A robust estimator of the small-scale galaxy correlation function

A Robust Estimator of the Small-Scale Galaxy Correlation Function

We present a new estimator, ω, 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, witho...

The zero-crossing scale of the galaxy correlation function and the problem of galaxy bias

One of the main problems in the studies of large scale galaxy structures concerns the relation of the correlation properties of a certain population of objects with those of a selected subsample of it, when the selection is performed by considering physical quantities like luminosity or mass. I consider the case where the sampling is defined as in the simplest thresholding selection scheme of t...

Correlation Function of Galaxy Groups

We use the Updated Zwicky Catalog of galaxies (Falco et al. 1999) to generate a catalog of groups, by means of a friend-of-friend algorithm. The groups identified have 4 or more members and a surrounding density contrast, δρ/ρ = 80. They cover the region −4 < δ < 90, |b| > 20 spanning over the radial velocity range of 2000 km s < cz < 15000 km s. The total sample (hereafter GUZC) comprises 517 ...

Comparing estimators of the galaxy correlation function

We present a systematic comparison of some usual estimators of the 2–point correlation function, some of them currently used in Cosmology, others extensively employed in the field of the statistical analysis of point processes. At small scales, it is known that the correlation function follows reasonably well a power–law expression ξ(r) ∝ r−γ. The accurate determination of the exponent γ (the o...

An Alternative Q Chart Incorporating A Robust Estimator Of Scale