Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-25T16:22:42.381Z Has data issue: false hasContentIssue false

Gas, Dust and Star Formation in Nearby Galaxies as Seen with the JCMT

Published online by Cambridge University Press:  21 March 2013

José Ramón Sánchez-Gallego*
Affiliation:
Instituto de Astrofísica de Canarias, E-38205, La Laguna, Tenerife, Spain Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain 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.

We combine 12CO J = 3 − 2 for 155 nearby galaxies, obtained as part of the James Clerk Maxwell Telescope (JCMT) Nearby Galaxies Legacy Survey (NGLS), with star formation rates derived from Hα luminosities to probe the relation between warm, dense gas and star formation. These data are compared with ancillary data from the literature, including infrared (IR) and 1.4 GHz radio continuum luminosities and Hi masses. We find a good correlation between CO J = 3 − 2 luminosities and Hα-derived star formation rates (SFRs), which is in agreement with previous studies. Several groups of galaxies show a peculiar behaviour in the SFR(Hα) − LCOJ = 3 − 2 plot, which disappears when using IR data. We analyse these regions and propose several hypotheses to explain this behaviour, including group interactions and very recent (≲20 Myr) bursts of star formation only traced by Hα emission. While atomic hydrogen is hardly related with SFR, molecular and total gas (Hi + H2) show similar correlations with Hα luminosities. No correlation is found between CO J = 3−2 luminosity and metallicity, although galaxies with low metallicity are more likely to not be detected. We discuss that CO J = 3 − 2 does not seem to be a significantly better tracer of the star-forming gas, but its independence from metallicity may be used to constrain the conversion factor between CO and H2.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2013

References

Alonso, O., García-Dabó, C. E., Zamorano, J., Gallego, J., & Rego, M. 1999, ApJS, 122, 415CrossRefGoogle Scholar
Bendo, G. J., Wilson, C. D., Warren, B. E., et al. 2010, MNRAS, 402, 1409CrossRefGoogle Scholar
Corbelli, E., Bianchi, S., Cortese, L., et al. 2012, A&A, 542, A32Google Scholar
Dempsey, J. T., Holland, W. S., Chrysostomou, A., et al. 2012, ArXiv e-prints (1208.4622)Google Scholar
Gallego, J., Zamorano, J., Aragon-Salamanca, A., & Rego, M. 1995, ApJL, 455, L1Google Scholar
Hopkins, A. M., Connolly, A. J., & Szalay, A. S. 2000, AJ, 120, 2843CrossRefGoogle Scholar
Iono, D., Wilson, C. D., Yun, M. S., et al. 2009, ApJ, 695, 1537CrossRefGoogle Scholar
Irwin, J. A., Wilson, C. D., Wiegert, T., et al. 2011, MNRAS, 410, 1423Google Scholar
James, P. A., Shane, N. S., Beckman, J. E., et al. 2004, A&A, 414, 23Google Scholar
Kennicutt, R. C. Jr. & Kent, S. M. 1983, AJ, 88, 1094CrossRefGoogle Scholar
Kennicutt, R. C., Armus, L., Bendo, G., et al. 2003, Publ. Astron. Soc. Pac., 115, 928CrossRefGoogle Scholar
Kennicutt, R. C. Jr., Lee, J. C., Funes, José G. S. J., Sakai, S., & Akiyama, S. 2008, ApJS, 178, 247CrossRefGoogle Scholar
Knapen, J. H., Stedman, S., Bramich, D. M., Folkes, S. L., & Bradley, T. R. 2004, A&A, 426, 1135Google Scholar
Lanzetta, K. M., Yahata, N., Pascarelle, S., Chen, H.-W., & Fernández-Soto, A. 2002, ApJ, 570, 492CrossRefGoogle Scholar
Madau, P., Ferguson, H. C., Dickinson, M. E., et al. 1996, MNRAS, 283, 1388CrossRefGoogle Scholar
Nagamine, K., Ostriker, J. P., Fukugita, M., & Cen, R. 2006, ApJ, 653, 881CrossRefGoogle Scholar
Paturel, G., Petit, C., Prugniel, P., et al. 2003, A&A, 412, 45Google Scholar
Sánchez-Gallego, J. R., Knapen, J. H., Heiner, J. S., et al. 2011, A&A, 527, A16Google Scholar
Sánchez-Gallego, J. R., Knapen, J. H., Wilson, C. D., et al. 2012, MNRAS, 422, 3208CrossRefGoogle Scholar
Scoville, N. Z., Polletta, M., Ewald, S., et al. 2001, AJ, 122, 3017Google Scholar
Schruba, A., Leroy, A. K., Walter, F., et al. 2012, AJ, 143, 138Google Scholar
Warren, B. E., Wilson, C. D., Israel, F. P., et al. 2010, ApJ, 714, 571Google Scholar
Wilson, C. D., Warren, B. E., Israel, F. P., et al. 2009, ApJ, 693, 1736CrossRefGoogle Scholar
Wilson, C. D., Warren, B. E., Israel, F. P., et al. 2012, MNRAS, 424, 3050CrossRefGoogle Scholar