Improved Characterization of the Astrophysical Muon–neutrino Flux with 9.5 Years of IceCube Data
Name
Abbasi_2022_ApJ_928_50.pdf
Description
Published version
Size
1.97 MB
Format
Adobe PDF
Checksum (MD5)
d2083e4e077f8f70e31d6591d9be7723
Author(s)
Conrad, Janet
Date Issued
March 1, 2022
Journal
The Astrophysical Journal
Publisher
American Astronomical Society
Citation
Conrad, Janet. 2022. "Improved Characterization of the Astrophysical Muon–neutrino Flux with 9.5 Years of IceCube Data." The Astrophysical Journal, 928 (1).
Version
Final published version
Abstract
We present a measurement of the high-energy astrophysical muon–neutrino flux with the IceCube Neutrino Observatory. The measurement uses a high-purity selection of 650k neutrino-induced muon tracks from the northern celestial hemisphere, corresponding to 9.5 yr of experimental data. With respect to previous publications, the measurement is improved by the increased size of the event sample and the extended model testing beyond simple power-law hypotheses. An updated treatment of systematic uncertainties and atmospheric background fluxes has been implemented based on recent models. The best-fit single power-law parameterization for the astrophysical energy spectrum results in a normalization of ${\phi }_{@100\mathrm{TeV}}^{{\nu }_{\mu }+{\bar{\nu }}_{\mu }}={1.44}_{-0.26}^{+0.25}\times {10}^{-18}\,{\mathrm{GeV}}^{-1}{\mathrm{cm}}^{-2}{{\rm{s}}}^{-1}{\mathrm{sr}}^{-1}$ and a spectral index ${\gamma }_{\mathrm{SPL}}={2.37}_{-0.09}^{+0.09}$, constrained in the energy range from 15 TeV to 5 PeV. The model tests include a single power law with a spectral cutoff at high energies, a log-parabola model, several source-class-specific flux predictions from the literature, and a model-independent spectral unfolding. The data are consistent with a single power-law hypothesis, however, spectra with softening above one PeV are statistically more favorable at a two-sigma level.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.3847/1538-4357/ac4d29
