在银河系NGC 7793中的一个强大的微类星体周围,一个300帕塞克长的喷气式膨胀泡
Manfred W Pakull1, Roberto Soria, Christian Motch
1University of Strasbourg, CNRS UMR 7550, Observatoire Astronomique, 11 rue de l'Université, F67000 Strasbourg, France. manfred.pakull@astro.unistra.fr
Nature
|July 9, 2010
概括
我们在NGC 7793中发现了一个微类星,S26,它具有强大的喷气,类似于SS433,但更大. 它的喷射比它的X射线核辐射有1万倍的能量.
科学领域:
- * 天体物理学 * 天体物理学
- *高能天体物理学 *高能天体物理学
- * 黑洞物理学 黑洞物理学
背景情况:
- * 黑洞积聚状态接近或高于爱丁顿发光度,由于源稀有,人们对其了解甚少.
- * 超发光X射线源 (ULXs) 是发光的核外黑洞,可能以超级埃丁顿速度增长.
- * 带有稳定喷射的微类星体比ULX的亮度小,而ULX通常缺乏协同喷射的证据.
研究的目的:
- * 为了研究NGC 7793.3中的大星云S26的性质.
- * 为了确定S26是否由一个黑洞提供动力,并配合喷气.
- * 描述S26的功率输出和结构,并将其与已知的天体物理来源进行比较.
主要方法:
- *分析S26星云及其核心的X射线和光学数据.
- * 确定喷气机的机械功率输出.
- *对S26进行结构分析,将其与Fanaroff-Riley II型活跃星系和微类星系进行比较.
主要成果:
- * S26由一个黑洞提供动力,产生一对结合的喷气.
- *喷射器的机械功率大约是X射线核辐射的几 10^40 erg s^-1,~10^4倍.
- * S26表现出Fanaroff-Riley II型结构,包括X射线热点,无线电叶和X射线.
结论:
- * S26是一个强大的微类星体,比SS433.3大得多,更有活力.
- * S26的大部分喷气功率在叶片内的热粒子中消散,而不是相对论电子.
- * 这一发现为超级埃丁顿速率的黑洞积累状态提供了新的见解.
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