Title: A Cross-correlation Study between IceCube Neutrino Events and the FERMI Unresolved Gamma-Ray Sky

Abstract

Abstract With the coincident detections of electromagnetic radiation together with gravitational waves (GW170817) or neutrinos (TXS 0506+056), the new era of multimessenger astrophysics has begun. Of particular interest are the searches for correlation between the high-energy astrophysical neutrinos detected by the IceCube Observatory and gamma-ray photons detected by the Fermi Large Area Telescope (LAT). So far, only sources detected by the LAT have been considered in correlation with IceCube neutrinos, neglecting any emission from sources too faint to be resolved individually. Here we present the first cross-correlation analysis considering the unresolved gamma-ray background (UGRB) and IceCube events. We perform a thorough sensitivity study, and, given the lack of identified correlation, we place upper limits on the fraction of the observed neutrinos that would be produced in proton–proton or proton–γ interactions from the population of sources contributing to the UGRB emission and dominating its spatial anisotropy (aka blazars). Our analysis suggests that, under the assumption that there is no intrinsic cutoff and/or hardening of the spectrum above Fermi-LAT energies, and that all gamma rays from the unresolved blazars dominating the UGRB fluctuation field are produced by neutral pions from p–p (p–γ) interactions, up to 60% (30%) of such a population maymore » contribute to the total neutrino events observed by IceCube. This translates into an O (1%) maximum contribution to the astrophysical high-energy neutrino flux observed by IceCube at 100 TeV.« less

Authors:

Negro, Michela  ^[1];

• Search DOE PAGES for author "Negro, Michela"
• Search DOE PAGES for ORCID "0000-0002-6548-5622"

Crnogorčević, Milena  ^[2];

• Search DOE PAGES for author "Crnogorčević, Milena"
• Search DOE PAGES for ORCID "0000-0002-7604-1779"

Burns, Eric  ^[3];

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• Search DOE PAGES for ORCID "0000-0002-2942-3379"

Charles, Eric  ^[4];

• Search DOE PAGES for author "Charles, Eric"
• Search DOE PAGES for ORCID "0000-0002-3925-7802"

Marcotulli, Lea  ^[5];

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• Search DOE PAGES for ORCID "0000-0002-8472-3649"

Caputo, Regina  ^[6]

• Search DOE PAGES for author "Caputo, Regina"
• Search DOE PAGES for ORCID "0000-0002-9280-836X"

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+ Show Author Affiliations

1. University of Maryland, Baltimore, MD (United States); NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
2. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); University of Maryland, College Park, MD (United States)
3. Louisiana State University, Baton Rouge, LA (United States)
4. Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford University, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
5. Yale University, New Haven, CT (United States)
6. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)

Publication Date:

Tue Jul 04 00:00:00 EDT 2023

Research Org.:

SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

Sponsoring Org.:

National Aeronautics and Space Administration (NASA); USDOE Office of Science (SC)

OSTI Identifier:

1995998

Alternate Identifier(s):

OSTI ID: 1996626

Grant/Contract Number:  

AC02-76SF00515; 80GSFC21M0002; NAS5-26555; HST-HF2-51486.001-A

Resource Type:

Accepted Manuscript

Journal Name:

The Astrophysical Journal

Additional Journal Information:

Journal Volume: 951; Journal Issue: 1; Journal ID: ISSN 0004-637X

Publisher:

IOP Publishing

Country of Publication:

United States

Language:

English

Subject:

79 ASTRONOMY AND ASTROPHYSICS; Gamma-rays; Blazars; Neutrino astronomy