Details

Autor(en) / Beteiligte

• Trujillo, Ignacio
• Conselice, C. J.
• Bundy, Kevin
• Cooper, M. C.
• Eisenhardt, P.
• Ellis, Richard S.

Titel

Strong size evolution of the most massive galaxies since z ∼ 2

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2007-11, Vol.382 (1), p.109-120

Ort / Verlag

Oxford, UK: Blackwell Publishing Ltd

Erscheinungsjahr

2007

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Using the combined capabilities of the large near-infrared Palomar/DEEP-2 survey, and the superb resolution of the Advanced Camera for Surveys HST camera, we explore the size evolution of 831 very massive galaxies (M⋆≥ 1011h−270 M⊙) since z∼ 2. We split our sample according to their light concentration using the Sérsic index n. At a given stellar mass, both low (n < 2.5) and high (n > 2.5) concentrated objects were much smaller in the past than their local massive counterparts. This evolution is particularly strong for the highly concentrated (spheroid like) objects. At z∼ 1.5, massive spheroid-like objects were a factor of 4 (±0.4) smaller (i.e. almost two orders of magnitudes denser) than those we see today. These small sized, high-mass galaxies do not exist in the nearby Universe, suggesting that this population merged with other galaxies over several billion years to form the largest galaxies we see today.