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Session 87 - Large Scale Structure.
Display session, Friday, January 09
Exhibit Hall,

[87.12] A Nearly-Constant Clustering Amplitude for Faint Galaxies

T. G. Brainerd (Boston U.), I. Smail (U. Durham)

The angular clustering of faint field galaxies is investigated using deep imaging (I\sim 25) obtained with the 10-m Keck--I telescope. The autocorrelation function is consistent with ømega(\theta) \propto \theta^-0.8, and we find no compelling evidence for a flattening of the power law index at the faintest magnitude limits. Results from a number of independent observational studies are combined in order to investigate the variation of the correlation amplitude with median I-magnitude. At I_med\sim 23 the results obtained by different studies are all in rough agreement and indicate that for I_med > 22 the correlation amplitude declines far less steeply than would be expected from an extrapolation of the trend in the brighter samples. In particular, at I_med \sim 24 our data indicate ømega(\theta) to be a factor \sim 7 higher than the extrapolation. A flattening of the correlation amplitude at faint magnitude limits is a general feature of models in which the redshift distribution of the faint field population contains a substantial fraction of objects at z > 1 and in order to reproduce the apparent abrupt flattening of the amplitude of ømega(\theta) observed at the faintest limits, of order 50% of the galaxies in a sample with I_med \sim 24 must be at z > 1.

Program listing for Friday