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在莱曼-α森林的红移2.3时宇宙膨胀速度的约束
Andrei Cuceu1,2,3,4, Andreu Font-Ribera4,5, Seshadri Nadathur6
1Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Physical review letters
|May 27, 2023
概括
天文学家使用莱曼-阿尔法森林相关性精确测量了红移z=2.3的宇宙膨胀. 这项研究为物质密度和暗能量提供了更严格的约束,为高红移宇宙学开辟了新的途径.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 一个大规模的结构结构.
背景情况:
- 宇宙学参数对于理解宇宙的演变至关重要.
- 之前在高红移 (z>1) 的测量有精度的局限性.
- 莱曼-α (Lyα) 森林相关性为宇宙结构提供了一个探测器.
研究的目的:
- 要确定在z=2.3.3时的膨胀速度和角度直径距离的乘积.
- 限制宇宙学参数,包括物质密度和暗能量状态方程参数.
- 建立Lyα森林相关性作为高红移宇宙学的精确工具.
主要方法:
- 来自斯隆数字天空调查 (SDSS) 的莱曼-α (Lyα) 森林相关性的分析.
- 使用广泛的尺度 (25
- 在哈勃恒定确定之前,将核合成纳入.
主要成果:
- 最精确的测量膨胀率和角度直径距离的产物在z=2.3从大规模结构.
- 物质密度 (Ωm) 确定为0.36±0.03,比声振荡结果密度的两倍.
- 哈勃常数 (H0) 测量为 63.2 ± 2.5 公里/秒/Mpc (仅Lyα) 和 67.2 ± 0.9 公里/秒/Mpc (与其他 SDSS 追踪器).
- 暗能量状态方程参数 (w) 测量为 -0.90 ± 0.12.
结论:
- 莱曼-阿尔法森林相关性提供了一种强大的新方法,用于在高红移时限制宇宙学.
- 该研究产生了高度精确的宇宙学参数,改进了现有的测量.
- 这项研究为探索宇宙膨胀历史开辟了新的前沿.
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