The 2dF Galaxy Redshift Survey: Spectral Types and Luminosity Functions

S. R. Folkes; S. Ronen; I. Price; O. Lahav; M. Colless; S. J. Maddox; K. E. Deeley; K. Glazebrook; J. Bland-Hawthorn; R. D. Cannon; S. Cole; C. A. Collins; W. J. Couch; S. P. Driver; G. Dalton; G. Efstathiou; R. S. Ellis; C. S. Frenk; N. Kaiser; I. J. Lewis; S. L. Lumsden; J. A. Peacock; B. A. Peterson; W. Sutherland; K. Taylor

doi:10.1046/j.1365-8711.1999.02721.x

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arXiv · astro-ph/9903456

The 2dF Galaxy Redshift Survey: Spectral Types and Luminosity Functions

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Abstract

We describe the 2dF Galaxy Redshift Survey (2dFGRS), and the current status of the observations. In this exploratory paper, we apply a Principal Component Analysis to a preliminary sample of 5869 galaxy spectra and use the two most significant components to split the sample into five spectral classes. These classes are defined by considering visual classifications of a subset of the 2dF spectra, and also by comparing to high quality spectra of local galaxies. We calculate a luminosity function for each of the different classes and find that later-type galaxies have a fainter characteristic magnitude, and a steeper faint-end slope. For the whole sample we find M*=-19.7 (for Omega=1, H_0=100 km/sec/Mpc), alpha=-1.3, phi*=0.017. For class 1 (`early-type') we find M*=-19.6, alpha=-0.7, while for class 5 (`late-type') we find M*=-19.0, alpha=-1.7. The derived 2dF luminosity functions agree well with other recent luminosity function estimates.

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S. R. Folkes, S. Ronen, I. Price, O. Lahav, M. Colless, S. J. Maddox, K. E. Deeley, K. Glazebrook, J. Bland-Hawthorn, R. D. Cannon, S. Cole, C. A. Collins, W. J. Couch, S. P. Driver, G. Dalton, G. Efstathiou, R. S. Ellis, C. S. Frenk, N. Kaiser, I. J. Lewis, S. L. Lumsden, J. A. Peacock, B. A. Peterson, W. Sutherland, K. Taylor. 1999-03-30. The 2dF Galaxy Redshift Survey: Spectral Types and Luminosity Functions. https://doi.org/10.1046/j.1365-8711.1999.02721.x

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