在一个遥远的类星体中发生大规模星体爆发的基本特征
P Solomon1, P Vanden Bout, C Carilli
1Department of Physics and Astronomy, SUNY at Stony Brook, Stony Brook, New York 11794, USA. psolomon@sbastk.ess.sunysb.edu
Nature
|December 12, 2003
概括
高红移类星体有大量的密集分子气体,由化 (HCN) 观测揭示出来. 这种密集的气体为巨大的星爆提供燃料,有助于形成类星体.
科学领域:
- 天文学和天体物理学
- 宇宙气体动力学 宇宙气体动力学
- 银河系的进化 银河系的进化
背景情况:
- 高红移的星系 (z > 2) 通过一氧化碳 (CO) 排放显示出大量的分子气体.
- 活跃的星系核 (AGN) 在这些星系中很常见,由超大质量黑洞提供动力.
- 这些星系中高红外发光的来源 (AGN,恒星形成或两者兼而有之) 是一个关键问题.
研究的目的:
- 为了研究高红移星系中密集分子气体的存在和特性.
- 为了确定密集气体对恒星形成和红外发光的贡献.
- 使用化 (HCN) 作为密集气体的标记物.
主要方法:
- 在红移z = 2.5579.9时观察到来自"三叶草"类星体的HCN辐射.
- 分析HCN线光度以推断气体特性.
- 与CO观测和恒星形成模型进行比较.
主要成果:
- 检测来自"三叶草"类星体的HCN排放.
- HCN线的亮度表明有100亿个太阳质量的非常密集的气体.
- 这种密集的气体是巨大的星爆的关键特征.
结论:
- "三叶草"类星体主持着由密集的分子气体为燃料的显著星体爆发.
- 星爆和活跃的银河系核都对类星体的高红外发光量有所贡献.
- 在高红移星系中,HCN是密集气体的有效追踪器,对恒星形成至关重要.
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