迈向精确运动学Sunyaev-Zel'dovich宇宙学——1. 一圈阶的物质-动量双谱
Toward Precision Kinetic Sunyaev-Zel'dovich Cosmology---1. The Matter - Momentum Bispectrum at One-Loop Order
浏览论文内容
中文总结 AI 辅助
本文利用有效场论框架计算一圈阶物质-动量双谱，以解决kSZ效应测量中大小尺度简并问题，并与模拟吻合至5%，推动精确kSZ宇宙学发展。
中文摘要 AI 辅助
运动学Sunyaev-Zeldovich（kSZ）效应是自由电子动量场的灵敏探针，能够触及与大尺度宇宙学和小尺度天体物理学相关的空间相关性。精确的kSZ测量将为约束暴胀物理和等效原理违背提供稳健的渠道，同时表征小尺度气体分布及相关的重子反馈。然而，用于宇宙学应用的稳健kSZ测量具有挑战性，因为大尺度信息的主要来源与未知的小尺度动力学在简并组合中卷积在一起。在本文中，我们利用有效场论（EFT）框架应对这一挑战，该框架为处理小尺度动力学对大尺度结构的影响提供了一种原则性方法。提取kSZ信号可以重新表述为对一圈阶星系-星系-电子动量双谱的测量。我们在此计算了该双谱的纯暗物质版本，并将其与模拟进行比较。我们推导了捕捉小尺度反作用的EFT逆项，发现其中两个具有横向方向。一个横向逆项完全由速度场的涡度产生。我们对双谱偶极子的计算与模拟数据在$k_{\rm max}=0.23~\iM$范围内吻合至$5\\%$，这显著大于树级理论的适用范围，后者在$k_{\rm max}=0.07~\iM$（红移$z=0.5$）之外失效。对于与测量kSZ场相关的投影动量场计算的双谱，我们发现了类似的$k_{\rm max}$，并首次从模拟中探测到横向逆项。我们的结果表明，一圈阶双谱计算可以在推进kSZ宇宙学中发挥重要作用。
英文摘要
The kinetic Sunyaev-Zeldovich (kSZ) effect is a sensitive probe of the free-electron momentum field, tapping into spatial correlations relevant for both large-scale cosmology and smaller-scale astrophysics. Precision kSZ measurements will provide a robust channel for constraining inflationary physics and equivalence principle violation, while simultaneously characterizing the small-scale gas distribution and associated baryonic feedback. However, robust kSZ measurement for cosmological applications is challenging, as the primary source of large-scale information is convolved with unknown small-scale dynamics in a degenerate combination. In this paper we address this challenge using the Effective Field Theory (EFT) framework that provides a principled way of treating the effects of small-scale dynamics on large scale-structure. Extracting the kSZ signal can be reformulated as a measurement of the one-loop galaxy-galaxy-electron momentum bispectrum. We compute here a pure dark matter version of this bispectrum in EFT and compare it to simulations. We derive the EFT counterterms that capture small-scale backreaction and find that two of them acquire a transverse direction. One transverse counterterm gets generated entirely by the vorticity of the velocity field. Our computation of the bispectrum dipole agrees with simulation data to 5% up to k_max = 0.23 h/Mpc, which is significantly larger than the reach of tree level theory, which breaks down beyond k_max = 0.07 h/Mpc (at redshift z = 0.5). For the bispectrum computed with the projected momentum field, relevant to measuring the kSZ field, we find a similar k_max, and make the first detection of the transverse counterterms from simulations. Our results suggest that one-loop bispectrum computations can play an important role in advancing kSZ cosmology.
发表机构
- Massachusetts Institute of Technology（麻省理工学院）
- MIT Kavli Institute for Astrophysics and Space Research（麻省理工学院卡弗里天体物理与空间研究所）
- Center for Theoretical Physics – a Leinweber Institute, Massachusetts Institute of Technology（麻省理工学院莱因韦伯理论物理中心）
机构由 AI 辅助整理，请以论文原文为准。
