摘要
计算了总质量为3.9M,具有不同初始质比和两子星间距的一组模型在总质量、总角动量守恒假设下的Case A演化,以探求Case A演化与几乎相接双星(NCS)可能的联系.结果表明确实存在经过Case A质量交流演化为NCS系统的途径。并且这样形成的NCS系统其随后的演化有两种前景:一种随即演化为相接系统;另一种则经由慢速质量交流成为较稳定的半接或不接系统.但能够演化为NCS状态的初始模型范围极为狭窄,本文大致确定了它们的初始质比、子星间距等参量范围. 结合模型计算结果,对已知29个NCS系统作了统计研究,结果表明NCS系统与相接双星在演化上有很密切的联系.
The computation of case A evolution was carried out for a low mass binary system of 3.9 solar masses. A total of 15 models with different initial mass ratios and separations were calculated under conversation assumption. It was revealed that the NCS system can be formed by Case A mass transfer without contact phase ,but the range of the initial models is limited. Compared with the computations, a statistical study of 29 known NCS systems was made. Two future evolution traces were shown for NCS systems: one will evolve into contact; and the other will get in detached and or semi-detached state.
