Emission from Supernova Remnants. Thermal Bremsstrahlung in the Sedov-Taylor Phase

Calculations of total emission and isophotal contours due to thermal bremsstrahlung in the Sedov-Taylor phase of a supernova remnant have been carried out for two ages and two initial energies. The maximum surface brightness occurs inside the shock front, with the position of the maximum moving inward at higher frequencies. The thickness of the observed ring also increases with frequency. At radio frequencies, the surface brightness increases with age, but is independent of initial energy. The total brightness, however, is greater for greater initial energy at a given age due to the greater radius. A formula for scaling of the results is given. Subject headings: interstellar matter - shock waves - supernova remnants