发表机构
National Astronomical Observatories, Chinese Academy of Sciences; School of Astronomy and Space Science, University of Chinese Academy of Sciences (UCAS); Asia Pacific Center for Theoretical Physics (APCTP); Department of Physics, College of Sciences, Northeastern University（中国科学院国家天文台; 中国科学院大学天文与空间科学学院; 亚太理论物理中心; 东北大学理学院物理系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过模拟ACT和MeerKAT观测，预测平方kSZ与平方HI强度场的互相关信号，并证明其具有约3-4的信噪比，可实现未来联合观测中的探测。
AI 中文摘要
动力学Sunyaev--Zel'dovich（kSZ）效应探测自由电子的视线方向动量，但其黑体谱和依赖于速度的符号使其难以分离，并导致与密度示踪物的常规互相关消失。在本工作中，我们利用由Jiutian-1G模拟光锥构建的模拟ACT和MeerKAT观测，研究了平方kSZ场与投影平方HI强度场的互相关。我们在$13.5^\circ\times13.5^\circ$的视场内生成基于暗晕的kSZ图和类MeerKAT的HI亮度温度立方体。模拟包含了ACT波束平滑和有效内部线性组合噪声，以及频率相关的MeerKAT波束、扫描策略、制图和非均匀热噪声。我们分析了仅信号、理想化振幅重建和维纳滤波的kSZ图。所得的平方场互相关具有约$3$-$4$的诊断性累积信噪比。我们的图级结果证明了在未来的联合ACT--MeerKAT观测中，${\rm kSZ}^2\times {\rm HI}^2$相关的可探测性。
英文摘要
The kinetic Sunyaev--Zel'dovich (kSZ) effect probes the line-of-sight momentum of free electrons, but its blackbody spectrum and velocity-dependent sign make it difficult to isolate and cause conventional cross-correlations with density tracers to vanish. In this work, we investigate the cross-correlation of the squared kSZ field with the projected squared HI intensity field using mock ACT and MeerKAT observations constructed from a Jiutian-1G simulation lightcone. We generate halo-based kSZ maps and MeerKAT-like HI brightness-temperature cubes over a $13.5^\circ\times13.5^\circ$ field. The simulations incorporate ACT beam smoothing and effective internal-linear-combination noise, together with the frequency-dependent MeerKAT beam, scanning strategy, map-making, and inhomogeneous thermal noise. We analyze signal-only, idealized amplitude-reconstructed, and Wiener-filtered kSZ maps. The resulting squared-field cross-correlations have diagnostic cumulative signal-to-noise ratios of approximately $3$-$4$. Our map-level results demonstrate the detectability of the ${\rm kSZ}^2\times {\rm HI}^2$ correlation in future joint ACT--MeerKAT observations.
Comments27 pages, 9 figures, 3 tables
