Transverse motions in CSOs?

Abstract

The measurement of proper motions in CSOs is a powerful tool to determine the dynamical evolution of the newly born extragalactic radio sources. We observed 3 CSOs with the VLBA in 2004 and in 2006 to monitor changes in their structure and measure the separation velocity of the hot spots. It is important to increase the size of the samples of CSOs with measured expansion velocity to test the existance of frustrated objects, and put stringent constraints on the current models. We found for all the three objects observed a transverse motion of the hotspots, and we suggest as the more likey explanation a precession in the jet axis. This behaviour likely inhibits or at least slows down the radio source growth because the head of the hotspot continuously hits new regions of the ISM. Therefore these radio sources may represent an old population of GPS/CSOs.

4 pages, 3 figures. Accepted for publication in Astronomische Nachrichten

References in corpus (8)

• A complete sample of GHz-Peaked-Spectrum radio sources and its radio properties
• Proper Motions in Compact Symmetric Objects
• Dating COINS: Kinematic Ages for Compact Symmetric Objects
• On the evolution of young radio-loud AGN
• A new sample of faint Gigahertz Peaked Spectrum radio sources
• VLBA observations of GHz-Peaked-Spectrum radio sources at 15 GHz
• The B3-VLA CSS sample. II: VLBA images at 18 cm
• Optical identifications of High Frequency Peakers

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• Jetted subgalactic-size radio sources in merging galaxies -- A jet redirection scenario