arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2101.09618astro-ph.HE
收藏

不对称中微子发射对核心坍缩超新星II核合成的影响--祖先的依赖性--

The impact of asymmetric neutrino emissions on nucleosynthesis in core-collapse supernovae II -- progenitor dependences --

Shin-ichiro Fujimoto, Hiroki Nagakura

摘要:

研究了质量范围为9.5 ~ 25 $M_{\odot}$的前体超新星核心坍缩(CCSNe)中不对称中微子发射对爆炸性核合成的影响。我们进行轴对称,流体动力学模拟的CCSN爆炸与一个简化的中微子输运,其中施加的$ν_{\rm e}$和${\bar ν}_{\rm e}$的反相关偶极发射。然后,我们评估的CCSN喷出物的丰度和质量在后处理的方式。我们发现,不对称的$ν$ -发射导致$p$ -和$n$ -丰富的物质分别在高- $ν_{\rm e}$和- ${\bar ν}_{\rm e}$半球的大量喷射.它大大影响了比镍重的元素的喷出物的丰度,无论祖细胞,虽然这些元素轻于钙是不太敏感。基于这些结果,我们计算了国际货币基金组织的CCSN喷出物的平均丰度考虑到Ia型SNe的贡献。对于$m_{\rm asy} = 10/3\%$和$10\%$,其中$m_{\rm asy}$表示中微子发射中偶极分量的不对称程度,轻于Y的元素的平均丰度与太阳丰度相当,而在$m_{\rm asy} \ge 30\%$的情况下,重于Ge的元素的平均丰度过度产生。我们的结果还表明,不对称中微子发射的影响体现在高- $ν_{\rm e}$半球和高- ${\bar ν}_{\rm e}$半球之间[Ni/Fe]和[Zn/Fe]丰度比的差异上,这表明未来对CCSN遗迹的X射线光谱观测将提供不对称中微子发射的证据。

英文摘要:

We investigate the impact of asymmetric neutrino-emissions on explosive nucleosynthesis in core-collapse supernovae (CCSNe) of progenitors with a mass range of 9.5 to 25$M_{\odot}$. We perform axisymmetric, hydrodynamic simulations of the CCSN explosion with a simplified neutrino-transport, in which anti-correlated dipolar emissions of $ν_{\rm e}$ and ${\bar ν}_{\rm e}$ are imposed. We then evaluate abundances and masses of the CCSN ejecta in a post-processing manner. We find that the asymmetric $ν$-emission leads to the abundant ejection of $p$- and $n$-rich matter in the high-$ν_{\rm e}$ and -${\bar ν}_{\rm e}$ hemispheres, respectively. It substantially affects the abundances of the ejecta for elements heavier than Ni regardless of progenitors, although those elements lighter than Ca are less sensitive. Based on these results, we calculate the IMF-averaged abundances of the CCSN ejecta with taking into account the contribution from Type Ia SNe. For $m_{\rm asy} = 10/3\%$ and $10\%$, where $m_{\rm asy}$ denotes the asymmetric degree of the dipole components in the neutrino emissions, the averaged abundances for elements lighter than Y are comparable to those of the solar abundances, whereas those of elements heavier than Ge are overproduced in the case with $m_{\rm asy} \ge 30\%$. Our result also suggests that the effect of the asymmetric neutrino emissions is imprinted in the difference of abundance ratio of [Ni/Fe] and [Zn/Fe] between the high-$ν_{\rm e}$ and -${\bar ν}_{\rm e}$ hemispheres, indicating that the future spectroscopic X-ray observations of a CCSN remnant will bring evidence of the asymmetric neutrino emissions if exist.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑