探测来自星爆星系的玛射线
F Acero1, F Aharonian, A G Akhperjanian
1Laboratoire de Physique Théorique et Astroparticules, Université Montpellier 2, CNRS/IN2P3, CC 70, Place Eugène Bataillon, F-34095 Montpellier Cedex 5, France.
Science (New York, N.Y.)
|September 26, 2009
概括
从星爆星系NGC 253中检测到的高能马射线表明宇宙射线密度明显更高. 这表明星爆星系是强大的宇宙射线工厂,能有效地将能量转化为马射线.
科学领域:
- 天体物理学 天体物理学
- 宇宙射线物理学 宇宙射线物理学
- 高能天文学 高能天文学
背景情况:
- 星爆星系经历了强烈的恒星形成和超新星.
- 理论上说,超新星残留物可以使宇宙射线加速到高能量 (~10^15 eV).
- 马射线作为这些有能量宇宙射线的标记物.
研究的目的:
- 为了检测来自星爆星系NGC 253的马射线.
- 为了研究星爆星系中宇宙射线的密度和行为.
- 为了比较NGC 253中的宇宙射线属性与银河系中的属性.
主要方法:
- 使用了高能立体系统 (H.E.S.S.) 阵列 阵列 阵列
- 采用成像大气切伦科夫望远镜用于马射线检测.
- 分析了高于220亿电子伏特的马射线流.
主要成果:
- 从NGC 253上检测到F = (5.5 ± 1.0(stat) ± 2.8(sys)) x 10^-13 cm^-2 s^-1的马射线流.
- 推断NGC 253的宇宙射线密度大约是银河系中心的1000倍.
- 观察到,与我们的银河系相比,NGC 253中转化为马射线的宇宙射线能量比例是NGC 253的五倍.
结论:
- 像NGC 253这样的星爆星系是高能宇宙射线的重要来源.
- 观测到的马射线辐射为这些环境中有效的宇宙射线加速提供了有力的证据.
- NGC 253 作为研究极端宇宙射线物理学的重要实验室.
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