FRB DM-星系交叉关联的新测量及其与运动学Sunyaev-Zeldovich效应的首次联合分析
A new measurement of the FRB DM-galaxy cross correlation and a first joint analysis with the kinematic SZ effect
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中文总结 AI 辅助
本研究利用130个FRB测量DM-星系交叉关联，以6.5σ显著性探测信号，否定无反馈情景，首次联合kSZ效应测量大尺度结构生长率，为宇宙重子分布研究提供新探针。
中文摘要 AI 辅助
理解宇宙重子的分布对推进宇宙学和星系形成研究至关重要。已定位的快速射电暴（FRB）是探测弥散气体的极具潜力的新探针，但迄今为止的测量受限于样本量较小。本研究利用130个已定位的FRB（包含来自DSA-110的新光谱宿主红移，以及DESI Legacy Survey亮星系样本）测量FRB色散量（DM）-星系交叉关联，在构型空间和谐波空间中以迄今最高的显著性（6.5σ）探测到该信号。通过与模拟结果和晕模型对比，我们证明该统计量可约束重子反馈的强度；我们的测量以约9σ的置信度否定了气体追踪基础暗物质的无反馈情景。除小尺度反馈外，这也是首次在大于几Mpc的尺度上直接测量电子成团性的研究之一。我们将测量结果与近期运动学Sunyaev-Zeldovich效应（kSZ）研究进行对比，尽管观测方法和样本选择存在差异，但二者表现出良好一致性。最后，我们首次尝试利用FRB打破kSZ光学深度的简并性，联合测量大尺度结构的生长率fσ₈。未来样本中，FRB两点统计将为宇宙重子分布提供高精度约束，并补充其他探针的研究。
英文摘要
Understanding the distribution of cosmic baryons is crucial for advancing cosmology and galaxy formation. Localized Fast Radio Bursts (FRBs) are a promising new probe of the diffuse gas, but measurements thus far have been limited by small sample size. In this work, we measure the FRB dispersion measure (DM)-galaxy cross correlation with 130 localized FRBs, including new spectroscopic host redshifts from the DSA-110, and the DESI Legacy Survey Bright Galaxy Sample. We detect this signal at the highest significance to date ($6.5σ$) in both configuration and harmonic space. By comparing to simulations and a halo model, we demonstrate that this statistic can constrain the strength of baryonic feedback. Our measurements disfavor a no-feedback scenario in which gas traces the underlying dark matter at $\sim\,9σ$. In addition to small scale feedback, this represents one of the first direct measurements of the clustering of electrons on scales larger than a few Mpc. We compare our measurement to recent kinematic Sunyaev-Zeldovich effect (kSZ) studies, which show good agreement despite the differences in observational methods and sample selection. Finally, we make a first attempt at breaking the kSZ optical depth degeneracy with FRBs, jointly measuring the growth rate of large-scale structure $fσ_8$. With future samples, FRB two-point statistics will provide precision constraints on the distribution of cosmic baryons and complement other probes.
