Search for Astrophysical Neutrinos from 1FLE Blazars with IceCube
Rasha Abbasi, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, Jean-Marco Alameddine, A. A. Alves, N. M. Amin, K. Andeen, T. Anderson, G. Anton, C. Argüelles, Yosuke Ashida, S. Athanasiadou, Spencer Axani, X. Bai, Aswathi Balagopal, M. Baricevic, S. W. Barwick, Vedant Basu, R. Bay, J. J. Beatty, K. Becker, J. Becker Tjus, Jakob Beise, Chiara Bellenghi, S. Benda, S. BenZvi, D. Berley, E. Bernardini, D. Besson, G. Binder, D. Bindig, E. Blaufuss, Summer Blot, Federico Bontempo, Julia Book, Jürgen Borowka, S. Böser, O. Botner, J. Böttcher, Etienne Bourbeau, Federica Bradascio, J. Braun, Bennett Brinson, S. Bron, Jannes Brostean-Kaiser, Ryan T. Burley, Raffaela Busse, Michael Campana, Erin Carnie-Bronca, Kunal Deoskar, Z. Chen, D. Chirkin, K. Choi, Brian Clark, Lew Classen, Alan Coleman, G. H. Collin, A. Connolly, J. M. Conrad, Paul Coppin, Pablo Correa, D. F. Cowen, R. Cross, Christian Dappen, Pranav Dave, C. De Clercq, James DeLaunay, Diyaselis Delgado, H.-P. Dembinski, Kunal Deoskar, Abhishek Desai, P. Desiati, K. D. de Vries, G. de Wasseige, T. DeYoung, A. Diaz, J. C. Díaz–Vélez, Markus Dittmer, Hrvoje Dujmović, M. A. DuVernois, Thomas Ehrhardt, P. Eller, R. Engel, Hannah Erpenbeck, John Evans, P. A. Evenson, Kwok Lung Fan, A. R. Fazely, Anatoli Fedynitch, Nora Feigl, Sebastian Fiedlschuster, Aaron Fienberg, C. Finley, Leander Fischer, D. B. Fox, A. Franckowiak, Edward Friedman
Abstract
Abstract The majority of astrophysical neutrinos have undetermined origins. The IceCube Neutrino Observatory has observed astrophysical neutrinos but has not yet identified their sources. Blazars are promising source candidates, but previous searches for neutrino emission from populations of blazars detected in ≳GeV gamma rays have not observed any significant neutrino excess. Recent findings in multimessenger astronomy indicate that high-energy photons, coproduced with high-energy neutrinos, are likely to be absorbed and reemitted at lower energies. Thus, lower-energy photons may be better indicators of TeV–PeV neutrino production. This paper presents the first time-integrated stacking search for astrophysical neutrino emission from MeV-detected blazars in the first Fermi Large Area Telescope low energy (1FLE) catalog using ten years of IceCube muon–neutrino data. The results of this analysis are found to be consistent with a background-only hypothesis. Assuming an E −2 neutrino spectrum and proportionality between the blazars MeV gamma-ray fluxes and TeV–PeV neutrino flux, the upper limit on the 1FLE blazar energy-scaled neutrino flux is determined to be 1.64 × 10 −12 TeV cm −2 s −1 at 90% confidence level. This upper limit is approximately 1% of IceCube’s diffuse muon–neutrino flux measurement.