CO observations of gas near the galactic supernova remnants G5.4-1.2, G5.55+0.32 and G5.71-0.08 *,**
National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA e-mail: firstname.lastname@example.org
Accepted: 13 October 2009
Aims. We searched for signs of interaction of radio supernova remnants with ambient molecular gas in the sky field just West of the SNR W28.
Methods. We analyze a datacube of CO emission having 1′ and 1.2 km s-1 resolution, made with on-the-fly mapping over the region o.
Results. Although broad CO lines characteristic of shocked gas were not seen in this kinematically complex region, a bright (14 K), new, marginally-resolved km s-1 outflow source G5.638+0.233 and a comparably bright rim of CO emission were found at/around the periphery of SNR G5.55+0.12. Most of the periphery of SNR G5.71-0.08 is surrounded by a bright rim of CO emission. CO emission at the 7 km s-1 velocity of a 1720 OH maser spot near SNR G5.70-0.12 is very bright, 19 K, but gas at -21 km s-1 is widespread over the region and CO emission is rather weak toward the OH maser spots at this velocity north of G5.4-1.2. Other very bright CO lines in the region are associated with H II regions, i.e. 27 K toward W28A2 = G5.89-0.39 and 15 K toward an MSX-IR source at o, o which is probably the exciting agent of a separate, classical HII region just north of W28A2.
Key words: ISM: clouds / ISM: molecules / HII regions
© ESO, 2009