The Power Spectrum of Galaxy Clustering in the Las Campanas Redshift Survey

The Las Campanas Redshift Survey (LCRS) contains 23697 galaxies, with an average redshift $z = 0.1$, distributed over six $1.5arcdeg$ by $80arcdeg$ slices in the North and South galactic caps. We have computed the power spectrum $P(k)$ for LCRS galaxies over wavelengths $lambda = 2pi / k = 5 - 400 h^{-1}$~Mpc. The LCRS $P(k)$ may be approximated as $propto k^{-1.8 pm 0.1}$ for small scales $lambda = 5 - 30 h^{-1}$~Mpc, changing to $propto k^{1 pm 1}$ for large scales $lambda approx 200 - 400 h^{-1}$~Mpc. The overall amplitude corresponds to $sigma_8 = 1.0 pm 0.1$ in redshift space. Comparisons to the power spectra of other redshift surveys will be presented; the LCRS results agree best with those from the combined Center for Astrophysics and Southern Sky redshift surveys. We find evidence for type- dependent clustering differences in the LCRS, such that galaxies brighter than about $M^* - 1$ appear about 50% more strongly clustered than those fainter, and that a sample of emission galaxies shows 30% weaker clustering than the full LCRS sample. On large scales $lambda gtrsim 40 h^{-1}$~Mpc, we have also fit the LCRS results to various linear CDM models, and find that a number of them could meet the constraints set by the LCRS power spectrum, the Hubble constant range $0.5 lesssim h lesssim 0.8$, the abundance of galaxy clusters, and the reasonable assumption that LCRS galaxies are roughly unbiased tracers of the mass, relative to the normalization provided by the 4-year COBE DMR data. The possibilites include open CDM or flat non-zero cosmological-constant CDM models with $Omega_0 approx 0.4-0.6$ and shape parameter $Gamma approx 0.2-0.3$, as well as flat $Omega_0 = 1$ models with massive neutrino density $Omega_ u approx 0.2-0.3$ or a spectral tilt $n approx 0.7-0.8$. (abridged)Comment: 48 pages, including 15 of 16 postscript figures, uses AASTEX v4.0 style files, to appear in ApJ. The full paper is available at http://manaslu.astro.utoronto.ca/~lin/lcrs.html (North America) and http://www.aip.de:8080/~tucker/lcrs-mirror.html (Europe