Talks at the DAA. Talk by Sarka Wykes, from Harvard-Smithosonian Center for Astrophysics, Cambridge MS (USA). Place: Seminar of the Departament of Astronomy and Astrophysics, 4th floor of the Research Building, at Burjassot. Date: Tuesday, 19th of Setpember 2017. Time: 16:00.
Abstract:
Recently, it has become evident that X-ray jets are ubiquitous in low-power radio galaxies. In addition to diffuse X-ray emission, many of the jets feature compact X-ray brightness enhancements ('knots'). Their radio morphology is often similar, but not identical, to the X-ray morphology, and in some cases optical counterparts are observed as well. The issue of the knot origin(s) is yet undecided, although models exist suggesting that the knots with non-zero proper motion represent moving plasma packets while the knots without detected proper motions would originate from obstacles in the jet (stars and/or clouds) in interaction with the jet plasma flow. I will show some results from our 2D hydrodynamical simulations and analytical calculations of Centaurus A's jet interacting with winds of its internal, evolved stars, with a view to investigating the properties of shocks generated in these interactions and their match to the observed X-ray knots. The fate of the material released by the embedded stars, which is carried away by the jet at a rate of ~ 0.002 solar masses per year, will be also briefly addressed.
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