High- to ultrahigh-redshift clustering of halos provides a powerful tool to understand cosmology and galaxy formation. However, theoretical predictions are not firmly established in the first billion years, where current and upcoming surveys are beginning to reach percent-level precision. Here we measure dark matter halo biases at z=6 - 19 from simulation data, and find they are ∼ 3 - 4% higher than canonical results calibrated at low z. We provide an updated linear-bias fit at these early times, reducing the mean systematic offset to <1%. These results will enable robust interpretation of early-Universe galaxy clustering from JWST, Roman, and intensity-mapping surveys.
@article{arxiv.2604.14312,
title = {An Improved Fit for Linear Halo Bias at High Redshift},
author = {Kuan Wang and Julian B. Muñoz and L. Y. Aaron Yung},
journal= {arXiv preprint arXiv:2604.14312},
year = {2026}
}
Comments
6 pages + references, 3 figures, Fig. 3 and Eq. 8 are the main results. To be submitted to PRL, comments are welcome