微波背景温度在从H2O吸收的6.34的红移
Dominik A Riechers1, Axel Weiss2, Fabian Walter3,4
1I. Physikalisches Institut, Universität zu Köln, Köln, Germany. riechers@ph1.uni-koeln.de.
Nature
|February 3, 2022
概括
科学家测量了宇宙微波背景温度的红移6.34使用水分子吸收在遥远的星系爆发. 这一发现支持标准宇宙学模型
科学领域:
- 宇宙学
- 天体物理学
- 光谱学
背景情况:
- 宇宙微波背景 (CMB) 温度测量对于了解早期宇宙至关重要.
- 之前的CMB温度估计仅限于较低的红移 (z < 3. 3),有些则取决于模型.
- 标准的Lambda冷暗物质 (ΛCDM) 模型预测了CMB温度和红移之间的特定关系 (T_CMB (1+z)).
研究的目的:
- 在较高红移 (z = 6.34) 时测量CMB温度,以测试LCDM模型.
- 探测宇宙中物质主导的时代.
- 调查一个遥远的星系的热特性.
主要方法:
- 在恒星爆发星系HFLS3中观察到的小毫米线吸收.
- 使用CMB作为吸收测量的背景源.
- 分析了由于恒星爆发活动而导致的水分子的辐射.
主要成果:
- 在z=6.34时检测到水分子对CMB的吸收.
- 在z=6.34时推断CMB温度为16.430.2 K (1σ).
- 由于辐射送,观察到水分子在CMB温度以下的冷却.
结论:
- 在z=6.34时测量到的CMB温度与LCDM宇宙学预测的 (1+z) 缩放一致.
- 这项研究将直接的CMB温度测量扩展到显著更高的红移.
- 星系中的星爆活动可以影响相对于CMB的分子线的激发.
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