J. L. Han, X. Y. Gao, X. H. Sun, W. Reich, L. Xiao, P. Reich, J. W. Xu, W. B. Shi, E. Fuerst, R. Wielebinski
We have observed 79 supernova remnants (SNRs) with the Urumqi 25m telescope at 6cm during the Sino-German 6cm polarization survey of the Galactic plane. We measured flux densities of SNRs at 6cm, some of which are the first measurements or the data at highest frequencies, so that we can determine or improve spectra of SNRs. Our observations have ruled out the suggested spectral breaks or spectral flattening of a few SNRs, and confirmed the spectral break of S147. Combined our 6cm maps with 11cm and 21cm maps from the Effelsberg 100m telescope, we calculated the spectral index maps of several large SNRs. For many remnants, we obtained for the first time polarization images, which show the intrinsic magnetic field structures at 6 cm. We disapproved three "remnants", OA184, G192.8-1.1 and G16.8-1.1, which show a thermal spectrum and no polarization. We have discovered two large supernova remnant, G178.2-4.2 and G25.1-2.3, from the 6cm survey maps.
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http://arxiv.org/abs/1304.1949
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