在宿主星系中的分子气体中,有一颗具有红移z=6.42的类星体
Fabian Walter1, Frank Bertoldi, Chris Carilli
1National Radio Astronomy Observatory, PO Box 0, Socorro, New Mexico 87801, USA. fwalter@nrao.edu
Nature
|July 25, 2003
概括
这项研究检测到一氧化碳 (CO) 排放,一个分子的标志物,在一个类星体宿主星系在红移z=6.42. 这一发现揭示了早期宇宙中大量的分子气体,这对快速的星系进化至关重要.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
- 银河系的进化 银河系的进化
背景情况:
- 分子 (H2) 对于恒星形成和星系进化至关重要.
- 观察高红移的分子具有挑战性,因为它通常由一氧化碳 (CO) 排放追踪.
- 以前在类星体宿主星系中检测到的CO仅限于z > 2的红移.
研究的目的:
- 为了检测类星体宿主星系中的一氧化碳 (CO) 排放,以创纪录的高红移.
- 为了调查早期宇宙中分子气体的存在和丰富性.
- 了解快速星系形成和演化的条件.
主要方法:
- 利用射电天文学观测来检测二氧化碳排放线.
- 准了类星体SDSS J114816.64 + 525150.3 在红移z = 6.42.4 的位置.
- 分析了光谱数据,以确认存在和测量分子气体的数量.
主要成果:
- 报道了在z = 6.42.2.3处检测到来自类星体SDSS J114816.64 + 525150.3的CO排放.
- 量化了分子 (H2) 质量,大约为2×10^10太阳质量.
- 这次检测发生在宇宙年龄仅为当前年龄的1/16时,即接近宇宙再离子化结束时.
结论:
- 证明了最年轻星系中以重元素丰富的分子气体的快速形成.
- 在高红移时为星系进化模型提供了基本的约束.
- 突出了分子气体在大爆炸后不久的早期星系形成中的重要作用.
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