Journal Article

PUBDB-2024-00291

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png TELAMON: Effelsberg monitoring of AGN jets with very-high-energy astroparticle emission -- I. Program description and sample characterization

Eppel, F. (Corresponding author) ; Kadler, M. ; Heßdörfer, J. ; Benke, P. ; Debbrecht, L. ; Eich, J. ; Gokus, A. ; Hämmerich, S. ; Kirchner, D. ; Paraschos, G. F. ; Rösch, F. ; Schulga, W. ; Sinapius, J.DESY* ; Weber, P. ; Bach, U. ; Dorner, D. ; Edwards, P. G. ; Giroletti, M. ; Kraus, A. ; Hervet, O. ; Koyama, S. ; Krichbaum, T. P. ; Mannheim, K. ; Ros, E. ; Zacharias, M. ; Zensus, J. A.

2024
EDP Sciences Les Ulis

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Please use a persistent id in citations: doi:10.1051/0004-6361/202348262  doi:10.3204/PUBDB-2024-00291

Report No.: arXiv:2401.06296

Abstract: Aims. 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, specifically TeV blazars and candidate neutrino-associated AGN. Here, we present and characterize our main sample of TeV-detected blazars. Methods. We analyze the data sample from the first ~2.5 years of observations between August 2020 and February 2023 in the range from 14 GHz to 45 GHz. During this pilot phase, we have observed all 59 TeV-detected blazars in the Northern Hemisphere (i.e., Dec. >0{\deg}) known at the time of observation. We discuss the basic data reduction and calibration procedures used for all TELAMON data and introduce a sub-band averaging method used to calculate average light curves for the sources in our sample. Results. The TeV-selected sources in our sample exhibit a median flux density of 0.12 Jy at 20 mm, 0.20 Jy at 14 mm and 0.60 Jy at 7 mm. The spectrum for most of the sources is consistent with a flat radio spectrum and we find a median spectral index ($S(\nu)\propto\nu^\alpha$) of $\alpha=-0.11$. Our results on flux density and spectral index are consistent with previous studies of TeV-selected blazars. Compared to the GeV-selected F-GAMMA sample, TELAMON sources are significantly fainter in the radio band. This is consistent with the double-humped spectrum of blazars being shifted towards higher frequencies for TeV-emitters (in particular for high-synchrotron peaked BL Lac type objects), which results in a lower radio flux density. The spectral index distribution of our TeV-selected blazar sample is not significantly different from the GeV-selected F-GAMMA sample. Moreover, we present a strategy to track the light curve evolution of sources in our sample for future variability and correlation analysis.

Note: 16 pages, 11 figures, 4 tables, accepted for publication in A&A

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Contributing Institute(s):

1. Gammaastronomie (Z_GA)

Research Program(s):

1. 613 - Matter and Radiation from the Universe (POF4-613) (POF4-613)
2. DFG project 447572188 - VLBA Beobachtungen von Neutrino-Kandidaten Blazaren (447572188) (447572188)
3. DFG project G:(GEPRIS)434448349 - TANAMI 2 – VLBI und Multiwellenlängen-Beobachtungen von AGN Jets des Südlichen Himmels (434448349) (434448349)
4. DFG project G:(GEPRIS)465409577 - Radioüberwachung und hochauflösende Bildgebung von extremen Blazaren und anderen TeV-detektierten aktiven Galaxien mit dem Effelsberg 100-m Teleskop und dem Global Millimetre VLBI Array (465409577) (465409577)
5. M2FINDERS - Mapping Magnetic Fields with INterferometry Down to Event hoRizon Scales (101018682) (101018682)

Experiment(s):

1. Measurement at external facility

Appears in the scientific report 2024

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Database coverage:
; ; ; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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Linked articles:

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Preprint Eppel, F. (Corresponding author) ; Kadler, M. ; Heßdörfer, J. ; Benke, P. ; Debbrecht, L. ; Eich, J. ; Gokus, A. ; Hämmerich, S. ; Kirchner, D. ; Paraschos, G. F. ; Rösch, F. ; Schulga, W. ; Sinapius, J.DESY* ; Weber, P. ; Bach, U. ; Dorner, D. ; Edwards, P. G. ; Giroletti, M. ; Kraus, A. ; Hervet, O. ; Koyama, S. ; Krichbaum, T. P. ; Mannheim, K. ; Ros, E. ; Zacharias, M. ; Zensus, J. A.
TELAMON: Effelsberg monitoring of AGN jets with very-high-energy astroparticle emission - I. Program description and sample characterization
[10.3204/PUBDB-2024-06546]     Files  Fulltext by arXiv.org BibTeX | EndNote: XML, Text | RIS

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