A T N F    D a i l y    A s t r o n o m y    P i c t u r e

25th of September 2017
VLBI images of active galactic nuclei
(by Müller et al.)
TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry) is a multiwavelength project to monitor relativistic jets in active galactic nuclei (AGN) of the Southern Sky. In particular, TANAMI is targetting active galaxies which have been detected at gamma-ray energies by NASA's Fermi satellite. The team's second paper, containing high angular resolution images of the centres of 39 active galaxies, has recently been accepted for publication. TANAMI Very Long Baseline Interferometry (VLBI) observations at 8.4 GHz are made with Southern-Hemisphere radio telescopes located in Australia, Antarctica, Chile, New Zealand, and South Africa. The image above is of the relatively nearby galaxy PKS 1343-601, also known as Centaurus B. The brightest part of the radio image is at top left, and this the core of the galaxy, where the super-massive black hole (that powers the radio jet) resides. The jet appears in the image to be one-sided, however it is believed that it is intrinsically two-sided, with the visible jet directed close to our line of sight and the relativistic speed of the jet resulting in it being strongly boosted. In contrast, the other side is directed in the opposite direction and is strongly boosted in that direction, rendering it invisible at the sensitivity limit of this image. PKS 1343-601 is an example of a jet which contains some hotspots but which is otherwise continuous over its length, in contrast to the jets of other sources, as will be illustrated over the next few days.

More details are given in the pre-print of the paper by Müller et al.

<<   |   archive   |   about   |   today   *   ATNF   |   Parkes   |   ATCA   |   Mopra   |   VLBI   |   ASKAP   |   >>