The dependence of halo bias on age, concentration and spin

DOI: 
10.1093/mnras/stz1338
Publication date: 
01/05/2019
Main author: 
Sato-Polito, Gabriela
IAA authors: 
Prada, Francisco
Authors: 
Sato-Polito, Gabriela;Montero-Dorta, Antonio D.;Abramo, L. Raul;Prada, Francisco;Klypin, Anatoly
Journal: 
Monthly Notices of the Royal Astronomical Society
Refereed: 
Yes
Publication type: 
Article
Pages: 
1570-1579
Abstract: 
Halo bias is the main link between the matter distribution and dark matter haloes. In its simplest form, halo bias is determined by halo mass, but there are known additional dependencies on other halo properties which are of consequence for accurate modeling of galaxy clustering. Here we present the most precise measurement of these secondary-bias dependencies on halo age, concentration, and spin, for a wide range of halo masses spanning from 10<SUP>10.7</SUP> to 10<SUP>14.7</SUP>h<SUP>-1</SUP> M<SUB>☉</SUB>. At the high-mass end, we find no strong evidence of assembly bias for masses above M<SUB>vir</SUB> ̃10<SUP>14</SUP>h<SUP>-1</SUP> M<SUB>☉</SUB>. Secondary bias exists, however, for halo concentration and spin, up to cluster-size haloes, in agreement with previous findings. For halo spin, we report, for the first time, two different regimes: above M<SUB>vir</SUB> ̃ 10<SUP>11.5</SUP>h<SUP>-1</SUP> M<SUB>☉</SUB>, haloes with larger values of spin have larger bias, at fixed mass, with the effect reaching almost a factor 2. This trend reverses below this characteristic mass. In addition to these results, we test, for the first time, the performance of a multi-tracer method for the determination of the relative bias between different subsets of haloes. We show that this method increases significantly the signal-to-noise of the secondary-bias measurement as compared to a traditional approach. This analysis serves as the basis for follow-up applications of our multi-tracer method to real data.
Database: 
ADS
SCOPUS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85071177563&doi=10.1093%2fmnras%2fstz1338&partnerID=40&md5=3a4ed1480d710520dea5710a30f23692
ADS Bibcode: 
2019MNRAS.487.1570S
Keywords: 
methods: numerical;galaxies: formation;galaxies: haloes;dark matter;large-scale structure of Universe;cosmology: theory;Astrophysics - Astrophysics of Galaxies;Astrophysics - Cosmology and Nongalactic Astrophysics