Marked statistics across the cosmic web: Environmental dependent clustering in modified gravity simulations

TL;DR

This study demonstrates that incorporating environmental information, especially from filaments, into marked correlation functions significantly enhances the ability to detect and constrain modified gravity effects in cosmic structure formation.

Contribution

The paper introduces a multi-scale environment-dependent marked correlation function analysis applied to modified gravity simulations, highlighting the increased information content from environmental structures.

Findings

Modified gravity impacts are strongest in nodes and filaments.

Environmental information doubles the constraining power of galaxy clustering tests.

Including filament environments significantly improves detection of modified gravity signals.

Abstract

We study environment-dependent clustering using the marked correlation function applied to Hu-Sawicki $f(R)$ modified gravity simulations. This gravity theory enriches the structure formation by enhancing gravity in a scale-dependent form. By employing a multi-scale cosmic structure finder algorithm, we define the cosmic environments divided in: nodes, filaments, walls and voids. We find a stronger impact of modified gravity in nodes and filament, which together dominate the information content by more than a factor of four relative to other environments. Combining environmental information further enhances the expected signal-to-noise ratio for CMASS- and DESI-like mock samples, particularly in configurations including filaments. Overall, marked correlation functions that incorporate environmental structure increase the information content by about a factor of two compared to standard density-based marks applied to the full galaxy sample. These results demonstrate the importance of environmental information, especially from filaments, in improving the constraining power of galaxy clustering tests of modified gravity.