RADIO OBSERVATIONS OF THE X-RAY SUPERNOVA REMNANT G272.2-3.2

Citation
Ar. Duncan et al., RADIO OBSERVATIONS OF THE X-RAY SUPERNOVA REMNANT G272.2-3.2, Monthly Notices of the Royal Astronomical Society, 289(1), 1997, pp. 97-104
Citations number
15
Categorie Soggetti
Astronomy & Astrophysics
ISSN journal
00358711
Volume
289
Issue
1
Year of publication
1997
Pages
97 - 104
Database
ISI
SICI code
0035-8711(1997)289:1<97:ROOTXS>2.0.ZU;2-Q
Abstract
Radio continuum observations are presented for the recently discovered X-ray supernova remnant (SNR) G272.2 - 3.2. Radio emission from this SNR has never before been detected, We find this remnant to have a non -thermal radio spectral index of 0.55 +/- 0.15 (S proportional to lamb da(alpha)), and an almost circular appearance with a diameter of appro ximately 15 arcmin (in agreement with the X-ray size). High-resolution observations with the Australia Telescope Compact Array (ATCA) reveal the remnant to consist of a series of faint filaments and patches of emission, with a maximum surface brightness of 10 mJy beam area(-1) at 1.4 GHz, and a diffuse emisson component, This diffuse emission appea rs to be produced by shock-accelerated electrons, Modest spectral inde x variations are seen across the SNR, indicating that G272.2 - 3.2 con tains no significant thermal or plerionic component. Optical filaments in the region appear to align well with the radio 'blobs', whilst the X-ray enhancements show no correlation with the 'blobs', These correl ations are consistent with a somewhat higher age for the remnant than is derived from the X-ray data; perhaps 6 x 10(3) yr or so, Within the sensitivity of the observations no polarized emission was detected fr om G272.2 - 3.2, which is possibly indicative of a highly twisted magn etic field.