FUNA Lunch Talk:

John ZuHone

NASA Goddard Space Flight Center

Simulating Radio Minihalos in the Sloshing Cool Cores of Galaxy Clusters

April 11

12:10PM, Room 230, NRAO, Edgemont Road


A number of relaxed, cool-core galaxy clusters exhibit diffuse, steep-spectrum radio sources in their central regions, known as radio minihalos. It has been proposed that the relativistic electrons responsible for the emission are either lower-energy electrons that have been reaccelerated by turbulence, or secondary particles generated by hadronic interactions between cosmic ray protons and the thermal proton population. In either case, core gas sloshing is thought to play an important role, since a number of observations indicate that the minihalo emission is coincident with the volume enveloped by sloshing cold fronts, and because sloshing motions generate turbulence and amplify the magnetic field in the core region. I will present high-resolution MHD simulations of gas sloshing in a galaxy cluster coupled with subgrid simulations of relativistic electrons to test both the reacceleration and hadronic models for radio minihalos, highlighting the different predictions of the two models for the spatial extent of the minihalo as well as its spectrum.