Structure, Excitation, and Dynamics of the Inner Galactic Interstellar Medium (SEDIGISM)

The SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium) survey is an APEX 12-m telescope programme designed to map molecular gas in the inner Milky Way. The survey covers about 84 deg² of the southern Galactic plane, with continuous coverage from −60° ≤ l ≤ +17° at |b| ≤ 0.5°, and an additional 2 deg² region between +29° and +31° (W43) for comparison with northern surveys. The latitude range is extended in selected regions, reaching |b| ≤ 1° towards the Central Molecular Zone, b ≤ +0.75° towards RCW 120, and b ≤ −0.75° towards the Nessie filament. The primary data products are 13CO(2–1) and C18O(2–1) spectral cubes, complemented by additional transitions including CH3OH, H2CO, HC3N, HNCO, SiO, SO2, and SO. The dataset comprises 78 FITS cubes, each covering about 2° × 1° with 1° overlap, sampled at 9.5” pixels, 30” angular resolution, and 0.25 km/s velocity resolution (0.5 km/s for ancillary lines). The typical sensitivity is 0.8–1.0 K per channel (Tmb scale). The release includes fully calibrated spectral cubes and corresponding white-light integrated intensity maps.