来自中微子驱动的对流的高喷射羽毛
Toshiki Sato1,2,3,4, Keiichi Maeda5, Shigehiro Nagataki6,7
1RIKEN, Wako, Japan. toshiki.sato@rikkyo.ac.jp.
Nature
|April 22, 2021
概括
巨大的恒星爆炸可能涉及高的羽毛,正如在Cassiopeia A中观察到的和所暗示的那样. 这些发现支持对流超新星引擎模型, 对于理解恒星进化和元素合成至关重要.
科学领域:
- 天体物理学
- 核天体物理学
- 恒星进化
背景情况:
- 多维模拟表明高浮浮的羽毛有助于巨大的恒星爆炸.
- 超新星残留物呈现出类似预测的气体结构.
- 确认需要在高核燃烧过程中合成的元素 (富含α的结).
研究的目的:
- 检测和确认在Cassiopeia A中通过富含α结合成的特定元素的存在.
- 在巨大的恒星超新星中提供高喷射羽毛的观测证据.
- 验证超新星爆炸和核合成的理论模型.
主要方法:
- 在Cassiopeia A中观察到震荡,高速度,富含铁的喷射物.
- 分析了稳定的 (Ti) 和 (Cr) 与铁 (Fe) 的丰度比率.
- 将观察到的元素比率与核合成模型的预测进行比较,特别是富含α的结.
主要成果:
- 在Cassiopeia A的喷射物中检测到稳定的 (Ti) 和 (Cr).
- 观察到的Ti/Fe和Cr/Fe质量比与预测要求富含α的结相一致.
- 金属成分与中微子处理的预测相匹配,
结论:
- 探测到Ti和Cr提供了强有力的证据,证明卡西欧佩亚A超新星中存在高的喷射羽毛.
- 这些可能在爆炸中增加了冲击波, 支持对流超新星发动机模型.
- 结果证实了中微子加热在巨大的恒星超新星中发挥的作用.
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