The peculiar radio galaxy 4C 35.06: a case for recurrent AGN activity?
Abstract
Using observations obtained with the LOw Fequency ARray (LOFAR), the Westerbork Synthesis Radio Telescope (WSRT) and archival Very Large Array (VLA) data, we have traced the radio emission to large scales in the complex source 4C 35.06 located in the core of the galaxy cluster Abell 407. At higher spatial resolution (~4"), the source was known to have two inner radio lobes spanning 31 kpc and a diffuse, low-brightness extension running parallel to them, offset by about 11 kpc (in projection). At 62 MHz, we detect the radio emission of this structure extending out to 210 kpc. At 1.4 GHz and intermediate spatial resolution (~30"), the structure appears to have a helical morphology. We have derived the characteristics of the radio spectral index across the source. We show that the source morphology is most likely the result of at least two episodes of AGN activity separated by a dormant period of around 35 Myr. The AGN is hosted by one of the galaxies located in the cluster core of Abell 407. We propose that it is intermittently active as it moves in the dense environment in the cluster core. Using LOFAR, we can trace the relic plasma from that episode of activity out to greater distances from the core than ever before. Using the the WSRT, we detect HI in absorption against the center of the radio source. The absorption profile is relatively broad (FWHM of 288 km/s), similar to what is found in other clusters. Understanding the duty cycle of the radio emission as well as the triggering mechanism for starting (or restarting) the radio-loud activity can provide important constraints to quantify the impact of AGN feedback on galaxy evolution. The study of these mechanisms at low frequencies using morphological and spectral information promises to bring new important insights in this field.
Keywords
Cite
@article{arxiv.1504.06642,
title = {The peculiar radio galaxy 4C 35.06: a case for recurrent AGN activity?},
author = {A. Shulevski and R. Morganti and P. D. Barthel and M. Murgia and R. J. van Weeren and G. J. White and M. Brüggen and M. Kunert-Bajraszewska and M. Jamrozy and P. N. Best and H. J. A. Röttgering and K. T. Chyzy and F. de Gasperin and L. Bîrzan and G. Brunetti and M. Brienza and D. A. Rafferty and J. Anderson and R. Beck and A. Deller and P. Zarka and D. Schwarz and E. Mahony and E. Orrú and M. E. Bell and M. J. Bentum and G. Bernardi and A. Bonafede and F. Breitling and J. W. Broderick and H. R. Butcher and D. Carbone and B. Ciardi and E. de Geus and S. Duscha and J. Eislöffel and D. Engels and H. Falcke and R. A. Fallows and R. Fender and C. Ferrari and W. Frieswijk and M. A. Garrett and J. Grießmeier and A. W. Gunst and G. Heald and M. Hoeft and J. Hörandel and A. Horneffer and A. J. van der Horst and H. Intema and E. Juette and A. Karastergiou and V. I. Kondratiev and M. Kramer and M. Kuniyoshi and G. Kuper and P. Maat and G. Mann and R. McFadden and D. McKay-Bukowski and J. P. McKean and H. Meulman and D. D. Mulcahy and H. Munk and M. J. Norden and H. Paas and M. Pandey-Pommier and R. Pizzo and A. G. Polatidis and W. Reich and A. Rowlinson and A. M. M. Scaife and M. Serylak and J. Sluman and O. Smirnov and M. Steinmetz and J. Swinbank and M. Tagger and Y. Tang and C. Tasse and S. Thoudam and M. C. Toribio and R. Vermeulen and C. Vocks and R. A. M. J. Wijers and M. W. Wise and O. Wucknitz},
journal= {arXiv preprint arXiv:1504.06642},
year = {2015}
}
Comments
10 pages, 6 figures. Accepted to A&A