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A Robust Estimator of the Small-Scale Galaxy Correlation Function

Nikhil Padmanabhan·Martin White·Daniel J. Eisenstein
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Abstract

We present a new estimator, omega, of the small scale galaxy correlation function that is robust against the effects of redshift space distortions and large scale structures. The estimator is a weighted integral of the redshift space or angular correlation function and is a convolution of the real space correlation function with a localized filter. This allows a direct comparison with theory, without modeling redshift space distortions and the large scale correlation function. This has a number of advantages over the more traditional w_p estimator, including (i) an insensitivity to large scale structures and the details of the truncation of the line of sight integral, (ii) a compact kernel in xi(r), and (iii) being unbinned. We discuss how this estimator would be used in practice, applying it to a sample of mock galaxies selected from the Millennium simulation.

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Nikhil Padmanabhan, Martin White, Daniel J. Eisenstein. 2007-03-23. A Robust Estimator of the Small-Scale Galaxy Correlation Function. https://doi.org/10.1111/j.1365-2966.2007.11554.x

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