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An Inversion Method for Measuring Beta in Large Redshift Surveys

Stephen D. Landy·Alexander S. Szalay
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Abstract

A precision method for determining the value of Beta= Omega_m^{0.6}/b, where b is the galaxy bias parameter, is presented. In contrast to other existing techniques that focus on estimating this quantity by measuring distortions in the redshift space galaxy-galaxy correlation function or power spectrum, this method removes the distortions by reconstructing the real space density field and determining the value of Beta that results in a symmetric signal. To remove the distortions, the method modifies the amplitudes of a Fourier plane-wave expansion of the survey data parameterized by Beta. This technique is not dependent on the small-angle/plane-parallel approximation and can make full use of large redshift survey data. It has been tested using simulations with four different cosmologies and returns the value of Beta to +/- 0.031, over a factor of two improvement over existing techniques.

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Stephen D. Landy, Alexander S. Szalay. 2002-04-29. An Inversion Method for Measuring Beta in Large Redshift Surveys. https://doi.org/10.1086/342790

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