiv.org - Non-exclusive license to distribute

Abstract

Physics - High Energy Astrophysical Phenomena
IceCube has observed a diffuse astrophysical neutrino flux over the energy region from a few TeV to a few PeV. At PeV energies, the spectral shape is not yet well measured due to the low statistics of the data. This analysis probes the gap between 1 PeV and 10 PeV by using high-energy downgoing muon neutrinos. To reject the large atmospheric muon background, two complementary techniques are combined. The first technique selects events with high stochasticity to reject atmospheric muon bundles whose stochastic energy losses are smoothed due to high muon multiplicity. The second technique vetoes atmospheric muons with the IceTop surface array. Using 9 years of data, we found two neutrino candidate events in the signal region, consistent with expectation from background, each with relatively high signal probabilities. A joint maximum likelihood estimation is performed using this sample and an independent 9.5-year sample of tracks to measure the neutrino spectrum. A likelihood ratio test is done to compare the single power-law (SPL) vs. SPL+cutoff hypothesis; the SPL+cutoff model is not significantly better than the SPL. High-energy astrophysical objects from four source catalogs are also checked around the direction of the two events. No significant coincidence was found.

Metrics

10 Record Views

Details

Logo image