AAS Meeting #193 - Austin, Texas, January 1999
Session 2. Galaxy Evolution and Surveys I - Low Redshift
Display, Wednesday, January 6, 1999, 9:20am-6:30pm, Exhibit Hall 1

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[2.04] Precision measurements from the Las Campanas Suryey -- two-point, three point correlation functions and the pairwise velocity dispersion of galaxies

G. B\"orner (MPA), I.P. Jing (RESCEU), H.J. Mo (MPA)

Three of the most fundamental quantities in the large-scale structure studies, i.e. the real-space two--point correlation function (2PCF), the three--point correlation function (3PCF), and the pairwise velocity dispersion of galaxies (PVD) can all be measured reliably from the Las Campanas Redshift Survey (LCRS). An important aspect of our studies is the use of a number of mock catalogs derived from large simulations to guide the statistical analysis, such that both the error measurement, as well as the quantification of any systematic effect (either in the observations or in the statistical methods) can be done reliably.

The results for the real--space 2CPF can be well fitted by a power law: \[ \xi(r) = (r0/r)\gamma\] with \[ r0=(5.06±.12)h-1Mpc \] and \[ \gamma = 1.862±.034 \] The PVD at a separation of 1 h{-1} Mpc is \[ 570±0 km s{-1} \].

The 3PCF has small but significant deviations from the well--known hierarchical form. The projected Q--value can be fitted approximately by Q(rp, u, v) = 0.7 rp-0.3 (rp in units of h-1 Mpc).

A detailed comparison between these observational results and the predictions of CDM cosmogonies is carried out. A flat model with \Omega = 0.2 meets the 2PCF and PVD constraints, but gives higher values for the 3PCF than observed.

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