[CII] emission and star formation in late-type galaxies

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

29

Stars: Formation, Galaxies: Ism, Galaxies: Spiral, Infrared: Galaxies

Scientific paper

We demonstrate the existence of a reasonably tight linear correlation between the ratio of the [CII (^2P_3/2-^2 P_1/2)] (lambda 158 mu m) fine-structure cooling line intensity to the [^12CO (J=1 -> 0)] (lambda 2.6 mm) line emission, I_CII/I_CO, and the H alpha (lambda 6563 A ) equivalent width (EW), over the range 2-71 A in H alpha EW, for a sample of 21 late-type galaxies. The latter is composed of an optically selected sample of 12 normal Virgo cluster spiral galaxies with [CII] detections obtained by us with LWS on board ISO, supplemented by nine galaxies with higher star formation rates (SFRs), for which [CII] data and, in particular, H alpha EW data are available in the literature. We infer I_CII/I_CO to be a reliable tracer of the current normalized, global SFR for non-starburst spiral galaxies. Moreover, we find that the ratio of the [CII] line to the total far-infrared (FIR) continuum intensity, I_CII/I_FIR, decreases from ~ 0.5 to ~ 0.1 per cent with decreasing SFR, which we propose is due to a `[CII]-quiet' component of I_FIR from dust heated by the general interstellar radiation field. The more `quiescent' galaxies in the sample have I_CII/I_CO different from those observed in `compact' Galactic interstellar regions. Therefore their [CII] emission is interpreted to be dominated by diffuse regions of the interstellar medium. For normal `star-forming' galaxies the diffuse component of the [CII] emission is estimated to account for at least 50 per cent of the total.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

[CII] emission and star formation in late-type galaxies 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 [CII] emission and star formation in late-type galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and [CII] emission and star formation in late-type galaxies will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-945807

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.