论文标题
O Supergiant $ζ$幼犬的Chandra光谱测量表明，在18年内风质量损失率令人惊讶
Chandra spectral measurements of the O supergiant $ζ$ Puppis indicate a surprising increase in the wind mass-loss rate over 18 years
论文作者
论文摘要
自Chandra第一个观察到的周期以来的18年中，新的Long Chandra Grating观察结果不仅显示了X射线排放线通量的增强，还显示出13％的增光幅度为13％。我们通过对配置文件和高斯配件的非参数分析来证明这一点，然后使用线条型模型拟合来得出$ 2.47 \ pm 0.09 \ pm 0.09 \ times 10^{ - 6} $ msun/yr的质量损失率，这比从周期1数据中获得的值增加了40％。短波长线的单个发射线通量的增加比长波长线更大，这是预期的，如果线发射均匀增加，伴随着嵌入了冲击热等离子体的冷风依赖波长依赖性吸收。
New long Chandra grating observations of the O supergiant $ζ$ Pup show not only a brightening of the x-ray emission line flux of 13 per cent in the 18 years since Chandra's first observing cycle, but also clear evidence - at more than four sigma significance - of increased wind absorption signatures in its Doppler-broadened x-ray emission line profiles. We demonstrate this with non-parametric analysis of the profiles as well as Gaussian fitting and then use the line-profile model fitting to derive a mass-loss rate of $2.47 \pm 0.09 \times 10^{-6}$ Msun/yr, which is a 40 per cent increase over the value obtained from the cycle 1 data. The increase in the individual emission line fluxes is greater for short-wavelength lines than long-wavelength lines, as would be expected if a uniform increase in line emission is accompanied by an increase in the wavelength-dependent absorption by the cold wind in which the shock-heated plasma is embedded.
