TELAMON Detection of a High-State Compact Radio Source and Gamma-Bright AGN Positionally Coincident with Two IceCube Bronze Neutrino Events (IceCube-191231A  and IceCube-211125A)
Matthias Kadler (JMU Wuerzburg), Florian Eppel (JMU Wuerzburg), Jonas Hessdoerfer (JMU Wuerzburg), Philip Weber (JMU Wuerzburg), Jonas Sinapius (DESY), Raniere de Menezes (JMU Wuerzburg) for the TELAMON team
The TELAMON program (Kadler et al. 2021, Proc. ICRC 2021) is using the Effelsberg 100-m telescope of the MPIfR (Max-Planck-Institut fÃ¼r Radioastronomie) to monitor the radio spectra of active galactic nuclei (AGN) under scrutiny in astroparticle physics, namely TeV blazars and candidate neutrino-associated AGN.

We have observed all nine compact radio sources listed in the the rfc_2021c_catalog that are within 3 degree distance of the nominal position of the recently detected high-energy neutrino IceCube-211125A (GCN #31126) on Nov 28/29, 2021, at frequencies between 4.85GHz and 24.75GHz. Seven sources are detected at flux densities near their historical (low-frequency) RFC levels. We point out two sources that are noteworthy:

J0258+2030 is furthermore particularly noteworthy as it is associated with the Fermi-LAT gamma-ray source 4FGL J0258.1+2030 and also positionally coincident with an earlier IceCube bronze neutrino event (IceCube-191231A, see GCN # 26620). To our knowledge this is the first case of a gamma-ray bright AGN consistent with two IceCube neutrino bronze or gold events and the radio flare coincident with IceCube-211125A makes it a particularly promising possible association.
radio,gamma ray,tev,neutrinos,agn,blazar,request for observations