The Effect of Metallicity on Molecular Gas and Star Formation in the Large Magellanic Cloud
Abstract
The Magellanic Clouds provide the only laboratory to study the effect of metallicity on molecular gas and star formation at high resolution. We use the dust emission (Herschel 100, 160, 250, and 350 micron) to trace the total column of gas distribution and remove the HI gas leaving the molecular gas component distribution; we avoid the known biases of CO and reveal molecular gas with no bright CO emission. Relating the molecular gas to the star formation rate, traced by H-alpha and 24 micron, reveals an average molecular gas depletion time of ∼ 1 Gyr in the LMC. This is consistent with normal disk galaxies (∼ 2 Gyr; Bigiel et al. 2008, 2012) and the SMC (Bolatto et al. 2011), suggesting that metallicity does not strongly affect the galaxy-wide molecular gas star formation efficiency. We also contrast the metallicity-dependent predictions of the Ostriker, McKee, & Leroy (2011) and Krumholz, McKee, & Tumlinson (2009) models of star formation with the data.
- Publication:
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American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22311206J