Modeling the Evolutionary Paths to Type Ia Supernovae

Ia 型超新星的演化路径建模

基本信息

批准号：
11640226
负责人：
HACHISU Izumi
金额：
$ 1.86万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640226/
关键词：
Type Ia supernovae binaries stellar winds supernova explosions supersoft X-ray sources mass-accretion

项目摘要

We have proposed tow evolutionary paths to Type la supernovae (Sne Ia) based on our optically thick wind model of mass accreting white dwarfs. In the first year of my research (1999), we have found that white dwarfs begin to blow strong winds and when the mass accretion rate exceeds the critical rate, thus preventing the binary from collapsing. The binary does not spiral-in but keeps its separation. We call this accretion wind evolution instead of common envelope evolution.Based on the new mechanism of accretion wind evolution, we have found two paths to Sne Ia (Hachisu et al. 1999). In these two paths, white dwarfs can accrete mass continuously from the companion and grow at a rate of about one millionth of solar masses per year. Therefore, candidates for SN la progenitors are systems at the final stages on these paths ; i.e., one is a supersoft X-ray source (SSS) consisting of a white dwarf and a lobe-filling, more massive, main-sequence star and the other is a symbiotic star consist … More ing of a white dwarf and a mass-losing red giant. Both the systems contribute to main parts of the SN la birth rate.In the second year of my research, we have showed that the borders of such two regions of the WD+MS systems (SSS channel) and the WD+RG systems (symbiotic channel) correspond to the recurrent novae. These recurrent novae lie on the boarder of their parameter region that can produce an SN Ia. Foi example, we have estimated, from the light curve fitting, that the white dwarf mass of U Sco, one of the recurrent nova, is as large as 1.37 solar masses, just before the SN Ia explosion.In the third year of my research, we have also estimated the while dwaif masses for other recurrent novae, for example, symbiotic type recurrent novae, RS Oph, T CrB, and so on. The estimated masses are also very close to the Chandrasekhar mass limit. It is concluded that the member of the recurrent nova class are an immediate progenitor of Type la supernovae.In the final year of my research, we have theoretically identified the system just in the accretion wind evolution. The supersoft X-ray source in the Large Magellanic Clouds (LMC), RX J0513.9-6951, shows a prominent transition between optical high and optical low stales. Soft X-rays were observed only in the optical low stale. We have modeled the on/off of soft X-rays as well as the optical high/low states based on our optically thick wind mass loss model of mass-accreting while dwarfs. We have already predicted such systems in the accretion wind evolutions. This strongly supports our evokutionary model to Type Ia supernovae. Less

我们提出了基于我们的光学厚风模型的质量较厚的白矮人风模型。在我的研究的第一年（1999年）中，我们发现白矮人开始吹强风，当质量积聚率超过关键率时，从而阻止了二元崩溃。二进制不会螺旋插入，而是保持其分离。我们称这种增强风的演化，而不是共同的包膜演化。基于新的吸积风演化机制，我们找到了两条通往SNE IA的途径（Hachisu等，1999）。在这两条路径中，白矮人可以从同伴中连续积聚质量，并以每年大约一百万太阳能质量的速度增长。因此，SN LA祖细胞的候选者是在这些路径上的最后阶段的系统。即，一个是由白色矮人和叶片填充，更庞大的，更大的主序列恒星组成的超级X射线源（SSS），另一个是共生之星……更多的是白色矮人和大量失去的红色巨人。这两个系统都促进了SN LA出生率的主要部分。在我研究的第二年，我们表明WD+MS系统（SSS渠道）和WD+RG Systems（共生通道）的两个区域的边界对应于复发性Novae。这些复发性的诺瓦在其参数区域的寄宿生中，可以产生SN IA。从光曲线拟合中，我们已经估计，在我研究的第三年，我们还估计，我们还估计了其他复发型Novae，例如，symbiot of nokh of nokh yociot of noveh of nove，我们还估计了其他复发性的symbiot of novh nokh ynov，我们还估计了其他复发性novae symbiot of nokh yokh，foi估计的是u sco的白色矮人质量，u sco的质量为1.37个太阳能大量。在我研究的第三年。到Chandrasekhar质量限制。结论是，经常性新星类的成员是La Supernovae型的直接祖先。在我的研究的最后一年中，我们理论上已经在积聚风中确定了该系统。大型麦哲伦云（LMC），RX J0513.9-6951中的Supersoft X射线源显示出光学高和光学低块之间的突出过渡。仅在光学低陈旧中观察到软X射线。我们已经根据我们的光学厚度质量损失模型在矮人的同时建模了软X射线的ON/ON/OFF，以及光学高/低状态。我们已经预测了积聚风力的这种系统。这强烈支持我们的进化模型，以替代IA型超新星。较少的