Parkes observations for project P1123 semester 2022APRS_01

ASKAP sensitivity decreases quickly on large scales dropping to zero at the minimum baseline scale. Projects EMU and POSSUM are thus hampered in studying large objects (e.g. SNR, nearby galaxies, galaxy clusters, AGNs, the Galactic diffuse emission). Combination with data from a large single-dish telescope is required. The project GMIMS aims to cover the band 300-1800 MHz to study the properties of the Galactic magneto-ionic medium and magnetic field thanks to its unique resolution and dynamic range in RM space. Only the lower and upper end of the band have been observed in the south limiting its capabilities. Here we propose to conduct a pilot for PEGASUS (POSSUM EMU GMIMS All Stokes UWL Survey), a spectropolarimetric survey to map the entire southern sky up to Dec=+20 deg with the Parkes Radio Telescope, in the frequency range 704-1440-MHz. The goal is to map the large-scale emission in Stokes I, Q, U to serve those three cutting-edge projects. PEGASUS will: provide the large angular scales that ASKAP misses enabling EMU and POSSUM to study large-scale objects; complete coverage of the GMIMS 300-1800 MHz band in the South, and significantly improve its capability to investigate the magnetic properties of the Milky Way. In this pilot we aim to demonstrate that ASKAP and single-dish data can be combined, and the scanning strategy can be realized. The target is a Galactic EMU-POSSUM commensal Pilot II field with extended SNRs.