Out now: The second data release (DR2) of RACS-mid1 set of curated and combined images made from the 1493 tiles observed as part of RACS-mid1 at 1367.5 MHz (with 144 MHz bandwidth).
This release contains images of the tiles associated with RACS-mid1 survey convolved to a common resolution and mosaicked with neighbouring images to obtain near-uniform sensitivity images covering the sky up to declination +49 degrees. Released are the 1493 Stokes I total intensity images constructed in this manner, and the resulting source and component catalogue covering the region.
The RACS-mid catalogue features a total of 3,105,668 radio sources over the 36,200 square degrees covered by the survey. The second data release of the RACS-mid survey is described in a paper to appear in the Publications of the Astronomical Society of Australia, and available on arXiv here:https://arxiv.org/abs/2311.12369
This catalogue marks a major milestone in radio astronomy, mapping the entire southern sky in unprecedented detail and providing the best-ever combination of resolution and sensitivity using the ASKAP radio telescope.
The second data release surpasses the sensitivity of DR1 with the detection of even fainter radio sources, and providing a wealth of previously unseen objects. The accuracy of RACS-mid is enhanced through the selective peeling and accurate modelling of primary beam responses, reducing artifacts, and improving the survey’s data quality.
Combining RACS-low and RACS-mid gives us a first glimpse of radio ‘colour. with ASKAP. Ultimately, when combined with the upcoming RACS-high, this will help improve our understanding of the physical mechanisms behind the emissions.