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大型紧星系NGC 1277周围的一个红球星团群
Michael A Beasley1,2, Ignacio Trujillo1,2, Ryan Leaman3
1Instituto de Astrofísica de Canarias, Calle Vía Láctea, La Laguna, Spain.
Nature
|March 14, 2018
概括
大型星系通常会在两个阶段形成球状星团,导致红色和蓝色星团. 遗留的星系NGC 1277只显示红色的星团,这表明后来的质量增加很小.
科学领域:
- 银河系天文学
- 星系的形成和演变
- 恒星群体
背景情况:
- 据信,大规模星系的形成是通过两阶段的过程:最初的气体崩和星体爆发,随后的积聚.
- 球状星团系统被认为是类似地形成的,早期的爆发创造了金属丰富的 (红色) 星团,后来的积聚增加了金属贫乏的 (蓝色) 星团.
- 这种双重形成机制预计将导致巨型星系球状星团系统的多模式光学色彩分布.
研究的目的:
- 为了研究大质量遗迹星系候选NGC1277的球状星团系统.
- 测试大质量星系及其球状星团系统的现有二相形成模型.
- 为了确定NGC 1277是否代表一个真正的遗迹星系,形成后的积累最小.
主要方法:
- 进行大质量遗留星系候选NGC1277的光学观测.
- 分析了其球状星团系统的光学颜色分布.
- 使用可能的合并历史的模拟来估计累积的恒星质量.
主要成果:
- NGC 1277 的球状星团系统呈现出单模和完全红色的光学色彩分布.
- 这与其他大质量星系形成鲜明对比,
- 模拟表明NGC 1277的累积恒星质量最多为其总恒星质量的10%.
结论:
- NGC 1277的球状星团系统的红色单模色分布表明其最初的崩后的质量增加是最小的.
- NGC 1277被证实是真正的遗迹星系,支持"红色颗粒"星系的分类.
- 大规模星系中的蓝色球状星团代表了来自较小卫星星系的累积群体.
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