The Molecular Ridge Close to 30 Doradus in the Large Magellanic Cloud

J. Ott, T. Wong, J.L. Pineda, A. Hughes, E. Muller, Z-Y. Li, M. Wang, Lister Staveley-Smith, Y. Fukui, A. Weib, C. Henkel, U. Klein

    Research output: Contribution to journalArticle

    27 Citations (Scopus)

    Abstract

    With the ATNF Mopra telescope we are performing a survey in the (CO)-C-12(1-0) line to map the molecular gas in the Large Magellanic Cloud. For some regions we also obtained interferometric maps of the high density gas tracers HCO+ and HCN with the Australia Telescope Compact Array. Here we discuss the properties of the elongated molecular complex that stretches about 2 kpc southward from 30 Doradus. Our data suggest that the complex, which we refer to as the 'molecular ridge', is not a coherent feature but consists of many smaller clumps that share the same formation history. Likely triggers of molecular-cloud formation are shocks and shearing forces that are present in the surrounding south-eastern HI overdensity region, a region influenced by strong ram pressure and tidal forces. The molecular ridge is at the western edge of the the overdensity region where a bifurcated velocity structure transitions into a single disk velocity component. We find that the (CO)-C-12(1-0) and HIemission peaks in the molecular ridge are typically near each other but never coincide. A likely explanation is the conversion of warmer, low-opacity HI to colder, high-opacity HI from which H-2 subsequently forms. On smaller scales we find that very dense molecular gas, as traced by interferometric HCO+ and HCN maps, is associated with star formation along shocked filaments and with rims of expanding shell-like structures, both created by feedback from massive stars.
    Original languageEnglish
    Pages (from-to)129-137
    JournalPublications of the Astronomical Society of Australia
    Volume25
    Issue number3
    DOIs
    Publication statusPublished - 2008

      Fingerprint

    Cite this

    Ott, J., Wong, T., Pineda, J. L., Hughes, A., Muller, E., Li, Z-Y., ... Klein, U. (2008). The Molecular Ridge Close to 30 Doradus in the Large Magellanic Cloud. Publications of the Astronomical Society of Australia, 25(3), 129-137. https://doi.org/10.1071/AS07054