Secondary halo bias through cosmic time II: Reconstructing halo properties using clustering information

TL;DR

This paper introduces a novel algorithm that reconstructs dark matter halo properties using clustering data, improving the accuracy of mock galaxy catalogs by capturing both primary and secondary bias effects.

Contribution

The authors develop a hierarchical, multi-scale method to assign halo properties based solely on clustering information, enhancing the realism of mock catalogs compared to previous approaches.

Findings

Reconstructed halo properties match large-scale clustering signals from N-body simulations.

The method accurately reproduces both primary and secondary bias effects.

Improved high-mass halo property assignment over existing methods.

Abstract

When constructing galaxy mock catalogs based on suits of dark matter halo catalogs generated with approximated, calibrated or machine-learning approaches, the assignment of intrinsic properties for such tracers is a step of paramount relevance, given that these can shape the abundance of mock galaxy cluster and the spatial distribution of mock galaxies. We explore the possibility to assign properties of dark matter halos within the context of calibrated/learning approaches, explicitly using clustering information. The goal is to retrieve the correct signal of primary and secondary large-effective bias as a function of properties reconstructed solely based on phase-space properties of the halo distribution and dark matter density field. The algorithm reconstructs a set halo properties (such as virial mass, maximum circular velocity, concentration and spin) constraint to reproduce both primary and secondary (or assembly) bias. The key ingredients of the algorithm are the implementation of individually-assigned large-scale effective bias, a multi-scale approach to account for halo exclusion and a hierarchical assignment of halo properties. The method facilitates the assignment of halo properties aiming at replicating the large-scale effective bias, both primary and secondary. This improves over over previous methods found in the literature, especially at the high mass population. We have designed an strategy to reconstruct the main properties of dark matter halos obtained by calibrated/learning algorithms, in a way that the expected one and two-point statistics (on large scales) replicates the signal from detailed N-body simulations. We encourage the application of this strategy (or the implementation of our algorithm) for the generation of mock catalogs of dark matter halos based on approximated methods.