THE JAMES CLERK MAXWELL TELESCOPE NEARBY GALAXIES LEGACY SURVEY. II. WARM MOLECULAR GAS AND STAR FORMATION IN THREE FIELD SPIRAL GALAXIES

Journal Article · Sat May 01 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/714/1/571· OSTI ID:21448894

Warren, B E; Wilson, C D; Sinukoff, E ^[1]; Israel, F P; Van der Werf, P P ^[2]; Serjeant, S ^[3]; Bendo, G J; Clements, D L ^[4]; Brinks, E ^[5]; Irwin, J A ^[6]; Knapen, J H ^[7]; Leech, J; Tan, B K ^[8]; Matthews, H E ^[9]; Muehle, S ^[10]; Mortimer, A M. J. ^[11]; Petitpas, G ^[12]; Spekkens, K ^[13]; Tilanus, R P. J. ^[14]; Usero, A ^[15]

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1. Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)
2. Sterrewacht Leiden, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)
3. Department of Physics and Astronomy, Open University, Milton Keynes, MK7 6AA (United Kingdom)
4. Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom)
5. Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom)
6. Department of Physics, Engineering Physics and Astronomy, Queen's University, Kingston, ON (Canada)
7. Instituto de Astrofisica de Canarias, E-38200 La Laguna (Spain)
8. Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)
9. National Research Council Canada, Herzberg Institute of Astrophysics, DRAO, P.O. Box 248, White Lake Road, Penticton, BC V2A 6J9 (Canada)
10. Joint Institute for VLBI in Europe, Postbus 2, 7990 AA Dwingeloo (Netherlands)
11. Scottish Universities Physics Alliance, Institute for Astronomy, Royal Observatory Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom)
12. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
13. Department of Physics, Royal Military College of Canada, P.O. Box 17000, Station Forces, Kingston, K7K 4B4 Ontario (Canada)
14. Joint Astronomy Centre, 660 North A'ohoku Place, Hilo, HI 96720 (United States)
15. Observatorio Astronomico Nacional, C/Alfonso XII 3, Madrid 28014 (Spain)

We present the results of large-area {sup 12}CO J = 3-2 emission mapping of three nearby field galaxies, NGC 628, NGC 3521, and NGC 3627, completed at the James Clerk Maxwell Telescope as part of the Nearby Galaxies Legacy Survey. These galaxies all have moderate to strong {sup 12}CO J = 3-2 detections over large areas of the fields observed by the survey, showing resolved structure and dynamics in their warm/dense molecular gas disks. All three galaxies were part of the Spitzer Infrared Nearby Galaxies Survey sample, and as such have excellent published multiwavelength ancillary data. These data sets allow us to examine the star formation properties, gas content, and dynamics of these galaxies on sub-kiloparsec scales. We find that the global gas depletion time for dense/warm molecular gas in these galaxies is consistent with other results for nearby spiral galaxies, indicating this may be independent of galaxy properties such as structures, gas compositions, and environments. Similar to the results from The H I Nearby Galaxy Survey, we do not see a correlation of the star formation efficiency with the gas surface density consistent with the Schmidt-Kennicutt law. Finally, we find that the star formation efficiency of the dense molecular gas traced by {sup 12}CO J = 3-2 is potentially flat or slightly declining as a function of molecular gas density, the {sup 12}CO J = 3-2/J = 1-0 ratio (in contrast to the correlation found in a previous study into the starburst galaxy M83), and the fraction of total gas in molecular form.

• OSTI ID: 21448894
• Journal Information: Astrophysical Journal, Vol. 714, Issue 1; Other Information: DOI: 10.1088/0004-637X/714/1/571; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
EMISSION
GALAXIES
MAPPING
STARS
TELESCOPES