Title: CO J=2-1 Observations toward the Supernova Remnant G54.1+0.3 Authors: Jung-Won Lee, Bon-Chul Koo, Jeong-Eun Lee
We present 12CO J = 2-1 line observations of G54.1+0.3, a composite supernova remnant with a mid-infrared (MIR) loop surrounding the central pulsar wind nebula (PWN). We mapped an area of 12' x 9' around the PWN and its associated MIR loop. We confirm two velocity components that had been proposed to be possibly interacting with the PWN/MIR-loop; the +53 km/s cloud that appears in contact with the eastern boundary of the PWN and the +23 km/s cloud that has CO emission coincident with the MIR loop. We have not found a direct evidence for the interaction in either of these clouds. Instead, we detected an 5'-long arc-like cloud at +15±23 km/s with a systematic velocity gradient of ~3 km/s/arcmin and broad-line emitting CO gas having widths (FWHM) of <7 km/s in the western interior of the supernova remnant. We discuss their association with the supernova remnant.
A new image from NASA's Chandra and Spitzer space telescopes shows the dusty remains of a collapsed star. The dust is flying past and engulfing a nearby family of stars. It shows the Chandra X-ray Observatory data in blue, and data from the Spitzer Space Telescope in green (shorter wavelength) and red-yellow (longer). The white source near the centre of the image is a dense, rapidly rotating neutron star, or pulsar, left behind after a core-collapse supernova explosion. The pulsar generates a wind of high-energy particles -- seen in the Chandra data -- that expands into the surrounding environment, illuminating the material ejected in the supernova explosion. Read more