在经典的nova V339 Del (Nova Delphini 2013) 中进行爆炸性生产
Akito Tajitsu1, Kozo Sadakane2, Hiroyuki Naito3
1Subaru Telescope, National Astronomical Observatory of Japan, 650 North A'ohoku Place, Hilo, Hawaii 96720, USA.
Nature
|February 20, 2015
概括
科学家在新星中检测到-7 (7Be),后者分解为-7 (7Li). 这提供了直接的证据,即新星产生大量的,这是天体物理学中长期存在的问题.
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
- * 恒星进化过程中的恒星进化
背景情况:
- * (Li) 的起源及其生产机制仍然不确定.
- *现有的模型表明大爆炸核合成,宇宙射线,进化恒星,新星和超新星的贡献.
- *以前的研究表明红巨星,非对称巨分支 (AGB) 恒星和新星有显著的产量,但缺乏直接的观测证据.
研究的目的:
- * 为了研究经典新星爆炸中的的产生.
- *为从恒星物体向星际介质的供应提供直接的观测证据.
主要方法:
- *使用近紫外线观测进行经典新星V339 Delphini (Nova Delphini 2013) 的光谱分析.
- *检测了放射性同位素-7 (7Be) 的高度蓝移的共振线.
主要成果:
- * 在2013年Nova Delphini爆炸后38至48天的光谱中检测到单独电离的-7 (7Be).
- *白-7 (7Be) 在新星爆发期间通过α捕获反应 (3He(α,γ) 7Be) 形成.
- *白-7 (7Be) 衰变为-7 (7Li),其半衰期为53.22天.
结论:
- *在经典新星中检测到7Be,直接证明了这些事件中的产生.
- * 这一发现支持理论预测,即新星是银河系的重要来源.
- *这项研究解决了恒星核合成和化学进化的关键问题.
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