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Home List of Titles Three-point correlation functions of SDSS galaxies: constraining galaxy-mass bias
Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/206312
- Three-point correlation functions of SDSS galaxies: constraining galaxy-mass bias
- McBride, Cameron K.; Connolly, Andrew J.; Gardner, Jeffrey P.; Scranton, Ryan; Scoccimarro, Roman; Berlind, Andreas A.; Marin, Felipe; Schneider, Donald P.
- We constrain the linear and quadratic bias parameters from the configuration dependence of the three-point correlation function (3PCF) in both redshift and projected space, utilizing measurements of spectroscopic galaxies in the Sloan Digital Sky Survey Main Galaxy Sample. We show that bright galaxies (Mr < –21.5) are biased tracers of mass, measured at a significance of 4.5σ in redshift space and 2.5σ in projected space by using a thorough error analysis in the quasi-linear regime (9-27 h –1 Mpc). Measurements on a fainter galaxy sample are consistent with an unbiased model. We demonstrate that a linear bias model appears sufficient to explain the galaxy-mass bias of our samples, although a model using both linear and quadratic terms results in a better fit. In contrast, the bias values obtained from the linear model appear in better agreement with the data by inspection of the relative bias and yield implied values of σ8 that are more consistent with current constraints. We investigate the covariance of the 3PCF, which itself is a measurement of galaxy clustering. We assess the accuracy of our error estimates by comparing results from mock galaxy catalogs to jackknife re-sampling methods. We identify significant differences in the structure of the covariance. However, the impact of these discrepancies appears to be mitigated by an eigenmode analysis that can account for the noisy, unresolved modes. Our joint analysis of both redshift space and projected measurements allows us to identify systematic effects affecting constraints from the 3PCF.
- Publication type
- Journal article
- Research centre
- Swinburne University of Technology. Faculty of Information and Communication Technologies. Centre for Astrophysics and Supercomputing
- Astrophysical Journal, Vol. 739, no. 2 (Oct 2011), article no. 85
- Publication year
- FOR Code(s)
- 0201 Astronomical and Space Sciences; 0305 Organic Chemistry; 0306 Physical Chemistry (Incl. Structural)
- Cosmological observations; Galaxies; Large-scale structure of Universe; Statistics
- Institute of Physics Publishing
- Publisher URL
- Copyright © 2011 The American Astronomical Society. All rights reserved.
- Peer reviewed