TELAMON Radio Observations of Compact Radio Sources in the Overlap Field of IceCube220627A and IceCube220629A
ATel #15503; Matthias Kadler (JMU Wuerzburg), Petra Benke (MPIfR Bonn, JMU Wuerzburg), Florian Eppel (JMU Wuerzburg), Florian Roesch (JMU Wuerzburg) for the TELAMON team
on 6 Jul 2022; 08:28 UT
Credential Certification: Matthias Kadler (matthias.kadler@astro.uni-wuerzburg.de)
Subjects: Radio, Gamma Ray, Neutrinos, AGN, Blazar
On 2022-06-27 and 2022-06-29, the IceCube neutrino telescope detected two track-like events with a moderate probability of being of astrophysical origin, both selected by the ICECUBE_Astrotrack_BRONZE alert stream (GCN #32277, GCN #32299). These two events are remarkable because they are separated by only two days and the best-fit position of IceCube220629A fully falls within the 90% uncertainty region of IceCube-220627A, suggesting a possible joint astrophysical source. In order to search for correlated radio flaring activity from positionally coincident radio-cataloged blazars, we have observed all six compact radio sources listed in the Radio Fundamental Catalog (RFC; rfc_2021d_catalog) that are within the overlap region of IceCube220627A and IceCube220629A on July 01, 2022, in the 4.5cm band with the Effelsberg 100-m telescope: J1052+0457, J1055+0501, J1056+0517, J1058+0443, J1059+0517, and J1100+0444. All six sources are detected at flux densities near their historical (low-frequency) RFC levels.
On the same day, we also observed J1050+0432, which is associated with the known gamma-ray source 4FGL J1050.1+0432. This radio source is located slightly outside the 90% confidence region of IceCube220629A but still well within IC220627A. We detected J1050+0432 in the 4.5cm band with 298+-3mJy in the 4.5cm band and also with 325+-9mJy in the 2cm band. These values are well compatible with the common flux-density range for this source found in historical data bases like the RFC or NED. The possible doublet IceCube220627A/IceCube220629A can thus currently not be associated with any obvious flaring radio blazar.
The TELAMON program 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.
