_version_ 1866911824764469248
author van Velzen, Sjoert
Stein, Robert
Gilfanov, Marat
Kowalski, Marek
Hayasaki, Kimitake
Reusch, Simeon
Yao, Yuhan
Garrappa, Simone
Franckowiak, Anna
Gezari, Suvi
Nordin, Jakob
Fremling, Christoffer
Sharma, Yashvi
Yan, Lin
Kool, Erik C.
Stern, Daniel
Veres, Patrik M.
Sollerman, Jesper
Medvedev, Pavel
Sunyaev, Rashid
Bellm, Eric C.
Dekany, Richard G.
Duev, Dimitri A.
Graham, Matthew J.
Kasliwal, Mansi M.
Kulkarni, Shrinivas R.
Laher, Russ R.
Riddle, Reed L.
Rusholme, Ben
author_facet van Velzen, Sjoert
Stein, Robert
Gilfanov, Marat
Kowalski, Marek
Hayasaki, Kimitake
Reusch, Simeon
Yao, Yuhan
Garrappa, Simone
Franckowiak, Anna
Gezari, Suvi
Nordin, Jakob
Fremling, Christoffer
Sharma, Yashvi
Yan, Lin
Kool, Erik C.
Stern, Daniel
Veres, Patrik M.
Sollerman, Jesper
Medvedev, Pavel
Sunyaev, Rashid
Bellm, Eric C.
Dekany, Richard G.
Duev, Dimitri A.
Graham, Matthew J.
Kasliwal, Mansi M.
Kulkarni, Shrinivas R.
Laher, Russ R.
Riddle, Reed L.
Rusholme, Ben
contents The origin of cosmic high-energy neutrinos remains largely unexplained. For high-energy neutrino alerts from IceCube, a coincidence with time-variable emission has been seen for three different types of accreting black holes: (1) a gamma-ray flare from a blazar (TXS 0506+056), (2) an optical transient following a stellar tidal disruption event (TDE; AT2019dsg), and (3) an optical outburst from an active galactic nucleus (AGN; AT2019fdr). For the latter two sources, infrared follow-up observations revealed a powerful reverberation signal due to dust heated by the flare. This discovery motivates a systematic study of neutrino emission from all supermassive black hole with similar dust echoes. Because dust reprocessing is agnostic to the origin of the outburst, our work unifies TDEs and high-amplitude flares from AGN into a population that we dub accretion flares. Besides the two known events, we uncover a third flare that is coincident with a PeV-scale neutrino (AT2019aalc). Based solely on the optical and infrared properties, we estimate a significance of 3.6$σ$ for this association of high-energy neutrinos with three accretion flares. Our results imply that at least ~10% of the IceCube high-energy neutrino alerts could be due to accretion flares. This is surprising because the sum of the fluence of these flares is at least three orders of magnitude lower compared to the total fluence of normal AGN. It thus appears that the efficiency of high-energy neutrino production in accretion flares is increased compared to non-flaring AGN. We speculate that this can be explained by the high Eddington ratio of the flares.
format Preprint
id arxiv_https___arxiv_org_abs_2111_09391
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Establishing accretion flares from massive black holes as a source of high-energy neutrinos
van Velzen, Sjoert
Stein, Robert
Gilfanov, Marat
Kowalski, Marek
Hayasaki, Kimitake
Reusch, Simeon
Yao, Yuhan
Garrappa, Simone
Franckowiak, Anna
Gezari, Suvi
Nordin, Jakob
Fremling, Christoffer
Sharma, Yashvi
Yan, Lin
Kool, Erik C.
Stern, Daniel
Veres, Patrik M.
Sollerman, Jesper
Medvedev, Pavel
Sunyaev, Rashid
Bellm, Eric C.
Dekany, Richard G.
Duev, Dimitri A.
Graham, Matthew J.
Kasliwal, Mansi M.
Kulkarni, Shrinivas R.
Laher, Russ R.
Riddle, Reed L.
Rusholme, Ben
High Energy Astrophysical Phenomena
The origin of cosmic high-energy neutrinos remains largely unexplained. For high-energy neutrino alerts from IceCube, a coincidence with time-variable emission has been seen for three different types of accreting black holes: (1) a gamma-ray flare from a blazar (TXS 0506+056), (2) an optical transient following a stellar tidal disruption event (TDE; AT2019dsg), and (3) an optical outburst from an active galactic nucleus (AGN; AT2019fdr). For the latter two sources, infrared follow-up observations revealed a powerful reverberation signal due to dust heated by the flare. This discovery motivates a systematic study of neutrino emission from all supermassive black hole with similar dust echoes. Because dust reprocessing is agnostic to the origin of the outburst, our work unifies TDEs and high-amplitude flares from AGN into a population that we dub accretion flares. Besides the two known events, we uncover a third flare that is coincident with a PeV-scale neutrino (AT2019aalc). Based solely on the optical and infrared properties, we estimate a significance of 3.6$σ$ for this association of high-energy neutrinos with three accretion flares. Our results imply that at least ~10% of the IceCube high-energy neutrino alerts could be due to accretion flares. This is surprising because the sum of the fluence of these flares is at least three orders of magnitude lower compared to the total fluence of normal AGN. It thus appears that the efficiency of high-energy neutrino production in accretion flares is increased compared to non-flaring AGN. We speculate that this can be explained by the high Eddington ratio of the flares.
title Establishing accretion flares from massive black holes as a source of high-energy neutrinos
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2111.09391