量子星中发生的一次千帕塞克级超级恒星爆炸,发生在大爆炸后不到1千亿年
Fabian Walter1, Dominik Riechers, Pierre Cox
1Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany. walter@mpia.de
Nature
|February 6, 2009
概括
早期的星系在很大区域形成恒星,与局部星系不同. 这项研究揭示了z=6.42类星体宿主星系中恒星形成的跨度为750 pc,这表明巨大的球形结构的快速增长.
科学领域:
- 天文学和天体物理学
- 太空进化的宇宙进化
- 银河系的形成 星系的形成
背景情况:
- 类星体是极其发光的活跃星系核,由超大质量黑洞提供动力.
- 早期宇宙的星系表现出高恒星形成率,但这种活动的规模尚不清楚.
- 当地发光星系显示紧的星爆 (<100 pc),与早期星系形成模型形成鲜明对比.
研究的目的:
- 为了研究一个高红移类星 (SDSS J114816.64+525150.3) 的宿主星系中恒星形成的空间分布.
- 为了比较早期宇宙中的恒星形成尺度与当地星系中观察到的恒星形成尺度.
- 了解巨大的银河系结构形成的含义.
主要方法:
- 来自宿主星系的[C ii]辐射的空间分辨率成像.
- 分析红外发光度以估计恒星形成活动.
- 观察到的尺度与局部星系基准 (例如Arp 220) 的比较.
主要成果:
- 量子星宿主星系中的恒星形成气体分布在一个半径约为750 pc的区域内.
- 恒星形成速度的表面密度是~1,000年{-1) kpc{-2),可与局部星爆的峰值值相比较.
- 形成恒星的区域比局部发光星系大得多 (大小有两倍).
结论:
- 早期宇宙中的恒星形成比局部宇宙中发生的规模要大得多.
- 这种广泛,充满活力的恒星形成可能是早期星系中构建巨大的球状元件的关键过程.
- 这些发现挑战了关于原始星系中紧星爆的先前假设.
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