Papers › Separate Universe calibration of the dependence of halo bias on cosmic web anisotropy
Separate Universe calibration of the dependence of halo bias on cosmic web anisotropy
Sujatha Ramakrishnan, Aseem Paranjape
The archive published only this paper's code-link row. Authors, date and abstract are from arXiv's metadata (CC0), read from the Kaggle arXiv metadata snapshot of 2026-09-12 where its title matched the archive's; the title is the archive's.
We use the Separate Universe technique to calibrate the dependence of linear and quadratic halo bias b₁ and b₂ on the local cosmic web environment of dark matter haloes. We do this by measuring the response of halo abundances at fixed mass and cosmic web tidal anisotropy α to an infinite wavelength initial perturbation. We augment our measurements with an analytical framework developed in earlier work which exploits the near-Lognormal shape of the distribution of α and results in very high precision calibrations. We present convenient fitting functions for the dependence of b₁ and b₂ on α over a wide range of halo mass for redshifts 0≤z≤1. Our calibration of b₂(α) is the first demonstration to date of the dependence of non-linear bias on the local web environment. Motivated by previous results which showed that α is the primary indicator of halo assembly bias for a number of halo properties beyond halo mass, we then extend our analytical framework to accommodate the dependence of b₁ and b₂ on any such secondary property which has, or can be monotonically transformed to have, a Gaussian distribution. We demonstrate this technique for the specific case of halo concentration, finding good agreement with previous results. Our calibrations will be useful for a variety of halo model analyses focusing on galaxy assembly bias, as well as analytical forecasts of the potential for using α as a segregating variable in multi-tracer analyses.
Code
Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.
Code Syntology ran Syntology
Not run by Syntology. Nothing on this page verifies that the listed code works.
Results from the paper archive 2025-07-28
No leaderboard rows for this paper in the archive.
Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections