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arXiv · 0709.1737

The Fundamental Plane of Bulges at Intermediate Redshift

Lauren A. MacArthur·Richard S. Ellis·Tommaso Treu
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Abstract

We report on a new study aimed at understanding the diversity and evolutionary properties of distant galactic bulges in the context of well-established trends for pure spheroidal galaxies. Bulges have been isolated for a sample of 137 spiral galaxies in the GOODS fields within the redshift range 0.1 < z < 1.2. Using proven photometric techniques we determine for each galaxy the characteristic parameters (size, surface brightness, profile shape) in the 4 GOODS-ACS imaging bands of both the disk and bulge components. Using the DEIMOS spectrograph on Keck, precision stellar velocity dispersions were secured for a sizeable fraction of the bulges. This has enabled us to compare the Fundamental Plane of our distant bulges with that of field spheroidal galaxies in a similar redshift range. Bulges in spiral galaxies with a bulge-to-total luminosity ratio (B/T) > 0.2 show very similar patterns of evolution to those seen for low luminosity spheroidals. To first order, their recent mass assembly histories are equivalent.

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Lauren A. MacArthur, Richard S. Ellis, Tommaso Treu. 2007-09-12. The Fundamental Plane of Bulges at Intermediate Redshift. https://doi.org/10.1017/s1743921308018322

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