RADIO STRUCTURE OF THE REMNANT OF TYCHO SUPERNOVA (SN 1572)

The radio emission from the remnant of Tycho's supernova of 1572 arises in a nearly circular, clumpy shell. A very distinct, thin bright rim just outside the main shell can be seen around most of the periphery of the remnant. The outer edge of radio emission, usually defined by this bright rim, coincides perfectly with the outer x-ray boundary. Most of the emission is polarized by a modest amount, with the outer rim particularly prominent. We have used our observations at several wavelengths to map out the rotation measure at high angular resolution, and determine the intrinsic magnetic field direction. The magnetic field shows a somewhat cellular pattern but with a net radial orientation and a generally fairly low degree of polarization. There is no evidence for internal Faraday rotation or depolarization of the observed polarized emission from the remnant.