• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Astrophysical journal >EG AND: FAR ULTRAVIOLET SPECTROSCOPIC EXPLORER AND HUBBLE SPACE TELESCOPE STIS MONITORING OF AN ECLIPSING SYMBIOTIC BINARY
【24h】

EG AND: FAR ULTRAVIOLET SPECTROSCOPIC EXPLORER AND HUBBLE SPACE TELESCOPE STIS MONITORING OF AN ECLIPSING SYMBIOTIC BINARY

机译：EG AND：远期光谱学探索者和离体共生双星的哈勃空间望远镜监测

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We present highlights and an overview of 20 FUSE and HST STIS observations of the bright symbiotic binary EG And. The main motivation behind this work is to obtain spatially resolved information on an evolved giant star in order to understand the mass-loss processes at work in these objects. The system consists of a low-luminosity white dwarf and a mass-losing, nondusty M2 giant. The ultraviolet observations follow the white dwarf continuum through periodic gradual occultations by the wind and chromosphere of the giant, providing a unique diagnosis of the circum-stellar gas in absorption. Unocculted spectra display high-ionization features, such as the O VI resonance doublet, which is present as a variable (hourly timescales), broad wind profile, which diagnose the hot gas close to the dwarf component. Spectra observed at stages of partial occultation display a host of low-ionization, narrow absorption lines, with transitions observed from lower energy levels up to ～5 eV above ground. This absorption is due to chromospheric/wind material, with most lines due to transitions of Si II, P II, N I, Fe II, and Ni II, as well as heavily damped H I Lyman series features. No molecular features are observed in the wind acceleration region despite the sensitivity of FUSE to H_2. From analysis of the ultraviolet data set, as well as optical data, we find that the dwarf radiation does not dominate the wind acceleration region of the giant and that observed thermal and dynamic wind properties are most likely representative of isolated red giants.
机译：我们提出了亮点和共生二元EG And的20个FUSE和HST STIS观测结果的亮点和概述。这项工作的主要动机是获得关于一颗正在演化的巨星的空间分辨信息，以便了解这些物体在工作中的质量损失过程。该系统由一个低发光度的白矮星和一个质量下降的，尘土飞扬的M2巨人组成。紫外线观测遵循白矮星连续体，通过巨星的风和色球层的周期性渐进掩盖，提供了对吸收中的恒星气体的独特诊断。无隐匿的光谱显示出高电离特征，例如O VI共振双峰，它以变量（每小时时标），宽广的风廓线形式出现，可诊断出接近侏儒成分的热气。在部分掩藏阶段观察到的光谱显示出许多低电离，狭窄的吸收线，并且观察到的跃迁是从较低的能级上升到地面以上约5 eV。这种吸收归因于色层/风物质，大多数谱线归因于Si II，P II，N I，Fe II和Ni II的过渡，以及高度阻尼的H I Lyman系列特征。尽管FUSE对H_2敏感，但在风加速区域未观察到分子特征。通过对紫外线数据集和光学数据的分析，我们发现矮辐射并没有支配巨星的风加速区域，并且观察到的热和动态风属性最有可能代表孤立的红色巨星。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号