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arXiv · 1001.2772

The CFHTLS Deep Catalog of Interacting Galaxies I. Merger Rate Evolution to z=1.2

Carrie R. Bridge·Raymond G. Carlberg·Mark Sullivan
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Abstract

We present the rest-frame optical galaxy merger fraction between 0.2 4sigma level of confidence. A mild trend, where massive galaxies with M>10^10.7 M_sun are undergoing fewer mergers than less massive systems M~10^10 M_sun), consistent with the expectations of galaxy assembly downsizing is observed. Our results also show that interacting galaxies have on average SFRs double that found in non-interacting field galaxies. We conclude that (1) the optical galaxy merger fraction does evolve with redshift, (2) the merger fraction depends mildly on stellar mass, with lower mass galaxies having higher merger fractions at z<1, and (3) star formation is triggered at all phases of a merger, with larger enhancements at later stages, consistent with N-body simulations.

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Carrie R. Bridge, Raymond G. Carlberg, Mark Sullivan. 2010-01-15. The CFHTLS Deep Catalog of Interacting Galaxies I. Merger Rate Evolution to z=1.2. https://doi.org/10.1088/0004-637x%2F709%2F2%2F1067

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