Galaxy Evolution and Star Formation Efficiency in the Last Half of the Universe

F. Combes (1, 2, 3) , S. Garcia-Burillo , J. Braine (4, 5, 6) , E. Schinnerer , F. Walter (7) , L. Colina , M. Gerin (1, 8)

1 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique
2 DEMIRM - Departement de Radioastronomie Millimétrique
3 IBENS - Institut de biologie de l'Ecole Normale Supérieure
4 L3AB - Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux
5 OASU - Observatoire aquitain des sciences de l'univers
6 LAB - Laboratoire d'Astrophysique de Bordeaux [Pessac]
7 MPIA - Max-Planck-Institut für Astronomie
8 LRA - Laboratoire de Radioastronomie

We present the results of a CO(1-0) emission survey with the IRAM 30m of 30 galaxies at moderate redshift (z ~ 0.2-0.6) to explore galaxy evolution and in particular the star formation efficiency, in the redshift range filling the gap between local and very high-z objects. Our detection rate is about 50%. One of the bright objects was mapped at high resolution with the IRAM interferometer, and about 50% of the total emission found in the 27 arcsec (97 kpc) single dish beam is recovered by the interferometer, suggesting the presence of extended emission. The FIR-to-CO luminosity ratio is enhanced, following the increasing trend observed between local and high-z ultra-luminous starbursts.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Astrophysique [astro-ph]

F. Combes, S. Garcia-Burillo, J. Braine, E. Schinnerer, F. Walter, et al.. Galaxy Evolution and Star Formation Efficiency in the Last Half of the Universe. SF2A-2007, Jul 2007, Grenoble, France. pp.312. ⟨hal-00265497⟩