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arXiv · 0804.2336

Color Profiles of Disk Galaxies since z~1: Probing Outer Disk Formation Scenarios

Ruyman Azzollini·Ignacio Trujillo·John E. Beckman
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Abstract

We present deep color profiles for a sample of 415 disk galaxies within the redshift range 0.1<z<=1.1, and contained in HST-ACS imaging of the GOODS-South field (Giavalisco et al. 2004). For each galaxy, passband combinations are chosen to obtain, at each redshift, the best possible aproximation to the rest-frame u-g color. We find that objects which show a truncation in their stellar disk (Type II objects) usually show a minimum in their color profile at the break, or very near to it, with a maximum to minimum amplitude in color of <~0.2 mag/arcsec^2, a feature which is persistent through the explored range of redshifts (i.e. in the last ~8 Gyr). This color structure is in qualitative agreement with recent model expectations (Roskar et al. 2008) where the break of the surface brightness profiles is the result of the interplay between a radial star formation cut-off and a redistribution of stellar mass by secular processes.

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Ruyman Azzollini, Ignacio Trujillo, John E. Beckman. 2008-04-15. Color Profiles of Disk Galaxies since z~1: Probing Outer Disk Formation Scenarios. https://doi.org/10.1086/589283

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