[CII] 158 μm Emission as a Star Formation Tracer
Abstract
The [CII] 158 μm transition is a major coolant for the interstellar gas and has great potential as a star formation rate tracer. Thanks to ALMA, the [CII] 158 μm line will be detected in normal, star forming galaxies at redshift z>1. Using a sample of 49 nearby galaxies observed by Herschel as part of the KINGFISH project, we analyze how reliable is to measure the star formation rate using the [CII] 158 μm transition. We present resolved correlations of the [CII] 158 μm transition with recently published prescriptions for star formation rates based on 24 μm, Hα and FUV emission. We find a strong, nearly linear correlation between the [CII] 158 μm luminosity surface density and the star formation rate surface density. We conclude that the [CII] emission can be used for measurements of SFRs in normal, star forming galaxies in the absence of strong AGNs. The uncertainty associated to the [CII]-SFR calibration is ~0.2 dex. We test the correlation using a simple model based on the Starburst99 code to connect the star formation rate of a stellar population to the [CII] 158 μm emission. We find that most of the regions can be described by a star formation episode that is 20-100 Myr old and photoelectric heating efficiencies in the 1-3%. range The variations in the latter appear to drive much of the scatter in the [CII]-SFR correlation.
- Publication:
-
American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22311702H