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arXiv · 1505.01003

Galaxy and Mass Assembly (GAMA): maximum likelihood determination of the luminosity function and its evolution

J. Loveday·P. Norberg·I. K. Baldry·J. Bland-Hawthorn·S. Brough·M. J. I. Brown·S. P. Driver·L. S. Kelvin·S. Phillipps
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Abstract

We describe modifications to the joint stepwise maximum likelihood method of Cole (2011) in order to simultaneously fit the GAMA-II galaxy luminosity function (LF), corrected for radial density variations, and its evolution with redshift. The whole sample is reasonably well-fit with luminosity (Qe) and density (Pe) evolution parameters Qe, Pe = 1.0, 1.0 but with significant degeneracies characterized by Qe = 1.4 - 0.4Pe. Blue galaxies exhibit larger luminosity density evolution than red galaxies, as expected. We present the evolution-corrected r-band LF for the whole sample and for blue and red sub-samples, using both Petrosian and Sersic magnitudes. Petrosian magnitudes miss a substantial fraction of the flux of de Vaucouleurs profile galaxies: the Sersic LF is substantially higher than the Petrosian LF at the bright end.

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J. Loveday, P. Norberg, I. K. Baldry, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, S. P. Driver, L. S. Kelvin, S. Phillipps. 2015-05-05. Galaxy and Mass Assembly (GAMA): maximum likelihood determination of the luminosity function and its evolution. https://arxiv.org/abs/1505.01003

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