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arXiv · 2604.14312

An Improved Fit for Linear Halo Bias at High Redshift

Kuan Wang·Julian B. Muñoz·L. Y. Aaron Yung
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Abstract

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 $\sim$ 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.

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Kuan Wang, Julian B. Muñoz, L. Y. Aaron Yung. 2026-04-15. An Improved Fit for Linear Halo Bias at High Redshift. https://arxiv.org/abs/2604.14312

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