2013/01/10 by M. Perucho, Y. Y. Kovalev. P. E. Hardee, Perucho, M. +8
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #astro-ph.CO #astro-ph.HE
paper · pdf · doi:10.48550/arxiv.1301.2049
6 pages. Proceedings of the 11th EVN Symposium. Bordeaux (France), October 2012
openalex publication_date 2013/01/10 · arxiv created 2013/01/13 · arxiv updated 2013/01/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We make use of VLBI observations of the radio jet in the quasar S5 0836+710 at different frequencies and epochs to study its properties. The jet shows helical structure at all frequencies. The ridge-line of the emission in the jet coincides at all frequencies and epochs, within the errors. We conclude that the helicity is a real, physical structure. Small differences between epochs reveal wave-like motion of the ridge-line transversal to the jet propagation axis. These transversal motions are measured to be superluminal. This unphysical result could correspond to a possible small amplitude oscillation of the ridge-line at the radio-core and to large errors in the determination of the positions. In addition, higher resolution images at 15 GHz show that the ridge-line does not coincide exactly with the centre of the radio jet. At arc-second scales, this powerful jet shows non-collimated, irregular structure and a lack of a hot-spot. Following this collection of evidence, we conclude that the ridge-line could be related to a pressure maximum within the jet cross-section, associated with the observed helical pattern that could lead to jet disruption at longer scales. We discuss the implications regarding the nature of the instability and the jet flow itself.