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arXiv · 1202.5403

Fast evolving size of early-type galaxies at z>2 and the role of dissipationless (dry) merging

A. Cimatti·C. Nipoti·P. Cassata
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Abstract

We present the analysis of a large sample of early-type galaxies (ETGs) at 0 2 are removed from the sample, suggesting an accelerated increase of the typical sizes at z>2, especially for the ETGs with the largest masses. A pure dry merging LambdaCDM model is marginally consistent with the average size evolution at 0 2 progenitor ETGs. This opens the crucial question on what physical mechanism can explain the accelerated evolution at z>2, or whether an unclear observational bias is partly responsible for that.

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A. Cimatti, C. Nipoti, P. Cassata. 2012-02-24. Fast evolving size of early-type galaxies at z>2 and the role of dissipationless (dry) merging. https://doi.org/10.1111/j.1745-3933.2012.01237.x

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