VERITAS and Multiwavelength Observations of the Blazar B3 2247+381 in Response to an IceCube Neutrino Alert
Abstract While the sources of the diffuse astrophysical neutrino flux detected by the IceCube Neutrino Observatory are still largely unknown, one of the promising methods to improve our understanding of them is investigating the potential temporal and spatial correlations between neutrino alerts and the electromagnetic radiation from blazars. We report on the multiwavelength target-of-opportunity observations of the blazar B3 2247+381, taken in response to an IceCube multiplet alert for a cluster of muon neutrino events compatible with the source location between 2022 May 20 and 2022 November 10. B3 2247+381 was not detected with VERITAS during this time period. The source was found to be in a low-flux state in the optical, ultraviolet, and gamma-ray bands for the time interval corresponding to the neutrino event, but was detected in the hard X-ray band with NuSTAR during this period. We find the multiwavelength spectral energy distribution is described well using a simple one-zone leptonic synchrotron self-Compton radiation model. Moreover, assuming the neutrinos originate from hadronic processes within the jet, the neutrino flux would be accompanied by a photon flux from the cascade emission, and the integrated photon flux required in such a case would significantly exceed the total multiwavelength fluxes and the VERITAS upper limits presented here. The lack of flaring activity observed with VERITAS, combined with the low multiwavelength flux levels, as well as the significance of the neutrino excess being at a 3 σ level (uncorrected for trials), makes B3 2247+381 an unlikely source of the IceCube multiplet. We conclude that the neutrino excess is likely a background fluctuation.
Authors
- A. Falcone (ORCID: https://orcid.org/0000-0002-5068-7344)
- G. Gallagher
- J. V. Mead (ORCID: https://orcid.org/0000-0003-0875-2533)
- A. Acharyya (ORCID: https://orcid.org/0000-0002-2028-9230)
- C. B. Adams (ORCID: https://orcid.org/0000-0002-9021-6192)
- J. H. Buckley (ORCID: https://orcid.org/0000-0001-6391-9661)
- W. Benbow (ORCID: https://orcid.org/0000-0003-2098-170X)
- P. Bangale (ORCID: https://orcid.org/0000-0002-3886-3739)
- J. T. Bartkoske (ORCID: https://orcid.org/0000-0002-9675-7328)
- Q. Feng (ORCID: https://orcid.org/0000-0001-6674-4238)
- Jessie L. Christiansen (ORCID: https://orcid.org/0000-0002-8035-4778)
- M. Errando (ORCID: https://orcid.org/0000-0002-1853-863X)
- M. Ahlers (ORCID: https://orcid.org/0000-0003-0709-5631)
- A. Duerr (ORCID: https://orcid.org/0000-0003-1716-4119)
- M. Escobar Godoy
- A. Søgaard (ORCID: https://orcid.org/0000-0002-0823-056X)
- Dustin J. Foote
Institutions
- Institute of Particle Physics (CA)
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2025-03-20
- DOI
- https://doi.org/10.3847/1538-4357/adb30c
- Citations
- 3
- Primary Topic
- Astrophysics and Cosmic Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 5.61
Funders
- National Science Foundation
- Smithsonian Institution
- U.S. Department of Energy
- National Aeronautics and Space Administration
- University of Wisconsin-Madison
- Nvidia
- Michigan State University
- Villum Fonden
- Polarforskningssekretariatet
- Marquette University
- Western Canada Research Grid
- Barnard College
- Space Telescope Science Institute
- National Energy Research Scientific Computing Center
- European Commission
- Queen's University Belfast
- National Research Foundation
- Deutsche Forschungsgemeinschaft
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Bundesministerium für Bildung und Forschung
- Fonds De La Recherche Scientifique - FNRS
- Belgian Federal Science Policy Office
- Fonds Wetenschappelijk Onderzoek
- Queen's University
- Nuclear Safety and Security Commission
- National Research Foundation of Korea
- Knut och Alice Wallenbergs Stiftelse
- Santen
- Vetenskapsrådet
- RWTH Aachen University
- Chiba University
- Helmholtz Alliance for Astroparticle Physics
- Alliance de recherche numérique du Canada
- Office of Science
- College of Engineering, Michigan State University
- Natural Sciences and Engineering Research Council of Canada
- Science and Technology Facilities Council
- Deutsches Elektronen-Synchrotron
- Japan Society for the Promotion of Science
- Marsden Fund
- Institute for Global Prominent Research, Chiba University
- Office of Polar Programs
- Office of Advanced Cyberinfrastructure
- Office of Experimental Program to Stimulate Competitive Research