A SINGLE DEGENERATE PROGENITOR MODEL FOR TYPE Ia SUPERNOVAE HIGHLY EXCEEDING THE CHANDRASEKHAR MASS LIMIT
A SINGLE DEGENERATE PROGENITOR MODEL FOR TYPE Ia SUPERNOVAE HIGHLY EXCEEDING THE CHANDRASEKHAR MASS LIMIT
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DOI：
10.1088/0004-637x/744/1/69
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发表时间：
2011-06
期刊：
影响因子：
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通讯作者：
I. Hachisu;M. Kato;H. Saio;K. Nomoto
中科院分区：
文献类型：
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作者：
I. Hachisu;M. Kato;H. Saio;K. Nomoto
最近对 Ia 型超新星 (SNe Ia) 的观测表明，一些前身白矮星 (WD) 的质量高达 2.4–2.8 M☉，远远超过了钱德拉塞卡质量极限。我们提出了一种新的 SN Ia 祖细胞的单简并模型，其中 WD 质量可能达到 2.3–2.7 M☉。三个双星演化过程被结合在一起：来自质量吸积WD的光学厚风、WD风从双星伴星的质量剥离以及由差分旋转支持的WD。 WD 质量可以从初始值 1.1 (1.2) M☉ 增加至 2.3 (2.7) M☉，与高光度 SNe Ia 一致，例如 SN 2003fg、SN 2006gz、SN 2007if 和 SN 2009dc。爆炸 WD 存在三个特征质量范围。在极端质量的情况下，由于 T/|W| 处的长期不稳定性，差动旋转 WD 在 WD 质量超过 2.4 M☉ 后不久就会爆炸为 SN Ia。 〜0.14。对于MWD = 1.5–2.4 M☉的中等质量范围，在WD质量达到最大值后，需要一些时间（自旋时间）直到碳被点燃以引发SN Ia爆炸，因为它需要角动量的损失或重新分配。对于刚性旋转 WD 的较低质量情况，MWD = 1.38–1.5 M☉，旋转减速时间取决于 WD 角动量损失的时间尺度。停转时间的差异可能会产生“及时”和“迟缓”组件。我们还认为非常明亮的超钱德拉塞卡质量超新星 Ia 诞生于低金属环境中。
Recent observations of Type Ia supernovae (SNe Ia) suggest that some of the progenitor white dwarfs (WDs) had masses up to 2.4–2.8 M☉, highly exceeding the Chandrasekhar mass limit. We present a new single degenerate model for SN Ia progenitors, in which the WD mass possibly reaches 2.3–2.7 M☉. Three binary evolution processes are incorporated: optically thick winds from mass-accreting WDs, mass stripping from the binary companion star by the WD winds, and WDs being supported by differential rotation. The WD mass can increase by accretion up to 2.3 (2.7) M☉ from the initial value of 1.1 (1.2) M☉, consistent with high-luminosity SNe Ia, such as SN 2003fg, SN 2006gz, SN 2007if, and SN 2009dc. There are three characteristic mass ranges of exploding WDs. In the extreme massive case, differentially rotating WDs explode as an SN Ia soon after the WD mass exceeds 2.4 M☉ because of a secular instability at T/|W| ∼ 0.14. For the mid-mass range of MWD = 1.5–2.4 M☉, it takes some time (spinning-down time) until carbon is ignited to induce an SN Ia explosion after the WD mass has reached maximum, because it needs a loss or redistribution of angular momentum. For the lower mass case of rigidly rotating WDs, MWD = 1.38–1.5 M☉, the spinning-down time depends on the timescale of angular momentum loss from the WD. The difference in the spinning-down time may produce the “prompt” and “tardy” components. We also suggest that the very bright super-Chandrasekhar mass SNe Ia are born in a low-metallicity environment.