Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs

Details Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs

2005-04-19

arxiv.org/abs/astro-ph/0504412v1

Astrophys.J. 630 (2005) 269-279; Erratum-ibid. 642 (2006) 616

Astronomy and Astrophysics

Astrophysics

15 Pages, 2 figures, Accepted for Publication in ApJ

Scientific paper

10.1086/431171

The role of star formation in luminous and ultraluminous infrared galaxies is a hotly debated issue: while it is clear that starbursts play a large role in powering the IR luminosity in these galaxies, the relative importance of possible enshrouded AGNs is unknown. It is therefore important to better understand the role of star forming gas in contributing to the infrared luminosity in IR-bright galaxies. The J=3 level of 12CO lies 33K above ground and has a critical density of ~1.5 X 10^4 cm^-3. The 12CO(J=3-2) line serves as an effective tracer for warm-dense molecular gas heated by active star formation. Here we report on 12CO (J=3-2) observations of 17 starburst spirals, LIRGs and ULIRGs which we obtained with the Heinrich Hertz Submillimeter Telescope on Mt. Graham, Arizona. Our main results are the following: 1. We find a nearly linear relation between the infrared luminosity and warm-dense molecular gas such that the infrared luminosity increases as the warm-dense molecular gas to the power 0.92; We interpret this to be roughly consistent with the recent results of Gao & Solomon (2004a,b). 2. We find L_IR/M_H2 ratios ranging from ~10 to ~128 L_sun/M_sun using a standard CO-H2 conversion factor of 3 X 10^20 cm^-2 (K km s^-1)^-1. If this conversion factor is ~an order of magnitude less, as suggested in a recent statistical survey (Yao et al. 2003), then 2-3 of our objects may have significant contributions to the L_IR by dust-enshrouded AGNs.

Affiliated with

Also associated with

No associations

Rating

Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Warm-Dense Molecular Gas in the ISM of Starbursts, LIRGs and ULIRGs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-40356