English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present new estimates of the spatial two-point correlation function ofrich clusters of galaxies selected from the APM Galaxy Survey. We have measuredredshifts for a sample of $364$ clusters out to a depth of $\sim 450\hmpc$. Theclusters have a mean space density of $\bar{n} = 3.4\times 10^{-5}\hmpccc$. Thetwo-point correlation function, $\xi_{cc}$, for this sample is equal to unityat a pair-separation of $r_0 = 14.3\pm1.75\hmpc$ (2$\sigma$ errors), consistentwith our earlier results from a smaller sample. The new observations provide anaccurate determination of the shape of $\xi_{cc}$ to pair-separations of about$50\hmpc$. Our results show that $\xi_{cc}$ has a higher amplitude thanexpected according to the standard $\Omega=1$ cold dark matter (CDM) model onspatial scales $2\simlt s \simlt 50\hmpc$, but are in good agreement withscale-invariant fluctuations in either a low density CDM model or a criticaldensity universe made up of a mixture of hot and cold dark matter. Our resultsprovide strong constraints on so called `co-operative' models of galaxyformation in which the galaxy formation process introduces large-scalestructure in the galaxy distribution.Comment: 5 pages, uuencoded compressed postscript (4 figures), submitted to  MNRA

The two-point correlation function of rich clusters of galaxies: results from an extended APM cluster redshift survey