Robert H. Lupton

Early-type galaxies in the SDSS. III. The Fundamental Plane

A magnitude-limited sample of nearly 9000 early-type galaxies in the redshift range 0.01 ≤ z ≤ 0.3 was selected from the Sloan Digital Sky Survey (SDSS) using morphological and spectral criteria. The fundamental plane relation in this sample is Ro ∝ σ1.49±0.05I in the r* band. It is approximately the same in the g*, i*, and z* bands. Relative to the population at the median redshift in the sample, galaxies at lower and higher redshifts have evolved only a little. If the fundamental plane is used to quantify this evolution, then the apparent magnitude limit can masquerade as evolution; once this selection effect has been accounted for, the evolution is consistent with that of a passively evolving population that formed the bulk of its stars about 9 Gyr ago. One of the principal advantages of the SDSS sample over previous samples is that the galaxies in it lie in environments ranging from isolation in the field to the dense cores of clusters. The fundamental plane shows that galaxies in dense regions are slightly different from galaxies in less dense regions.

THE 3D POWER SPECTRUM FROM ANGULAR CLUSTERING OF GALAXIES IN EARLY SDSS DATA 1

Early photometric data from the Sloan Digital Sky Survey (SDSS) contain angular positions for 1.5 million galaxies. In companion papers, the angular correlation function w(θ) and two-dimensional power spectrum Cl of these galaxies are presented. Here we invert Limbers equation to extract the three-dimensional power spectrum from the angular results. We accomplish this using an estimate of dn/dz, the redshift distribution of galaxies in four different magnitude slices in the SDSS photometric catalog. The resulting three-dimensional power spectrum estimates from w(θ) and Cl agree with each other and with previous estimates over a range in wavenumbers 0.03 < k/(h Mpc-1) < 1. The galaxies in the faintest magnitude bin (21 < r* < 22, which have median redshift zm = 0.43) are less clustered than the galaxies in the brightest magnitude bin (18 < r* < 19 with zm = 0.17), especially on scales where nonlinearities are important. The derived power spectrum agrees with that of Szalay et al., who go directly from the raw data to a parametric estimate of the power spectrum. The strongest constraints on the shape parameter Γ come from the faintest galaxies (in the magnitude bin 21 < r* < 22), from which we infer Γ = 0.14 (95% CL).Early photometric data from the Sloan Digital Sky Survey (SDSS) contain angular positions for 1.5 million galaxies. In companion papers, the angular correlation function w(�) and 2D power spectrum Cl of these galaxies are presented. Here we invert Limber’s equation to extract the 3D power spectrum from the angular results. We accomplish this using an estimate of dn/dz, the redshift distribution of galaxies in four different magnitude slices in the SDSS photometric catalog. The resulting 3D power spectrum estimates from w(�) and Cl agree with each other and with previous estimates over a range in wavenumbers 0.03 < k/h Mpc −1 < 1. The galaxies in the faintest magnitude bin (21 < r ∗ < 22, which have median redshift zm = 0.43) are less clustered than the galaxies in the brightest magnitude bin (18 < r ∗ < 19 with zm = 0.17), especially on scales where nonlinearities are important. The derived power spectrum agrees with that of Szalay et al. (2001) who go directly from the raw data to a parametric estimate of the power spectrum. The strongest constraints on the shape parameter come from the faintest galaxies (in the magnitude bin 21 < r ∗ < 22), from which we infer = 0 .14 +0.11 −0.06 (95% C.L.).

THE DISTRIBUTION OF QUASARS AND GALAXIES IN RADIO COLOR-COLOR AND MORPHOLOGY DIAGRAMS

We positionally match the 6 cm GB6, 20 cm FIRST and NVSS, and 92 cm WENSS radio catalogs and find 16,500 matches in ~3,000 deg2 of sky. Using this unified radio database, we construct radio color-magnitude-morphology diagrams and find that they display a clear structure, rather than a random scatter. We propose a simple, yet powerful, method for morphological classification of radio sources based on FIRST and NVSS measurements. For a subset of matched sources, we find optical identifications using the SDSS Data Release 1 catalogs, and separate them into quasars and galaxies. Compact radio sources with flat radio spectra are dominated by quasars, while compact sources with steep spectra, and resolved radio sources, contain substantial numbers of both quasars and galaxies.

Multiwavelength view of SDSS galaxies

We summarize the detection rates at wavelengths other than optical for �99,000 galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 1 main spectroscopic sample. The analysis is based on positional cross-correlation with source catalogs from ROSAT, 2MASS, IRAS, GB6, FIRST, NVSS and WENSS surveys. We find that the rest-frame UV-IR broad-band galaxy SEDs form a remarkably uniform, nearly one parameter, family. As an example, the SDSS u and r band data, supplemented with redshift, can be used to predict K band magnitudes measured by 2MASS with an rms scatter of only 0.2 mag; when measurement uncertainties are taken into account, the astrophysical scatter appears not larger than �0.1 mag. 1. The fractions of SDSS galaxies detected at other wavelengths We report initial results from a program aimed at the characterization of multiwave- length properties of galaxies detected by SDSS. The details about the positional cross-

Software Standards, Methods and Quality Control for the Sloan Digital Sky Survey

The Sloan Digital Sky Survey (SDSS) Collaboration involves upwards of 50 scientists, many of whom are involved in the development and use of the software needed to acquire, process and archive the image and spectroscopic data sets. Fermilab has major responsibilities in the development and maintenance of the project`s software and for its software engineering practices. The authors report on the standards and methodologies they have developed in support of these activities.