Published online by Cambridge University Press: 12 April 2016
Recent VLA observations of the shell supernova remnant SN 1006 AD (Reynolds and Gilmore 1986) and the Crablike remnant 3C 58 (SN 1181 AD?; Reynolds and Aller 1987) show features at high resolution that contain information on details of particle acceleration and transport in the remnants. Thin arcs at the edge of SN 1006 require time-variable particle acceleration and/or magnetic field amplification. Filaments in 3C 58 probably result from interaction of pulsar-generated relativistic fluid with filaments of thermal gas formed early in the remnant’s life by cooling or dynamical instabilities. Their sharp edges imply efficient scattering by Alfvén waves; as much as 1% of the large-scale magnetic energy density may be in magnetic turbulence on length scales of 1011 cm.