The MUSTANG-2 Galactic Plane Survey (MGPS90) pilot

Abstract

We report the results of a pilot program for a Green Bank Telescope (GBT) MUSTANG Galactic Plane survey at 3 mm (90 GHz), MGPS90. The survey achieves a typical $1\sigma$ depth of $1-2$ mJy beam${}^{-1}$ with a 9" beam. We describe the survey parameters, quality assessment process, cataloging, and comparison with other data sets. We have identified 709 sources over seven observed fields selecting some of the most prominent millimeter-bright regions between $0°<\ell <50°$ (total area $\approx 7.5{°}^2$). The majority of these sources have counterparts at other wavelengths. By applying flux selection criteria to these sources, we successfully recovered several known hypercompact HII (HCHII) regions, but did not confirm any new ones. We identify 126 sources that have mm-wavelength counterparts but do not have cm-wavelength counterparts and are therefore candidate HCHII regions; of these, 10 are morphologically compact and are strong candidates for new HCHII regions. Given the limited number of candidates in the extended area in this survey compared to the relatively large numbers seen in protoclusters W51 and W49, it appears that most HCHII regions exist within dense protoclusters. Comparing the counts of HCHII to ultracompact HII (UCHII) regions, we infer the HCHII region lifetime is 16-46% that of the UCHII region lifetime. We additionally separated the 3 mm emission into dust and free-free emission by comparing with archival 870 $\mu$m and 20 cm data. In the selected pilot fields, most ($\gtrsim 80$%) of the 3 mm emission comes from plasma, either through free-free or synchrotron emission.

Accepted to ApJS. Data publicly released, with links in paper. Reposted to fix missing figure labels

References in corpus (8)

• ATLASGAL --- towards a complete sample of massive star forming clumps
• Properties of Hi-GAL clumps in the inner Galaxy]{The Hi-GAL compact source catalogue. I. The physical properties of the clumps in the inner Galaxy ($-71.0^{\circ }<\ell <67.0^{\circ }$)
• A 24 Micron Point Source Catalog of the Galactic Plane from Spitzer/MIPSGAL
• The Bolocam Galactic Plane Survey IV: 1.1 and 0.35 mm Dust Continuum Emission in the Galactic Center Region
• Thermal Feedback in the high-mass star and cluster forming region W51
• First release of the IPHAS Catalogue of New Extended Planetary Nebulae
• GLOSTAR -- Radio Source Catalog I: $28^{\circ }<\text{l}<36^{\circ }$ and $|b|<1^{\circ }$
• Fourier Plane Image Combination by Feathering

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