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arXiv 1606.08149astro-ph.SR
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无法用双星系统解释的行星状星云

Planetary nebulae that cannot be explained by binary systems

Ealeal Bear, Noam Soker

摘要:

我们研究了数百个行星状星云(PNe)的图像,发现大约有六分之一的PNe的形态太“凌乱”,不能用恒星双星相互作用的模型来解释。我们推测,相互作用的三重恒星系统塑造了这些PNE。在这个初步的研究中,我们定性分类PNe的四个类别之一。(1)PNE表明不需要第三恒星来解释它们的形态。(2)其结构具有明显偏离轴对称和/或镜像对称的PNe。根据我们的推测,我们将其归类为“具有三颗恒星的祖先”。(3)其形态偏离轴对称和/或镜像对称,但不像前一类那样明显,并被归类为“可能由三重恒星系统形成”。(4)与轴对称和/或镜像对称有微小偏离的PNe,也可能是由偏心双星系统或星际介质引起的。它们被归类为“可能由三重恒星系统形成”。在第2、3、4类星体的权重分别为eta_t=1、eta_l=0.67、eta_m=0.33的情况下,我们发现,根据我们的假设,大约13 - 21%的PNe是由三星系统塑造的。虽然在某些演化场景中,并非所有的三颗恒星都能在演化过程中幸存下来,但我们鼓励在一些PNE的中心寻找三颗恒星系统。

英文摘要:

We examine the images of hundreds of planetary nebulae (PNe) and find that for about one in six PNe the morphology is too `messy' to be accounted for by models of stellar binary interaction. We speculate that interacting triple stellar systems shaped these PNe. In this preliminary study we qualitatively classify PNe by one of four categories. (1) PNe that show no need for a tertiary star to account for their morphology. (2) PNe whose structure possesses a pronounced departure from axial-symmetry and/or mirror-symmetry. We classify these, according to our speculation, as `having a triple stellar progenitor'. (3) PNe whose morphology possesses departure from axial-symmetry and/or mirror-symmetry, but not as pronounced as in the previous class, and are classified as `likely shaped by triple stellar system'. (4) PNe with minor departure from axial-symmetry and/or mirror symmetry that could have been as well caused by an eccentric binary system or the inter-stellar medium. These are classified as `maybe shaped by a triple stellar system'. Given a weight eta_t=1, eta_l=0.67, eta_m=0.33 to classes 2, 3 and 4, respectively, we find that according to our assumption about 13 - 21% of PNe have been shaped by triple stellar systems. Although in some evolutionary scenarios not all three stars survive the evolution, we encourage the search for a triple stellar systems at the center of some PNe.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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