标题： 在场水平上对宇宙学Lyman-$α$森林的建模 显示英文标题

标题： Modeling the Cosmological Lyman-$α$ Forest at the Field Level

摘要： 遥远类星体光谱中的吸收线分布，称为Lyman-$\alpha$（Ly-$\alpha$）森林，是研究高红移和小尺度宇宙学及星际介质的独特探针。正在进行的红移调查的统计能力要求精确的理论工具来模拟Ly-$\alpha$森林。我们通过开发一种解析的、微扰的正向模型，针对给定的宇宙学初始条件，在场水平上预测Ly-$\alpha$森林来应对这一挑战。我们的模型与Sherwood流体动力学模拟相比表现出卓越的性能：它在几兆秒差距的尺度上以百分之一的精度再现通量分布、Ly-$\alpha$- 暗物质晕交叉相关性以及单元计数统计。我们的工作提供了关键的工具，将大尺度上的解析建模与小尺度上的模拟相连接，使得可以从Ly-$\alpha$森林数据中进行场级推断，并为宇宙学分析提供基于模拟的先验信息。这对于通过暗能量光谱仪器实现Ly-$\alpha$森林测量的全部科学潜力尤其及时。 显示英文摘要

摘要： The distribution of absorption lines in the spectra of distant quasars, called the Lyman-$\alpha$ (Ly-$\alpha$) forest, is a unique probe of cosmology and the intergalactic medium at high redshifts and small scales. The statistical power of ongoing redshift surveys demands precise theoretical tools to model the Ly-$\alpha$ forest. We address this challenge by developing an analytic, perturbative forward model to predict the Ly-$\alpha$ forest at the field level for a given set of cosmological initial conditions. Our model shows a remarkable performance when compared with the Sherwood hydrodynamic simulations: it reproduces the flux distribution, the Ly-$\alpha$ - dark matter halo cross-correlations, and the count-in-cell statistics at the percent level down to scales of a few Mpc. Our work provides crucial tools that bridge analytic modeling on large scales with simulations on small-scales, enabling field-level inference from Ly-$\alpha$ forest data and simulation-based priors for cosmological analyses. This is especially timely for realizing the full scientific potential of the Ly-$\alpha$ forest measurements by the Dark Energy Spectroscopic Instrument.