在红移z=4.69的类星体BR1202 - 0725中检测出分子气体
K Ohta1, T Yamada, K Nakanishi
1Department of Astronomy, Kyoto University, Japan.
Nature
|August 1, 1996
概括
研究人员检测到来自遥远的类星体BR1202-0725的一氧化碳 (CO) 排放,红移z=4.69. 这一发现揭示了一个拥有大量分子的巨大星系,表明了重要的早期恒星形成.
科学领域:
- 天文学和天体物理学
- 宇宙气体和银河系进化
背景情况:
- 在早期宇宙中检测出对恒星形成至关重要的分子气体是具有挑战性的.
- 之前在高红移 (z ≈ 2.5) 时检测到的分子气体仅限于重力透镜对象.
研究的目的:
- 报告在高红移时从无线电静静的类星体中检测到一氧化碳 (CO) 排放.
- 调查早期宇宙中分子气体的存在和质量.
主要方法:
- 对一氧化碳 (CO) 排放线的观察.
- 确定类星体BR1202-0725.25的红移.
主要成果:
- 来自无线电静音类星体BR1202-0725在红移z=4.69时的CO排放的检测.
- 估计与类星体相关的分子约有10^11太阳质量.
- 分子气体质量与当今发光星系的恒星质量相当.
结论:
- BR1202-0725代表了早期宇宙中的一个巨大的星系.
- 气体集中在中心,这表明正在发生巨大的恒星形成爆发.
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