Discovery of a new faint radio SNR G108.2-0.6

¹ National Astronomical Observatories, CAS, Beijing 100012, PR China e-mail: wtian@ucalgary.ca
² Department of Physics & Astronomy, University of Calgary, Calgary, Alberta T2N 1N4, Canada
³ Department of Physics & Astronomy, Brandon University, Brandon, Manitoba R7A 6A9, Canada

Received: 14 December 2006
Accepted: 23 January 2007

Abstract

A new faint and large shell-type radio Supernova Remnant (SNR) G108.2-0.6 has been discovered in the Canadian Galactic Plane Survey (CGPS). The SNR shows an elliptical shell-type structure at 1420 MHz, and has a 408–1420 MHz TT-plot spectral index of α= -0.5±0.1 (ν), typical of a shell-type SNR. The remnant's flux density at 1420 MHz is 6.6±0.7 Jy, and at 408 MHz is 11.5±1.2 Jy. Both of these are corrected for compact sources. An integrated spectral index of -0.45±0.13 is determined. This new SNR has among the lowest surface brightness of any known remnants ( = 2.410^-22 W m^-2 Hz^-1 sr^-1). 21 cm Stokes Q and U CGPS data (plus preliminary Effelsberg Q and U maps) show some suggestive features that correlate with total power. observations show structures associated with G108.2-0.6 in the radial velocity range -53 to -58 km s^-1, and indicate it is located in the Perseus arm shock at a distance of 3.2±0.6 kpc. At this distance the diameter of G108.2-0.6 is 58 pc. IRAS maps (12, 25, 60 and 100 μm) of the new SNR show rich infrared emission surrounding G108.2-0.6.