Theoretical Modeling of the Thermal State of Accreting White Dwarfs Undergoing Classical Nova Cycles
Theoretical Modeling of the Thermal State of Accreting White Dwarfs Undergoing Classical Nova Cycles
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DOI：
10.1086/379647
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
D. Townsley;L. Bildsten
中科院分区：
文献类型：
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作者：
D. Townsley;L. Bildsten
当白色矮星（WD）从双星中的伴星接收质量时，它们会经历一次热复兴。对于小于10 - 8 M/yr-1的吸积速率，新积累的氢/氦包层以热不稳定的方式点燃，导致经典新星（CN）爆发和物质喷射。我们已经进行了理论研究的积累信封上的热状态的基础WD的影响。这使我们能够找到平衡WD核心温度（Tc），CN点火质量（米格），和WD吸积的热光度在10 - 11至10 - 8兆年-1的速率。这些吸积率是最合适的WD激变变量（CV）的Porb 107小时，其中许多吸积零星的矮新星。我们已经包括3He在适当的CV水平的吸积材料，并发现它显着修改CN点火质量。我们比较我们的结果与其他几个从CN文献，并发现，列入3He导致较低的价值观的Mign为10 - 10兆年-1，并为低于此特定作者的假设Tc，我们计算一致，是一个决定性的因素。我们的CN点火质量与实测喷射质量的初步比较发现合理的协议，并指出喷射的材料相媲美的吸积。
White dwarfs (WDs) experience a thermal renaissance when they receive mass from a stellar companion in a binary. For accretion rates of less than 10-8 M☉ yr-1, the freshly accumulated hydrogen/helium envelope ignites in a thermally unstable manner that results in a classical nova (CN) outburst and ejection of material. We have undertaken a theoretical study of the impact of the accumulating envelope on the thermal state of the underlying WD. This has allowed us to find the equilibrium WD core temperatures (Tc), the CN ignition masses (Mign), and the thermal luminosities for WDs accreting at rates of 10-11 to 10-8 M☉ yr-1. These accretion rates are most appropriate for WDs in cataclysmic variables (CVs) of Porb ≲ 7 hr, many of which accrete sporadically as dwarf novae. We have included 3He in the accreted material at levels appropriate for CVs and find that it significantly modifies the CN ignition mass. We compare our results with several others from the CN literature and find that the inclusion of 3He leads to lower values of Mign for ⟨⟩ ≳ 10-10 M☉ yr-1 and that for ⟨⟩ values below this the particular author's assumption concerning Tc, which we calculate consistently, is a determining factor. Initial comparisons of our CN ignition masses with measured ejected masses find reasonable agreement and point to ejection of material comparable to that accreted.