Triggered TELAMON Radio Observations of Compact Radio Sources in the Field of IceCube-211123A
ATel #15075; Matthias Kadler (JMU Wuerzburg), Florian Eppel (JMU Wuerzburg), Jonas Hessdoerfer (JMU Wuerzburg), Philip Weber (JMU Wuerzburg), Jonas Sinapius (DESY) for the TELAMON Team
on 29 Nov 2021; 19:29 UT
Credential Certification: Matthias Kadler (matthias.kadler@astro.uni-wuerzburg.de)
Subjects: Radio, Gamma Ray, >GeV, TeV, VHE, Neutrinos, Request for Observations, AGN, Blazar
The TELAMON program (Kadler et al. 2021, Proc. ICRC 2021) is using the Effelsberg 100-m telescope of the MPIfR (Max-Planck-Institut fuer 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 at maximum brightness of 100mJy or higher in the rfc_2021c_catalog that are positionally coincident with the recently detected high-energy neutrino IceCube-211123A (GCN #31110) on Nov 28, 2021, in the 2cm band (14GHz - 16GHz). All sources are detected at flux densities near their historical (low-frequency) RFC levels. None of them exceeds the historical maximum. The by far brightest source is J1751+0938 (PKS1749+096), which is also associated with a GeV and TeV gamma-ray source. It has been in a rather low radio state for several months recently. We found an inverted spectrum at ~2.5Jy at 14.25GHz and 2.7Jy at 16.75GHz with a spectral index of about +0.5 indicating high-frequency activity.
