by Nigel Maxted (UNSW)

The W28 supernova remnant complex in three images. The top left image shows the radio continuum emission ( red ) from electrons inside the W28 shell. The supernova remnant is interacting with molecular gas seen in CO(2-1) ( magenta contours ). The densest gas is traced by CS(1-0) ( green ) and corresponds to high energy gamma-ray emission ( cyan contours ), which strongly suggests that cosmic rays have been accelerated and are interacting in the region. On the right is a zoomed-in image of the molecular gas directly shocked by W28. In addition to shock-tracing SiO emission ( red ) at the border of thermal X-rays ( blue ) emitted by shock-heated gas, signatures of a shock may be present in multiple inversion transition lines of the NH ₃ molecule (one transition is shown in green). The bottom-left image is an illustration of a cosmic-ray diffusion scenario that is consistent with multi-wavelength observations of the W28 region. More detailed descriptions of images/results are presented in Maxted et al (2016, submitted).

Reference: Nigel Maxted, Gavin Rowell, Phoebe de Wilt, Michael Burton, Catherine Braiding, Andrew Walsh, Yasuo Fukui, Akiko Kawamura 2016, American Institute of Physics Conference Series, submitted ( astro-ph/1610-00865 ).