论文标题
在热他富含白色矮人高清149499b的大气中检测剖腹
Detection of cesium in the atmosphere of the hot He-rich white dwarf HD 149499B
论文作者
论文摘要
我们报告了白矮人大气中首次检测到剖宫产（Z = 55）。 CS IV，CS V和CS VI的十几个吸收系已在HE-RICH白色矮人HD 149499B的远紫外光谱探索器光谱中鉴定出来（Teff = 49,500 K，Log G = 7.97）。这些线的等效宽度范围为2.3至26.9mÅ。我们进行了光谱合成分析，以确定大气中的铯含量。通过在计算中明确考虑剖宫产来计算非LTE大气模型。为此，我们计算了CS IV-CS VI的界限过渡的振荡器强度，这些振荡均具有自动结构（多构型BREIT-PAULI）和GRASP2K（MulticonFiguration Dirac-fock）原子结构代码，既不是测量值，也没有曾经曾经有过理论值。我们确定了log n（cs）/n（He）= -5.45（0.35）的仪式丰度，这也可以用质量分数log x（cs）= -3.95（0.35）表示。
We report the first detection of cesium (Z = 55) in the atmosphere of a white dwarf. Around a dozen absorption lines of Cs IV, Cs V, and Cs VI have been identified in the Far Ultraviolet Spectroscopic Explorer spectrum of the He-rich white dwarf HD 149499B (Teff = 49,500 K, log g = 7.97). The lines have equivalent widths ranging from 2.3 to 26.9 mÅ. We performed a spectral synthesis analysis to determine the cesium content in the atmosphere. Non-LTE atmosphere models were computed by considering cesium explicitly in the calculations. For this purpose we calculated oscillator strengths for the bound-bound transitions of Cs IV-Cs VI with both AUTOSTRUCTURE (multiconfiguration Breit-Pauli) and GRASP2K (multiconfiguration Dirac-Fock) atomic structure codes as neither measured nor theoretical values are reported in the literature. We determined a cesium abundance of log N(Cs)/N(He) = -5.45(0.35), which can also be expressed in terms of the mass fraction log X(Cs) = -3.95(0.35).
