The K-Band Galaxy Luminosity Function

October 2001 • 2001ApJ...560..566K

Authors • Kochanek, C. S. • Pahre, M. A. • Falco, E. E. • Huchra, J. P. • Mader, J. • Jarrett, T. H. • Chester, T. • Cutri, R. • Schneider, S. E.

Abstract • We measured the K-band luminosity function using a complete sample of 4192 morphologically typed 2MASS galaxies with μ_Ks=20 mag arcsec^-2 isophotal magnitudes 7<K₂₀<11.25 mag spread over 2.12 sr. Early-type (T<=-0.5) and late-type (T>-0.5) galaxies have similarly shaped luminosity functions, α_e=-0.92+/-0.10 and α_l=-0.87+/-0.09. The early-type galaxies are brighter, M_K*e=-23.53+/-0.06 mag compared to M_K*l=-22.98+/-0.06 mag, but less numerous, n_*e=(0.45+/-0.06)×10^-2 h³ Mpc^-3 compared to n_*l=(1.01+/-0.13)×10^-2 h³ Mpc^-3 for H₀=100 h km s^-1 Mpc^-1, such that the late-type galaxies slightly dominate the K-band luminosity density, j_late/j_early=1.17+/-0.12. Including a factor of 1.20+/-0.04 correction for the conversion of the isophotal survey magnitudes to total magnitudes, the local K-band luminosity density is j=(7.14+/-0.75)×10⁸ h L_solar Mpc^-3, which implies a stellar mass density relative to critical of Ω_*h=(1.9+/-0.2)×10^-3 for a Kennicutt initial mass function (IMF) and Ω_*h=(3.4+/-0.4)×10^-3 for a Salpeter IMF. Our morphological classifications are internally consistent, are consistent with previous classifications, and lead to luminosity functions unaffected by the estimated uncertainties in the classifications. These luminosity functions accurately predict the K-band number counts and redshift distributions for K<~18 mag, beyond which the results depend on galaxy evolution and merger histories. This publication makes use of data products from the Two Micron All Sky Survey (2MASS), which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

Links

• PREPRINT http://arxiv.org/abs/astro-ph/0011456
• NED https://ned.ipac.caltech.edu/uri/NED::InRefcode/2001ApJ...560..566K
• ELECTR https://doi.org/10.1086%2F322488
• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2001ApJ...560..566K
• PDF https://stacks.iop.org/0004-637X/560/566/pdf
• DATA http://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/560/566
• SPIRES http://inspirehep.net/search?p=find+eprint+astro-ph/0011456