Journal Article

VLBI Scrutiny of a New Neutrino-Blazar Multiwavelength-Flare Coincidence

Kirchner, D., Ros, E., Readhead, A. C. S., Nanci, C., Paraschos, G. F., Plavin, A., Fromm, C. M., Eppel, F., Rösch, F., Lister, M. L., Gokus, A., Edwards, P. G., Gómez, J. L., Ojha, R., Benke, P., Krichbaum, T. P., Stevens, J., Hämmerich, S., Kovalev, Y. Y., Weber, P., Kadler, M., Heßdörfer, J., Giroletti, M.

2022

Overview

In recent years, evidence has started piling up that some high-energy cosmic neutrinos can be associated with blazars in flaring states. On 2022 February 26, a new blazar-neutrino coincidence was reported: the track-like neutrino event IC220225A detected by IceCube is spatially coincident with the flat-spectrum radio quasar PKS 0215+015. Like previous associations, this source was found to be in a high optical and γ-ray state. Moreover, the source showed a bright radio outburst, which substantially increases the probability of a true physical association. We have performed six observations with the VLBA shortly after the neutrino event with a monthly cadence and are monitoring the source with the Effelsberg 100m-Telescope, and with the Australia Compact Telescope Array. Here, we present first results on the contemporary parsec-scale jet structure of PKS 0215+015 in total intensity and polarization to constrain possible physical processes leading to neutrino emission in blazars.

• Publisher: Cambridge University Press
• Subject: Astronomy / Blazars / Calibration / Collaboration / Contributed Paper / Neutrinos / Quasars / Telescopes