Spectroscopic Target Selection for the Sloan Digital Sky Survey: The Luminous Red Galaxy Sample

We describe the target selection and resulting properties of a spectroscopicsample of luminous, red galaxies (LRG) from the imaging data of the SloanDigital Sky Survey (SDSS). These galaxies are selected on the basis of colorand magnitude to yield a sample of luminous, intrinsically red galaxies thatextends fainter and further than the main flux-limited portion of the SDSSgalaxy spectroscopic sample. The sample is designed to impose apassively-evolving luminosity and rest-frame color cut to a redshift of 0.38.Additional, yet more luminous, red galaxies are included to a redshift of 0.5.Approximately 12 of these galaxies per square degree are targeted forspectroscopy, so the sample will number over 100,000 with the full survey. SDSScommissioning data indicate that the algorithm efficiently selects luminous(M_g=-21.4), red galaxies, that the spectroscopic success rate is very high,and that the resulting set of galaxies is approximately volume-limited out toz=0.38. When the SDSS is complete, the LRG spectroscopic sample will fill over1h^-3 Gpc^3 with an approximately homogeneous population of galaxies and willtherefore be well suited to studies of large-scale structure and clusters outto z=0.5.Comment: 30 pages, LaTeX. Accepted to the Astronomical Journa