Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-29T06:58:42.889Z Has data issue: false hasContentIssue false

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

Published online by Cambridge University Press:  05 March 2013

Jürgen Ott*
Affiliation:
National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA California Institute of Technology, 1200 E. California Blvd., Caltech Astronomy 104-25, Pasadena, CA 91125-2400, USA
Tony Wong
Affiliation:
Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801, USA
Jorge L. Pineda
Affiliation:
Argelander Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
Annie Hughes
Affiliation:
Centre for Supercomputing and Astrophysics, Swinburne University of Technology, Hawthorn, VIC 3122, Australia CSIRO Australia Telescope National Facility, Cnr Vimiera & Pembroke Roads, Marsfield, NSW 2122, Australia
Erik Muller
Affiliation:
Centre for Supercomputing and Astrophysics, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
Zhi-Yun Li
Affiliation:
Department of Astronomy, University of Virginia, PO Box 400325, Charlottesville, VA 22903-4325, USA
Min Wang
Affiliation:
Purple Mountain Observatories, CAS, 2 West Beijing Road, Nanjing 210008, China
Lister Staveley-Smith
Affiliation:
School of Physics M013, University of Western Australia, Crawley, WA 6009, Australia
Yasuo Fukui
Affiliation:
Department of Astrophysics, Nagoya University, Furocho, Chikusaku, Nagoya 464-8602, Japan
Axel Weiß
Affiliation:
Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
Christian Henkel
Affiliation:
Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
Ulrich Klein
Affiliation:
Argelander Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
*
LCorresponding author. Email: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

With the ATNF Mopra telescope we are performing a survey in the 12CO(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 12CO(1–0) and Hi emission 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 H2 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.

Type
Research Article
Copyright
Copyright © Astronomical Society of Australia 2008

References

Bekki, K. & Chiba, M., 2007, PASA, 24, 21 CrossRefGoogle Scholar
Braun, J. M., Bomans, D. J., Will, J.-M. & de Boer, K. S., 1997, A&A, 328, 167 Google Scholar
Cappa, C., Niemela, V. S., Martín, M. C. & McClure-Griffiths, N. M., 2005, A&A, 436, 155 Google Scholar
Cohen, R. S., Dame, T. M., Garay, G., Montani, J., Rubio, M. & Thaddeus, P., 1988, ApJ, 331, L95 Google Scholar
Cohen, M., Staveley-Smith, L. & Green, A., 2003, MNRAS, 340, 275 Google Scholar
Connors, T. W., Kawata, D. & Gibson, B. K., 2006, MNRAS, 371, 108 Google Scholar
de Boer, K. S., Richter, P., Bomans, D. J., Heithausen, A. & Koorneef, J., 1998a, A&A, 338, L5 Google Scholar
de Boer, K. S., Braun, J. M., Vallenari, A. & Mebold, U., 1998b, A&A, 329, L49 Google Scholar
Dickey, J. M. & Lockman, F. J., 1990, ARA&A, 28, 215 Google Scholar
Fujimoto, M. & Noguchi, M., 1990, PASJ, 42, 505 Google Scholar
Fukui, Y. et al., 1999, PASJ, 51, 745 Google Scholar
Fukui, Y., 2007, in IAU Symposium 237, Triggered Star Formation in a Turbulent ISM, Eds. Elmergreen, B. G. & Palous, J., 31 Google Scholar
Gardiner, L. T., Sawa, T. & Fujimoto, M., 1994, MNRAS, 266, 567 Google Scholar
Gardiner, L. T., Turfus, C. & Putman, M. E., 1998, ApJ, 507, L35 Google Scholar
Imara, N. & Blitz, L., 2007, ApJ, 662, 969 CrossRefGoogle Scholar
Israel, F. P., 1997, A&A, 328, 471 Google Scholar
Johansson, L. E. B. et al., 1998, A&A, 331, 857 Google Scholar
Jones, T. J., Woodward, C. E., Boyer, M. L., Gehrz, R. D. & Polomski, E., 2005, ApJ, 620, 731 Google Scholar
Kim, S., Staveley-Smith, L., Dopita, M. A., Freeman, K. C., Sault, R. J., Kesteven, M. J. & McConnell, D., 1998, ApJ, 503, 674 Google Scholar
Kim, S. et al., 2007, ApJS, 171, 419 Google Scholar
Kutner, M. L. et al., 1997, A&AS, 122, 255 Google Scholar
Ladd, N., Purcell, C., Wong, T. & Robertson, S., 2005, PASA, 22, 62 Google Scholar
Luks, T. & Rohlfs, K., 1992, A&A, 263, 41 Google Scholar
Mastropietro, C., Moore, B., Mayer, L., Wadsley, J. & Stadel, J., 2005, MNRAS, 363, 509 CrossRefGoogle Scholar
Mizuno, N. et al., 2001, PASJ, 53, 971 Google Scholar
Murai, T. & Fujimoto, M., 1980, PASJ, 32, 581 Google Scholar
Nidever, D. L., Majewski, S. R. & Burton, W. B., 2008, ApJ, 679, 432 Google Scholar
Pineda, J. L., Ott, J., Klein, U., Wong, T., Muller, E. & Hughes, A., 2008, ApJ, submittedGoogle Scholar
Staveley-Smith, L., Kim, S., Calabretta, M. R., Haynes, R. F. & Kesteven, M. J., 2003, MNRAS, 339, 87 Google Scholar
Strong, A. W. et al., 1988, A&A, 207, 1 Google Scholar
Tumlinson, J. et al., 2002, ApJ, 566, 857 Google Scholar
van der Marel, R. P. & Cioni, M.-R. L., 2001, AJ, 122, 1807 Google Scholar
Walter, F. et al., 2007, ApJ, 661, 102 Google Scholar
Wong, T., Whiteoak, J. B., Ott, J., Chin, Y. & Cunningham, M. R., 2006, ApJ, 649, 224 Google Scholar
Yamaguchi, R., Mizuno, N., Onishi, T., Mizuno, A. & Fukui, Y., 2001, ApJL, 553, L185 Google Scholar