Details

Autor(en) / Beteiligte

• Kartaltepe, J. S
• Sanders, D. B
• Scoville, N. Z
• Calzetti, D
• Capak, P
• Koekemoer, A
• Mobasher, B
• Murayama, T
• Salvato, M
• Sasaki, S. S
• Taniguchi, Y

Titel

Evolution of the Frequency of Luminous (≥LV) Close Galaxy Pairs at z < 1.2 in the COSMOS Field

Ist Teil von

• The Astrophysical journal. Supplement series, 2007-09, Vol.172 (1), p.320-328

Ort / Verlag

IOP Publishing

Erscheinungsjahr

2007

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• We measure the fraction of luminous galaxies in pairs at projected separations of 5-20 kpc out to z = 1.2 in the Cosmic Evolution Survey (COSMOS) field using ACS images and photometric redshifts derived from an extensive multiwavelength data set. Analysis of a complete sample of 106,188 galaxies more luminous than M sub(V) = -19.8 ( similar to L sub(V)*) in the redshift range 0.1 < z < 1.2 yields 1749 galaxy pairs. These data are supplemented by a local (z = 0-0.1) value for the galaxy pair fraction derived from the Sloan Digital Sky Survey. After statistically correcting the COSMOS pair sample for chance line-of-sight superpositions, the evolution in the pair fraction is fit by a power law proportional to (1 - z) [unk] super(-3.1 plus or minus 0.1). If this strongly evolving pair fraction continues out to higher redshift, similar to 50% of all luminous galaxies at z similar to 2 are in close pairs. This clearly signifies that galaxy mergers are a very significant and possibly dominant mechanism for galaxy evolution during the epoch of galaxy formation at z = 1-3.