2003/11/05 by H. Flores, F. Hammer, D. Elbaz +5 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1051/0004-6361:20034491
published as Astron.Astrophys. 415 (2004) 885-888 · (1) GEPI, Obs. Meudon, France ;(2) CEA-Saclay, France ;(3) ESO, Gemany ;(4) IAC, Spain. To appear in A&A
arxiv created 2003/11/05 · openalex publication_date 2004/02/13 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present a study of the star formation rate (SFR) for a sample of 16 distant galaxies detected by ISOCAM at 15 μm in the CFRS0300+00 and CFRS1400+52 fields. Their high quality and intermediate resolution VLT/FORS spectra have allowed a proper correction of the Balmer emission lines from the underlying absorption. Extinction estimates using the Hβ/Hγ and the Hα/Hβ Balmer decrement are in excellent agreement, providing a robust measurement of the instantaneous SFR based on the extinction-corrected Hα luminosity. Star formation has also been estimated exploiting the correlations between IR luminosity and those at MIR and radio wavelengths. Our study shows that the relationship between the two SFR estimates follow two distinct regimes: (1) for galaxies with SFRIR below ~100 /yr, the SFR deduced from Hα measurements is a good approximation of the global SFR and (2) for galaxies near ULIRG regime. The corrected Hα SFR understimated the SFR by a factor of 1.5 to 2. Our analyses suggest that heavily extincted regions completely hidden in optical bands (such as those found in Arp 220) contribute less than 20% of the global budget of star formation up to .