The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function

Details The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function

1999-03-30

arxiv.org/abs/astro-ph/9903462v1

Astrophys.J. 521 (1999) 1

Astronomy and Astrophysics

Astrophysics

41 pages, including 12 Figures. To appear in The Astrophysical Journal, Vol. 521, #1

Scientific paper

10.1086/307531

We calculate perturbatively the normalized spatial skewness, $S_3$, and full three-point correlation function (3PCF), $\zeta$, induced by gravitational instability of Gaussian primordial fluctuations for a biased tracer-mass distribution in flat and open cold-dark-matter (CDM) models. We take into account the dependence on the shape and evolution of the CDM power spectrum, and allow the bias to be nonlinear and/or evolving in time, using an extension of Fry's (1996) bias-evolution model. We derive a scale-dependent, leading-order correction to the standard perturbative expression for $S_3$ in the case of nonlinear biasing, as defined for the unsmoothed galaxy and dark-matter fields, and find that this correction becomes large when probing positive effective power-spectrum indices. This term implies that the inferred nonlinear-bias parameter, as usually defined in terms of the smoothed density fields, might depend on the chosen smoothing scale. In general, we find that the dependence of $S_3$ on the biasing scheme can substantially outweigh that on the adopted cosmology. We demonstrate that the normalized 3PCF, $Q$, is an ill-behaved quantity, and instead investigate $Q_V$, the variance-normalized 3PCF. The configuration dependence of $Q_V$ shows similarly strong sensitivities to the bias scheme as $S_3$, but also exhibits significant dependence on the form of the CDM power spectrum. Though the degeneracy of $S_3$ with respect to the cosmological parameters and constant linear- and nonlinear-bias parameters can be broken by the full configuration dependence of $Q_V$, neither statistic can distinguish well between evolving and non-evolving bias scenarios. We show that this can be resolved, in principle, by considering the redshift dependence of $\zeta$.

Affiliated with

Also associated with

No associations

Rating

The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Power Spectrum, Bias Evolution, and the Spatial Three-Point Correlation Function will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-486631