### Abstract

We show that current surveys have at least as much signal to noise in higher-order statistics as in the power spectrum at weakly nonlinear scales. We discuss how one can use this information to determine the mean of the galaxy halo-occupation distribution (HOD) using only large-scale information, through galaxy bias parameters determined from the galaxy bispectrum and trispectrum. After introducing an averaged, reasonably fast to evaluate, trispectrum estimator, we show that the expected errors on linear and quadratic bias parameters can be reduced by at least 20%-40%. Also, the inclusion of the trispectrum information, which is sensitive to "three-dimensionality" of structures, helps significantly in constraining the mass dependence of the HOD mean. Our approach depends only on adequate modeling of the abundance and large-scale clustering of halos and thus is independent of details of how galaxies are distributed within halos. This provides a consistency check on the traditional approach of using two-point statistics down to small scales, which necessarily makes more assumptions. We present a detailed forecast of how well our approach can be carried out in the case of the Sloan Digital Sky Survey (SDSS).

Original language | English (US) |
---|---|

Article number | 063001 |

Pages (from-to) | 1-13 |

Number of pages | 13 |

Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |

Volume | 71 |

Issue number | 6 |

DOIs | |

State | Published - Mar 15 2005 |

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### ASJC Scopus subject areas

- Physics and Astronomy(all)
- Nuclear and High Energy Physics
- Mathematical Physics

### Cite this

*Physical Review D - Particles, Fields, Gravitation and Cosmology*,

*71*(6), 1-13. [063001]. https://doi.org/10.1103/PhysRevD.71.063001

**Galaxy bias and halo-occupation numbers from large-scale clustering.** / Sefusatti, Emiliano; Scoccimarro, Román.

Research output: Contribution to journal › Article

*Physical Review D - Particles, Fields, Gravitation and Cosmology*, vol. 71, no. 6, 063001, pp. 1-13. https://doi.org/10.1103/PhysRevD.71.063001

}

TY - JOUR

T1 - Galaxy bias and halo-occupation numbers from large-scale clustering

AU - Sefusatti, Emiliano

AU - Scoccimarro, Román

PY - 2005/3/15

Y1 - 2005/3/15

N2 - We show that current surveys have at least as much signal to noise in higher-order statistics as in the power spectrum at weakly nonlinear scales. We discuss how one can use this information to determine the mean of the galaxy halo-occupation distribution (HOD) using only large-scale information, through galaxy bias parameters determined from the galaxy bispectrum and trispectrum. After introducing an averaged, reasonably fast to evaluate, trispectrum estimator, we show that the expected errors on linear and quadratic bias parameters can be reduced by at least 20%-40%. Also, the inclusion of the trispectrum information, which is sensitive to "three-dimensionality" of structures, helps significantly in constraining the mass dependence of the HOD mean. Our approach depends only on adequate modeling of the abundance and large-scale clustering of halos and thus is independent of details of how galaxies are distributed within halos. This provides a consistency check on the traditional approach of using two-point statistics down to small scales, which necessarily makes more assumptions. We present a detailed forecast of how well our approach can be carried out in the case of the Sloan Digital Sky Survey (SDSS).

AB - We show that current surveys have at least as much signal to noise in higher-order statistics as in the power spectrum at weakly nonlinear scales. We discuss how one can use this information to determine the mean of the galaxy halo-occupation distribution (HOD) using only large-scale information, through galaxy bias parameters determined from the galaxy bispectrum and trispectrum. After introducing an averaged, reasonably fast to evaluate, trispectrum estimator, we show that the expected errors on linear and quadratic bias parameters can be reduced by at least 20%-40%. Also, the inclusion of the trispectrum information, which is sensitive to "three-dimensionality" of structures, helps significantly in constraining the mass dependence of the HOD mean. Our approach depends only on adequate modeling of the abundance and large-scale clustering of halos and thus is independent of details of how galaxies are distributed within halos. This provides a consistency check on the traditional approach of using two-point statistics down to small scales, which necessarily makes more assumptions. We present a detailed forecast of how well our approach can be carried out in the case of the Sloan Digital Sky Survey (SDSS).

UR - http://www.scopus.com/inward/record.url?scp=18444383344&partnerID=8YFLogxK

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U2 - 10.1103/PhysRevD.71.063001

DO - 10.1103/PhysRevD.71.063001

M3 - Article

VL - 71

SP - 1

EP - 13

JO - Physical review D: Particles and fields

JF - Physical review D: Particles and fields

SN - 1550-7998

IS - 6

M1 - 063001

ER -