The Clustering of Faint Galaxies on Small Angular Scales

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We present a preliminary measurement of the angular clustering of faint (R ≤ 25) field galaxies in which we concentrate on the behavior of w(θ) on small angular scales (θ 10''). The galaxies are strongly clustered and w(θ) is well-characterized by a power law of the form Aw θ⁻δ. The best-fitting value of the power law index, δ, is, however, steeper than the fiducial value of δ= 0.8, indicating there are more pairs of galaxies separated by θ 10'' in our sample than would be otherwise expected. Using the best-fitting form of w(θ), we estimate that 10% of the galaxies are in physically close pairs (separations 21 h⁻¹ kpc). This is a factor of order 2 larger than local galaxy samples, but comparable to galaxy samples with <z> 0.4. The mean redshift of our galaxies is of order 0.95, and, therefore, our result suggests that there was little or no evolution in the merger rate of galaxies between z 1 and z 0.4.