Dr Bilal serving as Assistant Professor Physics department SSC at UMT Lahore
Monday, July 04, 2022Topic "Outflows from Galaxies"
Venue "Superior University Lahore Gold Campus Main Raiwind Road"
Organizers "ORIC Superior"
Date "30th May 2022 "
Plasma outflow against a gravitational potential is usually referred to as a thermal outflow in galaxies. If thermal gas comes under the influence of cosmic rays, then we refer to them as cosmic ray accompanied outflows. We present a very interesting dependence of the cosmic ray diffusion coefficient on waves (Alfven Waves) in the context of hydrodynamics. There are two possible classes of outflows depending upon the suitably defined sound speed. One is subsonic outflows and the other one is supersonic. In the given figure, we show how different velocity and pressure profiles behave under the same set of boundary conditions. Thermal outflow and cosmic ray accompanied outflow look very similar. Quasi-thermal outflow looks similar to the other two types near the base, but somewhere along the flow waves become decoupled from the thermal gas and the flow becomes pure thermal outflow. Furthermore, we add nonlinear Landau damping effects on the different outflow profiles. This result is published in Ramzan et al. (2020), ApJ, 905, 117.
