The Mopra Southern Galactic Plane CO Survey—Data Release 3

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 • and latitudes |b| ≤ 0.5 • . These data have been taken at 0.6 arcminute spatial resolution and 0.1 km s −1 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 ∼10 6 M per square degree; and include a preliminary catalogue of C 18 O clumps located between l = 330-340 • . 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.

Radio observations of supernova remnant G1.9+0.3

“…To complement our ATCA data, we examined preliminary 12 CO(1-0) and 13 CO(1-0) data from the Mopra Southern Galactic Plane CO Survey (Burton et al 2013), taken between 2013 and 2018 by the 22-m Mopra radio telescope, located in the Warrambungles National Park, Australia. The full survey data release will cover longitudes of −110 • < l <11 • and latitudes of |b| < 1 • , with extensions in selected regions of interest (Braiding et al 2018). The full survey also includes the C 18 O(1-0) and C 17 O(1-0) isotopo-logue transitions, however these were not available for this investigation.…”

The G332 molecular cloud ring: I. Morphology and physical characteristics

“…The CO lines come from the isotopologue survey of 12 CO, 13 CO, and C 18 O, J = 1 → 0 transition lines (30 arcsec pixel size and ∼0.1 km s −1 spectral resolution), obtained using the 22 m single dish Mopra millimeter wave telescope, part of the Mopra Southern Galactic Plane CO Survey of the Milky Way (Burton et al , 2014Braiding et al 2015;Rebolledo et al 2016;Blackwell, Burton & Rowell 2017;Braiding et al 2018). In this survey we used the fast-on-the-fly mapping that maps the four CO isotopologues at the same time, taking 8 × 256 ms samples each cycle (2.048 s).…”

“…In order to investigate the highest column density clumps within the molecular ring, we decomposed it applying the CLUMPFIND algorithm (Williams, de Geus & Blitz 1994) to the C 18 O emission cube, binned and smoothed in the same way as in moment maps computation (see Section 5.1). We limited our analysis to the ring velocity range; however an expansion of this work, performed on 10 • of the Galactic Plane binned C 18 O datacube, is presented in Braiding et al (2018). After a series of tests we selected the value of 0.35 K, equivalent to 3.5σ , for both input parameters inc and low.…”

“…We used data from the Mopra Southern Galactic Plane CO Survey of the 12 CO, 13 CO, and C 18 O J = 1 → 0 transition lines (Braiding et al 2018) to perform a morphological and a physical characterization of a GMC (G332 molecular ring) sited in the G332 region of the Galactic plane. The CO emission peaks at V LSR = −50 km s −1 , which is equal to a distance of ∼3.3 kpc from the Sun (assuming correct a near distance solution for KDA) and to a Galactocentric distance of ∼5.5 kpc.…”

“…In the analysis performed in this paper, we will examine in detail the general physical characteristics and the morphology of a GMC recently discovered in the G332 region of the Galactic Plane, identified using data from the Mopra CO Southern Galactic Plane Survey (Braiding et al 2018).…”