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The K-Band Galaxy Luminosity Function

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

We measured the K-band luminosity function using a complete sample of 4192 morphologically-typed 2MASS galaxies with 7 < K < 11.25 mag spread over 2.12 str. Early-type (T < -0.5) and late-type (T > -0.5) galaxies have similarly shaped luminosity functions, alpha_e=-0.92+/-0.10 and alpha_l=-0.87+/-0.09. The early-type galaxies are brighter, M_*e=-23.53+/-0.06 mag compared to M_*l=-22.98\pm0.06 mag, but less numerous, n_*e=(0.0045+/-0.0006)h^3/Mpc^3 compared to n_*l=(0.0101+/-0.0013)h^3/Mpc^3 for H_0=100h km/s Mpc, such that the late-type galaxies slightly dominate the K-band luminosity density, j_late/j_early=1.17+/-0.12. Our morphological classifications are internally consistent, 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.

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C. S. Kochanek, M. A. Pahre, E. E. Falco, J. P. Huchra, J. Mader, T. H Jarrett, T. Chester, R. Cutri, S. E. Schneider. 2000-11-24. The K-Band Galaxy Luminosity Function. https://doi.org/10.1086/322488

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