一个强度图的21厘米的排放在红移z大约0.8的强度图
Tzu-Ching Chang1, Ue-Li Pen, Kevin Bandura
1IAA, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan. tchang@cita.utoronto.ca
Nature
|July 24, 2010
概括
天文学家在宇宙网络中检测到来自中性的21厘米总发光,红移值高达1.12. 这一突破使得使用21厘米强度映射对暗能量进行新的研究成为可能.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 无线电天文学 无线电天文学
背景情况:
- 从中性探测器发出的21厘米的无线电辐射探测宇宙暗能量.
- 光学宇宙学面临的挑战在红移z~1由于大气红外不透明.
- 之前的21厘米排放检测仅限于z = 0.24.
研究的目的:
- 开发一个三维的21厘米强度场在红移z=0.53到1.12.
- 为了研究21厘米强度绘图在暗能量研究中的潜力.
- 为了克服在更高红移时检测单个星系的局限性.
主要方法:
- 从大约1万个星系中添加中性 (H i) 排放.
- 使用来自DEEP2光学星系红移调查的数据.
- 测量宇宙网络中未解决的星系的聚合辐射.
主要成果:
- 一个三维的21厘米强度场成功生成了z = 0.53到1.12.
- 来自中性的21厘米总发光被检测到具有约4sigma的显著性.
- 证明了21厘米强度绘图的可行性,用于宇宙学研究.
结论:
- 聚合21厘米的辐射是可行的探测暗能量在更高的红移.
- 这种技术克服了在特定红移范围内的光学宇宙学的局限性.
- 开辟了绘制宇宙网络和理解宇宙加速的新途径.
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