Eric M. Jones

Radio emission from young supernova remnants. II: Evolution and dependence on characteristics of the progenitor and the external medium

During the evolution of a supernova remnant (SNR), some of the explosion energy is converted to relativistic electron energy at the shock front; and, to the extent that the circumstellar medium (CSM) is clumpy, turbulent dynamo processes associated with the growth of Rayleigh-Taylor (R-T) fingers convert explosion kinetic energy into magnetic field energy. Phenomenological descriptions of these processes have been incorporated into a one-dimensional, spherical hydrodynamics program. Input parameters used in the calculations included the explosion energy, the mean CSM density, and various characteristics of the clump CSM

Buoyant supernova remnants

It is proposed that the time scale for buoyant rise may be about ore they lose their identify. Six SNRs from the lists of Shaver and Goss appear to be in the process of forming into toroids. The dominant gravitational term causing the rise appears to be fairly local inhomogeneities in the galactic gravitational field. A two-dimensional hydrodynamic calculation of a 4x10/sup 49/ erg supenova event is presented. (auth)

Radio Emission from Young Supernova Remnants: Effects of an Inhomogeneous Circumstellar Medium

The evolution of young supernova remnants has been modeled using a one-dimensional hydrodynamics code. Rayleigh-Taylor instabilities and the growth of Rayleigh-Taylor fingers have been included in the code. Turbulent dynamo amplification of magnetic fields and both turbulent and shock acceleration of relativistic electrons have been included macroscopically. From this, the distribution of synchrotron luminosity in the remnant has been calculated. It is found that the radio morphology of model remnants expanding into a homogeneous medium does not agree with observations. Expansion into a circumstellar medium with many small cloudlets does produce radio shells which agree with observations. It is suggested that supernova remnants reflect the interaction of ejected matter with a cloudy circumstellar medium.