Star Formation at the Periphery of a Molecular Superbubble: The Case of G12.79+0.43

Abstract

We present a multiwavelength investigation of the molecular cloud complex G12.79+0.43, which extends over $\sim 18^{\prime }$ on the sky. Several infrared- and radio-bright regions are arranged along an irregular rim, surrounding a central region characterised by diffuse 24~$\mu$m emission. CO molecular line observations reveal three prominent velocity components along the line of sight. Low-frequency radio continuum observations at 666 and 1300~MHz show diffuse emission spanning $\sim 10.5^{\prime }$ ($\sim$7.3~pc), predominantly filling the central region enclosed by the infrared-bright structures. We identify 70 compact radio sources and six \hii~regions across the cloud complex, which are likely powered by early B-type ZAMS stars. Using infrared data, we identify a total of 82 YSO candidates, including 28 Class~I sources, distributed across the cloud complex. On larger scales, the kinematics of the molecular gas over a $2^{\circ }\times 2^{\circ }$ field indicate that G12.79+0.43 is located along the rim of a larger molecular superbubble (diameter $\sim 50$~pc) that also encompasses the well-known W33 region. The inferred expansion age of this superbubble is $\sim 0.3$~Myr. While the spatial association between G12.79+0.43 and the superbubble is evident, the current data do not allow us to establish a clear causal connection between the superbubble evolution and the ongoing star formation within G12.79+0.43.

26 pages, 16 figures, 7 tables, Accepted for publication in the Astronomical Journal (AJ)

References in corpus (32)

• ATLASGAL --- properties of a complete sample of Galactic clumps
• Bias-free Measurement of Giant Molecular Cloud Properties
• On the Density Distribution in Star-forming Interstellar Clouds
• Intrinsically Red Sources observed by Spitzer in the Galactic Mid-Plane
• FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) I: Project Overview and Initial Results
• 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 ($-71.0^{\circ }<\ell <67.0^{\circ }$)
• IR Dust Bubbles: Probing the Detailed Structure and Young Massive Stellar Populations of Galactic HII Regions
• The Electron Temperature Gradient in the Galactic Disk
• Multi-temperature mapping of dust structures throughout the Galactic Plane using the PPMAP tool with Herschel Hi-GAL data
• A 24 Micron Point Source Catalog of the Galactic Plane from Spitzer/MIPSGAL
• Molecular clouds have power-law probability distribution functions
• SPICY: The Spitzer/IRAC Candidate YSO Catalog for the Inner Galactic Midplane
• The SEDIGISM survey: Molecular clouds in the inner Galaxy
• A Survey of OH Masers Towards High Mass Protostellar Objects
• PHANGS-JWST First Results: Multi-wavelength view of feedback-driven bubbles (The Phantom Voids) across NGC 628
• Understanding star formation in molecular clouds IV. Column density PDFs from quiescent to massive molecular clouds
• Herschel Observations of the W3 GMC: Clues to the Formation of Clusters of High-Mass Stars
• The Milky Way Project Second Data Release: Bubbles and Bow Shocks
• Quantifying the energetics of molecular superbubbles in PHANGS galaxies
• Establishing the evolutionary timescales of the massive star formation process through chemistry
• Evolution of the density PDF in star forming clouds: the role of gravity
• The "Carina Flare" Supershell: Probing the Atomic and Molecular ISM in a Galactic Chimney
• The SEDIGISM survey: a search for molecular outflows
• Observations of Cyanopolyynes toward Four High-Mass Star-Forming Regions Containing Hot Cores
• The first interferometric survey in the K-band of massive YSOs. On the hot dust, ionised gas, and binarity at au scales
• Probing the massive star forming environment - a multiwavelength investigation of the filamentary IRDC G333.73+0.37
• Star forming activity in the H II regions associated with IRAS 17160-3707 complex
• New detections of HC${}_5$N toward hot cores associated with 6.7 GHz methanol masers
• The new Herschel/PACS Point Source Catalogue
• Cloud-cloud collision and star formation in G013.313+0.193
• Galactic Superbubbles in 3D: Wind Formation and Cloud Shielding
• Low-velocity large-scale shocks in the infrared dark cloud G035.39-00.33: bubble-driven cloud-cloud collisions