# The Mopra Southern Galactic Plane CO Survey - Data Release 3

## TL;DR

This paper presents a comprehensive data release of the Mopra Southern Galactic Plane CO survey, providing high-resolution molecular gas observations across a significant region of the southern Milky Way, including maps, spectra, and a preliminary clump catalogue.

## Contribution

The paper introduces the third data release of the Mopra CO survey, offering detailed molecular gas data with unprecedented resolution and coverage of the Southern Galactic Plane.

## Key findings

- Velocity-integrated maps reveal Galactic arm structures.
- Gas mass estimates of approximately 10^6 solar masses per square degree.
- Preliminary catalogue of C18O clumps between l=330-340 degrees.

## Abstract

We present observations of fifty square degrees of the Mopra carbon monoxide (CO) survey of the Southern Galactic Plane, covering Galactic longitudes $l = 300$-$350^\circ$ and latitudes $|b| \le 0.5^\circ$. These data have been taken at 0.6 arcminute spatial resolution and 0.1 km/s spectral resolution, providing an unprecedented view of the molecular clouds and gas of the Southern Galactic Plane in the 109-115 GHz $J = 1$-0 transitions of $^{12}$CO, $^{13}$CO, C$^{18}$O and C$^{17}$O. We present a series of velocity-integrated maps, spectra and position-velocity plots that illustrate Galactic arm structures and trace masses on the order of $\sim$10$^{6}$ M$_{\odot}$ per square degree; and include a preliminary catalogue of C$^{18}$O clumps located between $l=330$-$340^\circ$. Together with information about the noise statistics of the survey these data can be retrieved from the Mopra CO website, the PASA data store and the Harvard Dataverse (doi:10.7910/DVN/LH3BDN ).