TELAMON: Effelsberg Monitoring of AGN Jets with Very-High-Energy Astroparticle Emissions

M. Kadler; U. Bach; D. Berge; S. Buson; D. Dorner; P. G. Edwards; F. Eppel; M. Giroletti; A. Gokus; O. Hervet; J. Heßdörfer; S. Koyama; A. Kraus; T. P. Krichbaum; E. Lindfors; K. Mannheim; R. de Menezes; R. Ojha; G. F. Paraschos; E. Pueschel; F. Rösch; E. Ros; B. Schleicher; J. Sinapius; J. Sitarek; J. Wilms; M. Zacharias

arXiv · 2108.00383

TELAMON: Effelsberg Monitoring of AGN Jets with Very-High-Energy Astroparticle Emissions

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Abstract

We introduce the TELAMON program, which is using the Effelsberg 100-m telescope to monitor the radio spectra of active galactic nuclei (AGN) under scrutiny in astroparticle physics, namely TeV blazars and candidate neutrino-associated AGN. Thanks to its large dish aperture and sensitive instrumentation, the Effelsberg telescope can yield radio data superior over other programs in the low flux-density regime down to several 10 mJy. This is a particular strength in the case of TeV-emitting blazars, which are often comparatively faint radio sources of the high-synchrotron peaked type. We perform high-cadence high-frequency observations every 2-4 weeks at multiple frequencies up to 44 GHz. This setup is well suited to trace dynamical processes in the compact parsec-scale jets of blazars related to high-energy flares or neutrino detections. Our sample currently covers about 40 sources and puts its focus on AGN with very-high-energy astroparticle emission, i.e., TeV blazars and neutrino-associated AGN. Here, we introduce the TELAMON program characteristics and present first results obtained since fall 2020.

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M. Kadler, U. Bach, D. Berge, S. Buson, D. Dorner, P. G. Edwards, F. Eppel, M. Giroletti, A. Gokus, O. Hervet, J. Heßdörfer, S. Koyama, A. Kraus, T. P. Krichbaum, E. Lindfors, K. Mannheim, R. de Menezes, R. Ojha, G. F. Paraschos, E. Pueschel, F. Rösch, E. Ros, B. Schleicher, J. Sinapius, J. Sitarek, J. Wilms, M. Zacharias. 2021-08-01. TELAMON: Effelsberg Monitoring of AGN Jets with Very-High-Energy Astroparticle Emissions. https://arxiv.org/abs/2108.00383

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