The 2dF Galaxy Redshift Survey: spectral types and luminosity functions


Folkes, Simon; Ronen, Shai; Price, Ian; Lahav, Ofer; Colless, Matthew; Maddox, Stephen J.; Deeley, Kathryn; Glazebrook, Karl; Bland-Hawthorn, Joss; Cannon, Russell D.; Cole, Shaun; Collins, Chris A.; Couch, Warrick J.; Driver, Simon P.; Dalton, Gavin B.; Efstathiou, George P.; Ellis, Richard S.; Frenk, Carlos S.; Kaiser, Nicholas; Lewis, Ian; Lumsden, Stuart L.; Peacock, John A.; Peterson, Bruce A.; Sutherland, William J.; Taylor, Keith

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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 comparison with 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 Ω=1, H0=100 km s−1 Mpc−1), α=−1.3, φ*=0.017. For class 1 ('early-type') we find M*=−19.6, α=−0.7, while for class 5 ('late-type') we find M*=−19.0, α=−1.7. The derived 2dF luminosity functions agree well with other recent luminosity function estimates.

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Journal article


Monthly Notices of the Royal Astronomical Society, Vol. 308, no. 2 (Sep 1999), pp. 459-472






Copyright © 1999 Royal Astronomical Society. The accepted manuscript is reproduced in accordance with the copyright policy of the publisher. The definitive publication is available at