Speaker
Description
We investigate the effect of azimuthal and axial ambient magnetic fields on the structure and evolution of a magnetized blast wave. The blast wave is driven by a central source of energy and forms a shell that results from the accumulation of interstellar matter behind the shock front. A similarity form of the ambient magnetic field is assumed to obtain self-similar solutions. The model is studied separately for both azimuthal and axial magnetic fields and applied to stellar wind bubbles and supernova remnants respectively using 1D numerical simulations. When the magnetic field is present, the forward shock front goes slower in the azimuthal case and faster in the axial one. For both tangential orientations, the thickness of the shell increases with the magnetic strength. In the azimuthal case, the thermal energy can be converted to magnetic energy near the inner boundary of the shell. Thus the temperature drops and the magnetic field increases at the tangential discontinuity of the stellar wind bubble. In the axial case of a supernova remnant, the numerical solution always follows a special curve in the parameter space given by the self-similar model.
