Journal article icon

Journal article

Differential limit on the extremely-high-energy cosmic neutrino flux in the presence of astrophysical background from nine years of IceCube data

Abstract:
We report a quasidifferential upper limit on the extremely-high-energy (EHE) neutrino flux above 5×106  GeV based on an analysis of nine years of IceCube data. The astrophysical neutrino flux measured by IceCube extends to PeV energies, and it is a background flux when searching for an independent signal flux at higher energies, such as the cosmogenic neutrino signal. We have developed a new method to place robust limits on the EHE neutrino flux in the presence of an astrophysical background, whose spectrum has yet to be understood with high precision at PeV energies. A distinct event with a deposited energy above 106  GeV was found in the new two-year sample, in addition to the one event previously found in the seven-year EHE neutrino search. These two events represent a neutrino flux that is incompatible with predictions for a cosmogenic neutrino flux and are considered to be an astrophysical background in the current study. The obtained limit is the most stringent to date in the energy range between 5×106 and 2×1010  GeV. This result constrains neutrino models predicting a three-flavor neutrino flux of E2νϕνe+νμ+ντ≃2×10−8  GeV/cm2 sec sr at 109  GeV. A significant part of the parameter space for EHE neutrino production scenarios assuming a proton-dominated composition of ultra-high-energy cosmic rays is disfavored independently of uncertain models of the extragalactic background light which previous IceCube constraints partially relied on.
Publication status:
Published
Peer review status:
Peer reviewed

Actions

Access Document

Publisher copy:
10.1103/PhysRevD.98.062003

Authors


Publisher:
American Physical Society
Journal:
Physical Review D More from this journal
Volume:
98
Issue:
6
Publication date:
2018-09-12
Acceptance date:
2018-08-26
DOI:
EISSN:
2470-0029
ISSN:
2470-0010


Keywords:
Pubs id:
pubs:885703
UUID:
uuid:cd56379c-6d62-4199-85f2-0c9ec44ed9aa
Local pid:
pubs:885703
Source identifiers:
885703
Deposit date:
2018-09-16
ARK identifier:

Terms of use


Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP