来自SN2014J的早期56Ni衰变马射线表明了一个不寻常的爆炸
Roland Diehl1, Thomas Siegert2, Wolfgang Hillebrandt3
1Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse 1, D-85741 Garching, Germany rod@mpe.mpg.de.
概括
在超新星SN2014J中早期发现放射性-56表明发生了不对称的爆炸. 这一发现挑战了Ia型超新星的标准模型,表明-56.6的分布不均.
科学领域:
- * 天体物理学 * 天体物理学
- * 核天体物理学 核天体物理学
背景情况:
- *Ia型超新星起源于涉及碳氧白矮星的双星系统.
- *这些爆炸通常产生大约0.5太阳质量的放射性-56,通常深深嵌入喷射物中.
研究的目的:
- * 为了研究超新星SN2014J中放射性-56衰变的早期马射线发射.
- * 了解早期-56检测对Ia型超新星爆炸不对称性和标准模型的影响.
主要方法:
- *检测到158和812千电子伏特的玛射线线,表明-56的衰变.
- * 检测时间大约在爆炸后20天,比预期早得多.
主要成果:
- *观察到来自-56衰变的早期马射线信号,大约在爆炸后8.8天.
- *检测到的流量水平相当于预期-56总量的约10%,比典型的几周时间表早得多.
- *早期检测意味着非球形爆炸机制和-56.6的向外分布.
结论:
- *在SN2014J中早期和空间分布的-56检测挑战了Ia型超新星中球形对称性的假设.
- *一个合理的机制涉及从伴星中增加,形成爆炸带,触发超新星并不均地分配-56.
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