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arXiv 1406.4408astro-ph.SR
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行星状星云Kn 61和Pa 5的分光光度研究

A spectroscopic and photometric study of the planetary nebulae Kn 61 and Pa 5

Ma. T. García-Díaz, D. González-Buitrago, J. A. López, S. Zharikov, G. Tovmassian, N. Borisov, G. Valyavin

摘要:

本文首次对行星状星云Kn 61和Pa 5进行了形态运动学分析,并探讨了它们中心恒星的性质。我们的分析是基于高分辨率和中等分辨率的光谱观测,深窄带成像,和积分测光。这种材料使我们能够识别形态组件并研究其运动学。直接图像和光谱表明,在这两个星云中没有特征的[N II]和[S II]发射线。Kn 61的星云光谱显示它是一个缺氢的行星状星云,而中央恒星的恒星光谱则显示它是一颗缺氢的PG 1159型恒星。[O III]位置速度图显示,Kn 61是一个封闭的、空的、球形壳,有一个薄的边界和一个以67.6 km s $^{-1}$膨胀的粘性表面,并且壳目前不是各向同性膨胀的。在距离为4千秒差距的假设下,我们推导出了$\sim$ 1.6 $\times$ 10 $^4$ yrs的运动学年龄。Kn 61的光度周期为$\sim$ 5.7($\pm$ 0.4)天,表明在其核心可能存在一个双星系统。一个可能的联系,球状壳和PG 1159型恒星之间的注意。Pa 5的形态主要是赤道环和微弱的极区延伸。这个行星状星云的赤道区域正在以45.2公里的速度扩张$^{-1}$。恒星光谱对应于一个非常热的恒星,主要是一个陡峭的蓝色上升连续和He II,Balmer和Ca II光球线。

英文摘要:

We present the first morpho-kinematical analysis of the planetary nebulae Kn 61 and Pa 5 and explore the nature of their central stars. Our analysis is based on high resolution and medium resolution spectroscopic observations, deep narrow-band imaging, and integral photometry. This material allows us to identify the morphological components and study their kinematics. The direct images and spectra indicate an absence of the characteristic [N II] and [S II] emission lines in both nebulae. The nebular spectrum of Kn 61 suggests an hydrogen deficient planetary nebula and the stellar spectrum of the central star reveals a hydrogen deficient PG 1159-type star. The [O III] position velocity diagram reveals that Kn 61 is a closed, empty, spherical shell with a thin border and a filamentary surface expanding at 67.6 km s$^{-1}$, and the shell is currently not expanding isotropically. We derived a kinematic age of $\sim$ 1.6$\times$10$^4$ yrs for an assumed distance of 4 kpc. A photometric period of $\sim$ 5.7($\pm$0.4) days has been detected for Kn 61, indicating presence of a possible binary system at its core. A possible link between filamentary, spherical shells and PG 1159-type stars is noted. The morphology of Pa 5 is dominated by an equatorial toroid and faint polar extensions. The equatorial region of this planetary nebula is expanding at 45.2 kms$^{-1}$. The stellar spectrum corresponds to a very hot star and is dominated by a steep blue rising continuum and He II, Balmer and Ca II photospheric lines.

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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