The galaxy luminosity function in the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap

Abstract

We present optical luminosity functions (LFs) of galaxies in the ${}^{0.1}g$, ${}^{0.1}r$, and ${}^{0.1}i$ bands, calculated using data in $\sim 40$ $de{g}^2$ sky area of LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in Southern Galactic Cap. Redshifts for galaxies brighter $r=18.1$ were obtained mainly with LAMOST. In each band, LFs derived using both parametric and non-parametric maximum likelihood methods agree well with each other. In the ${}^{0.1}r$ band, our fitting parameters of the Schechter function are $\ddot{I}{•}_{\ast }=(1.65\pm 0.36)\times 10^{-2}{h}^{3}Mp{c}^{-3}$, $M_{\ast }=-20.69\pm 0.06$ mag, and $\hat{I}\pm =-1.12\pm 0.08$, in agreements with previous studies. Separate LFs are also derived for emission line galaxies and absorption line galaxies, respectively. The LFs of absorption line galaxies show a dip at ${}^{0.1}r\sim 18.5$ and can be well fitted by a double-Gaussian function, suggesting a bi-modality in passive galaxies.

14 pages, 9 figures and 4 tables, accepted for publication in RAA