The Local Galaxy 8 micron Luminosity Function
Abstract
A SST survey in the NOAO Deep-Wide Field in Bo\"otes provides a complete, 8-micron-selected sample of galaxies to a limiting (Vega) magnitude of 13.5. In the 6.88 deg field sampled, 79% of the 4867 galaxies have spectroscopic redshifts, allowing an accurate determination of the local (z<0.3) galaxy luminosity function. Stellar and dust emission can be separated on the basis of observed galaxy colors. Dust emission (mostly PAH) accounts for 80% of the 8 micron luminosity, stellar photospheres account for 19%, and AGN emission accounts for roughly 1 %. A sub-sample of the 8 micron-selected galaxies have blue, early-type colors, but even most of these have significant PAH emission. The luminosity functions for the total 8 micron luminosity and for the dust emission alone are both well fit by Schechter functions. For the 8 micron luminosity function, the characteristic luminosity is \nu L_{\nu}^*(8.0 \micron) = 1.8 \times 10^{10} \Lsun\null. The average 8 \micron luminosity density at z<0.3 is 3.1 x 10^7 \Lsun Mpc^{-3}, and the average luminosity density from dust alone is 2.5 x 10^7 \Lsun Mpc^{-3}. This luminos ity arises predominantly from galaxies with 8 \micron luminosities () between and \Lsun, i.e., normal galaxies, not LIRGs or ULIRGs.
Cite
@article{arxiv.0704.3609,
title = {The Local Galaxy 8 micron Luminosity Function},
author = {J. -S. Huang and M. L. N. Ashby and P. Barmby and M. Brodwin and M. J. I. Brown and N. Caldwell and R. J. Cool and P. Eisenhardt and D. Eisenstein and G. G. Fazio and E. Le Floc'h and P. Green and C. S. Kochanek and N. Y. Lu and M. A. Pahre and D. Rigopoulou and J. L. Rosenberg and H. A. Smith and Z. Wang and C. N. A. Willmer and S. P. Willner},
journal= {arXiv preprint arXiv:0704.3609},
year = {2009}
}