发表机构
INAF-Osservatorio Astronomico d’Abruzzo; INFN - Sezione di Perugia; Institute of Astronomy of the Russian Academy of Sciences; Departamento de Física Teórica y del Cosmos, Universidad de Granada（阿布鲁佐天文台; 佩鲁贾意大利国家核物理研究所; 俄罗斯科学院天文学研究所; 格拉纳达大学理论与宇宙物理学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究双星CD - 30°11223是否会爆发超新星，用恒星演化代码FuNS并考虑磁不稳定性导致的角动量传输来计算其演化，发现该系统不能成为Ia型超新星的潜在前身，此结论适用于类似的分离双星系统。
AI 中文摘要
背景：在一个拥有富氦供体的双星系统中，富氦物质吸积到低质量碳氧白矮星上可能引发Ia型超新星爆发事件，尽管峰值光度较低且核合成特殊。近期这一说法受到质疑，认为考虑吸积体演化中的旋转效应后，它不会爆发，而是成为一个带有大量氦缓冲层的白矮星。目的：我们研究当前分离的双星CD - 30°11223的预期演化，其包含一颗0.74太阳质量的碳氧白矮星和一颗0.47太阳质量的供体，供体有一个氦燃烧核心和非常薄的氢包层（ΔM_H = 6e - 4太阳质量）。方法：我们使用恒星演化代码FuNS计算CD - 30°11223的演化。相较于我们早期对系统PTF J2238 + 743015.1的研究，我们还包括了由于吸积体内磁不稳定性导致的角动量传输（“磁模型”）。结果：在氢吸积阶段，吸积体中旋转的影响可忽略不计。在“磁模型”中，由于磁不稳定性，吸积物质沉积的角动量能非常有效地沿整个白矮星重新分布，使得吸积层的角速度保持很低。在氦吸积阶段，吸积体经历两次非常强烈的氦闪，导致之前吸积的大部分物质从双星系统中被抛出。该系统以一个由大量氦/碳/氧包层（ΔM_env ~ 0.194太阳质量）覆盖的碳氧核心和一个极低质量的伴星（供体的残余）结束其生命。结论：系统CD - 30°11223不能被视为Ia型超新星的潜在前身。这一结论也适用于所有具有相似组件质量和轨道周期的分离双星系统。
英文摘要
Accretion of He-rich matter onto a low-mass CO WD from a He-rich donor may lead to an explosive event of SN Ia proportion, though with low peak luminosity and peculiar nucleosynthesis. Recently such a possibility for some binaries with He-accreting WDs has been questioned, suggesting that, if the effects of rotation are accounted for in the evolution of the accretor, the latter does not explode, but it becomes a WD with a massive He-buffer. We investigate the expected evolution of the currently detached binary CD-3011223 harboring a 0.74Msun CO WD and a 0.47Msun donor with a He-burning core and a very thin H-envelope. We use the stellar evolution code FuNS to compute the evolution of CD-3011223 up to the epoch when the two components come into contact and through the RLOF phase of the donor. With respect to our earlier study of the system PTF J2238+743015.1, we also include the transport of angular momentum due to magnetic instabilities (magnetic model). During the H-accretion phase, the effects of rotation in the accretor are negligible. In the "magnetic model", the angular momentum deposited by the accreted matter is very efficiently redistributed along the whole WD due to magnetic instabilities, so that the angular velocity of the accreted layers remains very low. During the He-accretion phase, the accretor experiences two very strong He-flashes, which result in the ejection from the binary system of a large part of the matter previously accreted. The system ends its life as a CO core capped by a massive He/C/O-envelope (Delta M_env ~ 0.194Msun) and an extremely low-mass companion, remnant of the donor, like in a rotating model not including the effects of magnetic field. The system CD-3011223 cannot be regarded as the potential progenitor of Supernova Ia. Such a conclusion applies also to all detached binary systems having similar masses of components and orbital periods.
Comments10 pages, 8 figures, Accepted for the publication in Astronomy & Astrophysics
