English

A New Wavelet Scattering Transform-Based Statistic for Cosmological Analysis of Large-Scale Structure

Cosmology and Nongalactic Astrophysics 2025-12-01 v3

Abstract

Large-scale structure (LSS) analysis in galaxy surveys is a powerful cosmological probe but is limited by tracer bias, which can obscure underlying information and weaken parameter constraints. Existing methods either model bias or restrict analyses to low-density regions, yet their sensitivity to bias remains poorly understood. We propose a novel method based on the wavelet scattering transform (WST) to distinguish LSS across cosmological models while mitigating tracer bias. Central to our approach are the WST mm-mode ratios, RwstR^{\rm wst}, a new statistical measure, and a high-density apodization preprocessing that smoothly rescales extreme values. We use a reduced chi-square to assess the cosmological parameter constraints and find that RwstR^{\rm wst}, in the scale range j[3,7]j \in [3,7], achieves χν,cos26\chi^2_{\nu, \rm cos} \approx 6 for cosmology while maintaining χν,bias21\chi^2_{\nu, \rm bias} \sim 1--a regime unattained by other statistics. RwstR^{\rm wst} thus provides robust cosmological sensitivity with effective bias mitigation for future surveys.

Keywords

Cite

@article{arxiv.2505.14400,
  title  = {A New Wavelet Scattering Transform-Based Statistic for Cosmological Analysis of Large-Scale Structure},
  author = {Zhujun Jiang and Xiaolin Luo and Wenying Du and Zhiwei Min and Fenfen Yin and Longlong Feng and Jiacheng Ding and Le Zhang and Xiao-Dong Li},
  journal= {arXiv preprint arXiv:2505.14400},
  year   = {2025}
}

Comments

16 pages, 5 figures

R2 v1 2026-07-01T02:25:12.993Z