MHD Instabilities and Radio-Mode Feedback in Intracluster Medium

University Of Maryland, College Park, College Park MD

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Dr Bogdanovic and Dr Reynolds will conduct a series of 3-D magnetohydrodynamic simulations, to study how outflows from radio galaxies affect the surrounding gas, and to better understand the role of magnetic fields in regulating the temperature of the X-ray-emitting gas in galaxy clusters. First, they will study bubbles rising in a plane-parallel atmosphere. They will include both radiative cooling and heat transfer along magnetic fields in their simulations, to assess how these affect the magnetic field geometry and conductive heat flow. Simulating an entire galaxy cluster, they will examine whether the observed temperature structure in the gas might represent a balance between radiative cooling and heating as the radio jet blows bubbles in the cluster gas. Finally, Dr Bogdanovic and Dr Reynolds will consider galaxy clusters in a cosmological setting. They will examine how mergers between clusters, and galaxies stirring the gas, will affect the gas temperature by introducing additional turbulence and mixing. Targeted studies will examine in detail the effect of various transport processes: anisotropic viscosity, the diffusion of cosmic rays, and heat conduction. Dr Bogdanovic is a woman scientist at an early stage of her career. Heat transport by turbulence and thermal conduction is important for studies of terrestrial fusion plasmas. Each year, Dr Bogdanovic and Dr Reynolds will recruit an Astronomy graduate student to work on some aspect of this research for a short project (a required element of the PhD program), and an undergraduate to work on visualizing the results from the simulations. Both Dr Bogdanovic and Dr Reynolds will continue to give public talks on their work.