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The Angular Correlation Function of K=19.5 Galaxies and the Detection of a Cluster at z=0.775

Nathan Roche·Steve Eales·Hans Hippelein·Chris Willott
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Abstract

On five K-band Omega camera images, covering a total of 162.2 sq. arcmin to K=19.5, we investigate (i) the clustering environment of 5 radio galaxies at 0.7 1.5) redshifts. We also find a significant excess of 1.5--5.0 arcsec separation pairs of galaxies compared to the expectation from the inward extrapolation of omega(theta). To K=19.5, we estimate that 11.0\pm 3.4 per cent of galaxies are in close pairs in excess of omega(theta). This can be explained if the local rate of galaxy mergers and interactions increases with redshift as $\sim (1+z)^m$ with $m=1.33_{-0.51}^{+0.36}$.

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Nathan Roche, Steve Eales, Hans Hippelein, Chris Willott. 1998-12-03. The Angular Correlation Function of K=19.5 Galaxies and the Detection of a Cluster at z=0.775. https://doi.org/10.1046/j.1365-8711.1999.02536.x

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