THE IMPACT OF TYPE Ia SUPERNOVA EXPLOSIONS ON HELIUM COMPANIONS IN THE CHANDRASEKHAR-MASS EXPLOSION SCENARIO
THE IMPACT OF TYPE Ia SUPERNOVA EXPLOSIONS ON HELIUM COMPANIONS IN THE CHANDRASEKHAR-MASS EXPLOSION SCENARIO
复制标题
钱德拉塞卡质量爆炸场景中 Ia 型超新星爆炸对氦伴星的影响
DOI：
10.1088/0004-637x/774/1/37
复制
发表时间：
2013-09-01
影响因子：
4.9
通讯作者：
Han, Z. W.
中科院分区：
文献类型：
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作者：
Liu, Zheng-Wei;Pakmor, R.;Han, Z. W.
在这里研究的Ia型超新星（SNe Ia）的单简并情景中，一颗碳氧白矮星在吸积了一颗非简并氦（He）伴星的物质后，在接近钱德拉塞卡极限时爆炸。在本研究中，我们使用恒星GADGET代码对SN Ia抛射物与He伴星的相互作用进行了三维流体动力学模拟，并考虑了其轨道运动和自旋。研究发现，由于超新星（SN）的撞击，He伴星的外层只有2%-5%的初始伴星质量被剥离。对于给定的伴生模型，非束缚质量（或弹射速度）对轨道分离的依赖关系可以用幂定律很好地拟合。SN撞击后，氦供体恒星的外层显著富集了来自SN Ia喷射物低膨胀速度尾部的重元素。在不同的伴星模型中，伴星表面积累的sn抛射物质的总质量约大于或接近10(-3)M（圆点）。这种重元素的富集提供了一种从观测上识别SN残骸中幸存的伴星的潜在方法。最后，通过人为调整W7爆炸模型的爆炸能量，我们发现SN抛射物在伴星表面的总积累也依赖于爆炸能量，并且呈幂律关系，具有很好的近似。
In the version of the single-degenerate scenario of Type Ia supernovae (SNe Ia) studied here, a carbon-oxygen white dwarf explodes close to the Chandrasekhar limit after accreting material from a non-degenerate helium (He) companion star. In the present study, we employ the STELLAR GADGET code to perform three-dimensional hydrodynamical simulations of the interaction of the SN Ia ejecta with the He companion star taking into account its orbital motion and spin. It is found that only 2%-5% of the initial companion mass is stripped off from the outer layers of He companion stars due to the supernova (SN) impact. The dependence of the unbound mass (or the kick velocity) on the orbital separation can be fitted to a good approximation by a power law for a given companion model. After the SN impact, the outer layers of a He donor star are significantly enriched with heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total mass of accumulated SN-ejecta material on the companion surface reaches about greater than or similar to 10(-3)M(circle dot) for different companion models. This enrichment with heavy elements provides a potential way to observationally identify the surviving companion star in SN remnants. Finally, by artificially adjusting the explosion energy of the W7 explosion model, we find that the total accumulation of SN ejecta on the companion surface is also dependent on the explosion energy with a power-law relation to a good approximation.