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arXiv · 0909.1940

Introducing the Photometric Maximum Likelihood Method: Galaxy Luminosity Functions at z<1.2 in MUSYC-ECDFS

Daniel Christlein·Eric Gawiser·Danilo Marchesini·Nelson Padilla
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Abstract

We present a new maximum likelihood method for the calculation of galaxy luminosity functions from multi-band photometric surveys without spectroscopic data. The method evaluates the likelihood of a trial luminosity function by directly comparing the predicted distribution of fluxes in a multi-dimensional photometric space to the observations, and thus does not require the intermediate step of calculating photometric redshifts. We apply this algorithm to ~27,000 galaxies with m_R<=25 in the MUSYC-ECDFS field, with a focus on recovering the luminosity function of field galaxies at z<1.2. Our deepest LFs reach M_r=-14 and show that the field galaxy LF deviates from a Schechter function, exhibiting a steep upturn at intermediate magnitudes that is due to galaxies of late spectral types.

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Daniel Christlein, Eric Gawiser, Danilo Marchesini, Nelson Padilla. 2009-09-10. Introducing the Photometric Maximum Likelihood Method: Galaxy Luminosity Functions at z<1.2 in MUSYC-ECDFS. https://doi.org/10.1111/j.1365-2966.2009.15474.x

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