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A galaxy-halo model of large-scale structure

Mark C. Neyrinck·Andrew J. S. Hamilton·Nickolay Y. Gnedin
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Abstract

We present a new, galaxy-halo model of large-scale structure, in which the galaxies entering a given sample are the fundamental objects. Haloes attach to galaxies, in contrast to the standard halo model, in which galaxies attach to haloes. The galaxy-halo model pertains mainly to the relationships between the power spectra of galaxies and mass, and their cross-power spectrum. With surprisingly little input, an intuition-aiding approximation to the galaxy-matter cross-correlation coefficient R(k) emerges, in terms of the halo mass dispersion. This approximation seems valid to mildly non-linear scales (k < ~3 h/Mpc), allowing measurement of the bias and the matter power spectrum from measurements of the galaxy and galaxy-matter power spectra (or correlation functions). This is especially relevant given the recent advances in precision in measurements of the galaxy-matter correlation function from weak gravitational lensing. The galaxy-halo model also addresses the issue of interpreting the galaxy-matter correlation function as an average halo density profile, and provides a simple description of galaxy bias as a function of scale.

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Mark C. Neyrinck, Andrew J. S. Hamilton, Nickolay Y. Gnedin. 2005-06-10. A galaxy-halo model of large-scale structure. https://doi.org/10.1111/j.1365-2966.2005.09309.x

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