The SEDIGISM survey: First Data Release

The SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium) survey used the APEX telescope to map 84deg^2^ of the Galactic plane between l=-60{deg} and +31{deg} in several molecular transitions, including ^13^CO(2-1) and C^18^O(2-1), thus probing the moderately dense (~10^3^cm^-3^) component of the interstellar medium. With an angular resolution of 30arcsec and a typical 1{sigma} sensitivity of 0.8-1.0K at 0.25km/s velocity resolution, it gives access to a wide range of structures, from individual star-forming clumps to giant molecular clouds and complexes.

The coverage includes a good fraction of the first and fourth Galactic quadrants, allowing us to constrain the large-scale distribution of cold molecular gas in the inner Galaxy. In this paper, we provide an updated overview of the full survey and the data reduction procedures used. We also assess the quality of these data and describe the data products that are being made publicly available as part of this First Data Release (DR1).