论文标题
类似氦气的X射线线综合体表明，O Supergiant Zeta Puppis上最热的等离子体在风中
Helium-like X-ray line complexes show that the hottest plasma on the O supergiant zeta Puppis is in its wind
论文作者
论文摘要
我们介绍了类似氦气的关键系列复合物的Chandra光栅光谱的分析，以在位置对最热的光球（$ t \ gtrsim {6 \ times 10^6} $ k）等离子体的光，在O Supergiant Zeta Pup的风中，并探索了这两个观察者之间的18年变化。我们适合两种模型 - 一种经验和一种基于风力的模型 - 与S XV，Si XIII和MG XI线复合体相适应，并表明风流中的原点高于$ r \ r \ r \ r $ $ _ {\ ast} $，比起0.3 r $ _ {\ ast $ 1. $ 1. r $ _ {\ ast} $），尤其是在最新的，非常长的曝光数据集中。自从第一个Chandra Grating观察Zeta Pup观察到的18年中，线和连续通量，线宽度，风吸收特征以及热等离子体与Photosphere的距离有所增加。两种建模模式都包括介电重组卫星发射线混合对氦样复合物的影响 - 在O恒星中HE样线比的分析中，这是第一次考虑到这一点。
We present an analysis of Chandra grating spectra of key helium-like line complexes to put constraints on the location with respect to the photosphere of the hottest ($T \gtrsim{6 \times 10^6}$ K) plasma in the wind of the O supergiant zeta Pup and to explore changes in the 18 years between two sets of observations of this star. We fit two models -- one empirical and one wind-shock-based -- to the S XV, Si XIII, and Mg XI line complexes and show that an origin in the wind flow, above $r \approx 1.5$ R$_{\ast}$, is strongly favored over an origin less than 0.3 R$_{\ast}$ above the photosphere ($r \lesssim 1.3$ R$_{\ast}$), especially in the more recent, very long-exposure data set. There is a modest increase in the line and continuum fluxes, line widths, wind absorption signatures, and of the hot plasma's distance from the photosphere in the 18 years since the first Chandra grating observation of zeta Pup. Both modes of modeling include the effects of dielectronic recombination satellite emission line blending on the helium-like complexes -- the first time this has been accounted for in the analysis of He-like line ratios in O stars.
