2020/06/23 by Rafael García, Rafael Garcia, Eduardo Rozo +3 · 1 citation
Environmental Science · Mathematics · Physics and Astronomy · #Approx #Astrophysics #Astrophysics and Cosmic Phenomena #Boundary (topology) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Halo effect #Mathematical analysis #Mathematics #Multiplicative function #Physics #RADIUS #Remote Sensing in Agriculture #astro-ph.CO
paper · pdf · doi:10.1093/mnras/stab1317
12 pages, 5 figures
arxiv created 2020/06/23 · openalex created_date 2020/06/25 · openalex publication_date 2021/05/07 · arxiv updated 2021/05/26 · openalex updated_date 2026/08/05
ABSTRACT We present a model for the halo–mass correlation function that explicitly incorporates halo exclusion and allows for a redefinition of the halo boundary in a flexible way. We assume that haloes trace mass in a way that can be described using a single scale-independent bias parameter. However, our model exhibits scale-dependent biasing due to the impact of halo-exclusion, the use of a ‘soft’ (i.e. not infinitely sharp) halo boundary, and differences in the one halo term contributions to ξhm and ξmm. These features naturally lead us to a redefinition of the halo boundary that lies at the ‘by eye’ transition radius from the one-halo to the two-halo term in the halo–mass correlation function. When adopting our proposed definition, our model succeeds in describing the halo–mass correlation function with ≈ 2 \rm per cent residuals over the radial range 0.1 h−1 Mpc < r < 80 h−1 Mpc, and for halo masses in the range 1013 h−1 M⊙ < M < 1015 h−1 M⊙. Our proposed halo boundary is related to the splashback radius by a roughly constant multiplicative factor. Taking the 87 percentile as reference we find rt/Rsp ≈ 1.3. Surprisingly, our proposed definition results in halo abundances that are well described by the Press–Schechter mass function with δsc = 1.449 ± 0.004. The clustering bias parameter is offset from the standard background-split prediction by ≈ 10 \rm per cent - 15 \rm per cent. This level of agreement is comparable to that achieved with more standard halo definitions.