Journal Article

The luminosity function, halo masses and stellar masses of luminous Lyman-break galaxies at redshifts 5 < z < 6

R. J. McLure, M. Cirasuolo, J. S. Dunlop, S. Foucaud and O. Almaini

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 395, issue 4, pages 2196-2209
Published in print June 2009 | ISSN: 0035-8711
Published online May 2009 | e-ISSN: 1365-2966 | DOI:
The luminosity function, halo masses and stellar masses of luminous Lyman-break galaxies at redshifts 5 < z < 6

Show Summary Details


We present the results of a study of a large sample of luminous (zAB < 26) Lyman-break galaxies (LBGs) in the redshift interval 4.7 < z < 6.3, selected from a contiguous 0.63 deg2 area covered by the UKIRT Infrared Deep Sky Survey Ultra Deep Survey and the Subaru XMM–Newton Survey. Utilizing the large area coverage and the excellent available optical+near-infrared data, we use a photometric redshift analysis to derive a new, robust, measurement of the bright end (LL) of the ultraviolet-selected luminosity function at high redshift. When combined with literature studies of the fainter LBG population, our new sample provides improved constraints on the luminosity function of redshift 5 < z < 6 LBGs over the luminosity range 0.1LL≲ 10L. A maximum likelihood analysis returns best-fitting Schechter function parameters of M1500=−20.73 ± 0.11, φ= 0.0009 ± 0.0002 Mpc−3 and α=−1.66 ± 0.06 for the luminosity function at z= 5, and M1500=−20.04 ± 0.12, φ= 0.0018 ± 0.0005 Mpc−3 and α=−1.71 ± 0.11 at z= 6. In addition, an analysis of the angular clustering properties of our LBG sample demonstrates that luminous 5 < z < 6 LBGs are strongly clustered (r0= 8.1+2.1−1.5h−170 Mpc), and consistent with the occupation of dark matter haloes with masses of ≃1011.5−12 M. Moreover, by stacking the available multiwavelength imaging data for the high-redshift LBGs, it is possible to place useful constraints on their typical stellar mass. The results of this analysis suggest that luminous LBGs at 5 < z < 6 have an average stellar mass of log10(M/M) = 10.0+0.2−0.4, consistent with the results of the clustering analysis assuming plausible values for the ratio of stellar to dark matter. Finally, by combining our luminosity function results with those of the stacking analysis we derive estimates of ≃1 × 107 and ≃4 × 106 M Mpc−3 for the stellar mass density at z≃ 5 and 6, respectively.

Keywords: galaxies: evolution; galaxies: formation; galaxies: high-redshift

Journal Article.  11122 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.