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arXiv · 1303.3005

Photometric Redshifts and Systematic Variations in the SEDs of Luminous Red Galaxies from the SDSS DR7

Natascha Greisel·Stella Seitz·Niv Drory·Ralf Bender·Roberto Saglia·Jan Snigula
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Abstract

We describe the construction of a template set of spectral energy distributions (SEDs) for the estimation of photometric redshifts of luminous red galaxies (LRGs) with a Bayesian template fitting method. By examining the color properties of several publicly available SED sets within a redshift range of 0 0.15) of 0.12%. We show that templates that optimally describe the brightest galaxies (-24.5<M_R<-22.7) indeed vary from z=0.1 to z=0.5, consistent with aging of the stellar population. Furthermore, we find that templates that optimally describe galaxies at z<0.1 strongly differ as a function of the absolute magnitude of the galaxies, indicating an increase in star formation activity for less luminous galaxies. Our findings based on the photometry of the SDSS LRGs and our SED template fitting are supported by comparison to the average SDSS LRG spectra in different luminosity and redshift bins.

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Natascha Greisel, Stella Seitz, Niv Drory, Ralf Bender, Roberto Saglia, Jan Snigula. 2013-03-12. Photometric Redshifts and Systematic Variations in the SEDs of Luminous Red Galaxies from the SDSS DR7. https://doi.org/10.1088/0004-637x/768/2/117

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