Improved measurements of the TeV-PeV extragalactic neutrino spectrum from joint analyses of IceCube tracks and cascades

Abstract

The IceCube South Pole Neutrino Observatory has discovered the presence of a diffuse astrophysical neutrino flux at energies of TeV and beyond using neutrino induced muon tracks and cascade events from neutrino interactions. We present two analyses sensitive to neutrino events in the energy range \SI{1}{TeV} to \SI{10}{PeV}, using more than 10 years of IceCube data. Both analyses consistently reject a neutrino spectrum following a single power-law with significance $>4\sigma$ in favor of a broken power law. We describe the methods implemented in the two analyses, the spectral constraints obtained, and the validation of the robustness of the results. Additionally, we report the detection of a muon neutrino in the MESE sample with an energy of $11.4_{-2.53}^{+2.46}$\,\si{PeV}, the highest energy neutrino observed by IceCube to date. The results presented here show insights into the spectral shape of astrophysical neutrinos, which has important implications for inferring their production processes in a multi-messenger picture.

References in corpus (54)

• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• Asymptotic formulae for likelihood-based tests of new physics
• Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector
• Observation of High-Energy Astrophysical Neutrinos in Three Years of IceCube Data
• The IceCube Neutrino Observatory: Instrumentation and Online Systems
• First observation of PeV-energy neutrinos with IceCube
• IceCube-Gen2: The Window to the Extreme Universe
• Observation and Characterization of a Cosmic Muon Neutrino Flux from the Northern Hemisphere using six years of IceCube data
• Cosmic ray event generator Sibyll 2.1
• Evidence for neutrino emission from the nearby active galaxy NGC 1068
• A combined maximum-likelihood analysis of the high-energy astrophysical neutrino flux measured with IceCube
• The IceCube high-energy starting event sample: Description and flux characterization with 7.5 years of data
• Hidden Cosmic-Ray Accelerators as an Origin of TeV-PeV Cosmic Neutrinos
• Spectrum of cosmic-ray nucleons and the atmospheric muon charge ratio
• Observation of high-energy neutrinos from the Galactic plane
• Atmospheric and Astrophysical Neutrinos above 1 TeV Interacting in IceCube
• Characteristics of the diffuse astrophysical electron and tau neutrino flux with six years of IceCube high energy cascade data
• Energy Reconstruction Methods in the IceCube Neutrino Telescope
• Improved Characterization of the Astrophysical Muon-Neutrino Flux with 9.5 Years of IceCube Data
• The high energy neutrino cross-section in the Standard Model and its uncertainty
• Flavoring Astrophysical Neutrinos: Flavor Ratios Depend on Energy
• Hidden Cores of Active Galactic Nuclei as the Origin of Medium-Energy Neutrinos: Critical Tests with the MeV Gamma-Ray Connection
• Measurement of South Pole ice transparency with the IceCube LED calibration system
• Detection of a particle shower at the Glashow resonance with IceCube
• Uncertainties in Atmospheric Neutrino Fluxes
• Dark Matter Annihilation to Neutrinos
• Ice Cube Observed PeV Neutrinos from AGN Cores
• ANIS: High Energy Neutrino Generator for Neutrino Telescopes
• A simplified view of blazars: the neutrino background
• Vetoing atmospheric neutrinos in a high energy neutrino telescope
• Measurements using the inelasticity distribution of multi-TeV neutrino interactions in IceCube
• Search for neutrinos from decaying dark matter with IceCube
• A generalized self-veto probability for atmospheric neutrinos
• Search for steady point-like sources in the astrophysical muon neutrino flux with 8 years of IceCube data
• Search for Sources of Astrophysical Neutrinos Using Seven Years of IceCube Cascade Events
• Inferring the flavor of high-energy astrophysical neutrinos at their sources
• Characterization of the Astrophysical Diffuse Neutrino Flux using Starting Track Events in IceCube
• Contribution of starburst nuclei to the diffuse gamma-ray and neutrino flux
• New constraints on the origin of medium-energy neutrinos observed by IceCube
• The TeV Diffuse Cosmic Neutrino Spectrum and the Nature of Astrophysical Neutrino Sources
• Diffuse Emission of Galactic High-Energy Neutrinos from a Global Fit of Cosmic Rays
• Neutrino Structure Functions from GeV to EeV Energies
• Efficient propagation of systematic uncertainties from calibration to analysis with the SnowStorm method in IceCube
• A binned likelihood for stochastic models
• Search for Extremely-High-Energy Neutrinos and First Constraints on the Ultrahigh-Energy Cosmic-Ray Proton Fraction with IceCube
• Unified atmospheric neutrino passing fractions for large-scale neutrino telescopes
• In-situ calibration of the single-photoelectron charge response of the IceCube photomultiplier tubes
• A Multi-Component Model for the Observed Astrophysical Neutrinos
• DAEMONFLUX: DAta-drivEn MuOn-calibrated atmospheric Neutrino Flux
• IceCube Neutrinos from Hadronically Powered Gamma-Ray Galaxies
• High-energy neutrino deep inelastic scattering cross sections
• Evidence for a Spectral Break or Curvature in the Spectrum of Astrophysical Neutrinos from 5 TeV--10 PeV
• Improved modeling of in-ice particle showers for IceCube event reconstruction
• Final state radiation from high and ultrahigh energy neutrino interactions

Cited by in corpus (2)

• Evidence for a Spectral Break or Curvature in the Spectrum of Astrophysical Neutrinos from 5 TeV--10 PeV
• Revisiting Disk Winds in Active Galactic Nuclei as an Origin of Cosmic Gamma-ray and Neutrino Backgrounds