Non-Gaussian halo assembly bias

Journal Article · Thu Jul 01 04:00:00 EDT 2010 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2010/07/013· OSTI ID:22272785

Reid, Beth A.; Verde, Licia ^[1]; Dolag, Klaus ^[2]; Matarrese, Sabino ^[3]; Moscardini, Lauro ^[4]

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1. Institute for Sciences of the Cosmos (ICC), University of Barcelona and IEEC, Barcelona 08028 (Spain)
2. Max Planck Institute for Astrophysics, P.O. Box 1317, D85741 Garching (Germany)
3. Dipartimento di Fisica ''G. Galilei'', Università degli Studi di Padova, via Marzolo 8, I-35131 Padova (Italy)
4. Dipartimento di Astronomia, Università di Bologna, Via Ranzani 1, I-40127 Bologna (Italy)

The strong dependence of the large-scale dark matter halo bias on the (local) non-Gaussianity parameter, f{sub NL}, offers a promising avenue towards constraining primordial non-Gaussianity with large-scale structure surveys. In this paper, we present the first detection of the dependence of the non-Gaussian halo bias on halo formation history using N-body simulations. We also present an analytic derivation of the expected signal based on the extended Press-Schechter formalism. In excellent agreement with our analytic prediction, we find that the halo formation history-dependent contribution to the non-Gaussian halo bias (which we call non-Gaussian halo assembly bias) can be factorized in a form approximately independent of redshift and halo mass. The correction to the non-Gaussian halo bias due to the halo formation history can be as large as 100%, with a suppression of the signal for recently formed halos and enhancement for old halos. This could in principle be a problem for realistic galaxy surveys if observational selection effects were to pick galaxies occupying only recently formed halos. Current semi-analytic galaxy formation models, for example, imply an enhancement in the expected signal of ∼ 23% and ∼ 48% for galaxies at z = 1 selected by stellar mass and star formation rate, respectively.

• OSTI ID: 22272785
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 07 Vol. 2010; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
APPROXIMATIONS
COMPUTERIZED SIMULATION
CORRECTIONS
COSMOLOGY
GALAXIES
MASS
NONLUMINOUS MATTER
RED SHIFT
STAR EVOLUTION
STARS