Parsec-scale properties of brightest cluster galaxies
Abstract
We present new VLBI observations at 5 GHz of a complete sample of brightest cluster galaxies (BCGs) in nearby Abell clusters (distance class <3). Combined with data from the literature, we provide parsec-scale information for 34 BCGs. Our analysis of the parsec-scale radio emission of BCGs and the cluster X-ray properties finds a possible dichotomy between BCGs in cool-core clusters and those in non-cool-core clusters. Among resolved sources, those in cool-core clusters tend to have two-sided parsec-scale jets, while those in less relaxed clusters have predominantly one-sided parsec-scale jets. We suggest that this difference is caused by the interplay between the jets and the surrounding medium. The one-sided structure in non-cool-core clusters may be due to Doppler boosting effects in relativistic, intrinsically symmetric jets whereas two-sided morphology in cool core clusters is probably related to the presence of heavy and mildly relativistic jets that have been decelerated on the parsec-scale. Evidence of recurrent activity is also found in BCGs in cool-core clusters.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- June 2010
- DOI:
- arXiv:
- arXiv:1002.1380
- Bibcode:
- 2010A&A...516A...1L
- Keywords:
-
- galaxies: clusters: general;
- galaxies: nuclei;
- galaxies: jets;
- galaxies: structure;
- radio continuum: galaxies;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 20 pages, 10 figures, accepted for publication in A&