THE DURHAM UKST GALAXY REDSHIFT SURVEY - III - LARGE-SCALE STRUCTURE VIA THE 2-POINT CORRELATION-FUNCTION/

We have investigated the statistical clustering properties of galaxies by calculating the two-point galaxy correlation function from the opt ically selected Durham/UKST Galaxy Redshift Survey. This survey is mag nitude-limited to b(J) similar to 17, contains similar to 2500 galaxie s sampled at a rate of one-in-three and surveys a similar to 4 x 10(6) (h(-1) Mpc)(3) volume of space. We have empirically determined the op timal method of estimating the two-point correlation function from jus t such a magnitude-limited survey. Applying our methods to this survey , we find that our redshift-space results agree well with those from p revious optical surveys. In particular, we confirm the previously clai med detections of large-scale power out to similar to 40 h(-1) Mpc sca les. We compare with two common models of cosmological structure forma tion and find that our two-point correlation function has power signif icantly in excess of the standard cold dark matter model in the 10-30 h(-1) Mpc region. We therefore support the observational results of th e APM galaxy survey. Given that only the redshift-space clustering can be measured directly, we use standard modelling methods and indirectl y estimate the real-space two-point correlation function from the proj ected two-point correlation function. We then invert this projected co rrelation function to obtain an estimate of the spatial two-point corr elation function in real space. This correlation function in real spac e has a lower amplitude than that in redshift space, but a steeper slo pe.