PN fast winds: temporal structure and stellar rotation Structure in PN fast winds
PN fast winds: temporal structure and stellar rotation Structure in PN fast winds
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PN 快风：时间结构和恒星自转 PN 快风中的结构
DOI：
10.1111/j.1365-2966.2012.20838.x
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发表时间：
2012
影响因子：
4.8
通讯作者：
Prinja R
中科院分区：
文献类型：
--
作者：
Prinja R
为了诊断行星状星云中心星(CSPNe)快速风中的时变结构，我们分析了P-Cygni谱线在红外光谱探测器卫星远紫外(FUV)光谱数据中的分布。检索档案谱以形成富H CSPN NGC6826、IC418、IC2149、IC4593和NGC6543的时间序列数据集。尽管由于时间序列的零散采样而受到限制，但我们证明，在所有五个CSPN中，UV共振线是可变的，主要是由于蓝向迁移的离散吸收分量(DAC)的出现。经验(索博列夫精确积分)线合成模式被用来确定径向光学厚度的波动范围，这些波动被分配给大尺度风结构的时间变化。我们认为，DAC在CSPN风中很常见，它们的经验性质类似于大质量OB星的吸收槽中看到的类似结构。通过对目标恒星光球线的快速傅里叶变换分析，得到了对Pn中心星自转速度的约束。考虑到自转相互作用区的因果作用，我们探索了归一化DAC加速度与Pn中心星和O星的自转速率之间的关系。这些比较性质表明，在两种不同的环境中，同样的物理机制在线驱动风中产生了大尺度结构。
To diagnose the time-variable structure in the fast winds of the central stars of planetary nebulae (CSPNe), we present an analysis of P Cygni line profiles inFar Ultraviolet Spectroscopic Explorersatellite far-ultraviolet (FUV) spectroscopic data. Archival spectra are retrieved to form time-series data sets for the H-rich CSPN NGC 6826, IC 418, IC 2149, IC 4593 and NGC 6543. Despite limitations due to the fragmented sampling of the time series, we demonstrate that in all five CSPN the UV resonance lines are variable primarily due to the occurrence of blueward migrating discrete absorption components (DACs). Empirical (Sobolev with Exact Integration) line-synthesis modelling is used to determine the range of fluctuations in radial optical depth, which are assigned to the temporal changes in large-scale wind structures. We argue that DACs are common in CSPN winds, and their empirical properties are akin to those of similar structures seen in the absorption troughs of massive OB stars. Constraints on PN central star rotation velocities are derived from the fast Fourier transform analysis of photospheric lines for our target stars. Favouring the causal role of corotating interaction regions, we explore connections between normalized DAC accelerations and rotation rates of PN central stars and O stars. The comparative properties suggest that the same physical mechanism is acting to generate large-scale structure in the line-driven winds in the two different settings.