论文标题
揭示Vela-星际线在Vela Supernova Remnant III方向上的变异性。 Na D和Ca II K
Unveiling Vela -- Variability of Interstellar Lines in the Direction of the Vela Supernova Remnant III. Na D and Ca II K
论文作者
论文摘要
2017 - 2019年获得了高分辨率光谱，南非大型望远镜的15颗恒星沿Vela Supernova残留物的方向获得。本文讨论了星际CA II H和K和Na I D线。特别地，将线曲线与Cha＆Sembach在1993 - 1996年获得的可比光谱分辨率下进行了比较。视线中的十种显示了该视线中一个或多个组件的变化。变化包括径向速度的微小变化（1-2 km/s）和/或在观察周期之间的二十年中等效宽度的增加/减小。在CA K线中，变化比在NA D线中更明显。这些变化归因于超新星喷射和周围星际介质之间相互作用的气体。代表性的时间表可能是20 - 50年。如前所述，在残留物面上的小规模变化表明，相互作用的线性尺度是当前残留物的40 pc大小的一小部分。
High-resolution optical spectra were obtained in 2017-2019 with The Southern African Large Telescope of fifteen stars in the direction of the Vela supernova remnant. Interstellar Ca ii H and K and Na i D lines are discussed in this paper. In particular, the line profiles are compared with profiles at a comparable spectral resolution obtained in 1993-1996 by Cha & Sembach. Ten of the lines of sight show changes to one or more of the components in that line of sight. Changes include small changes (1-2 km/s) in radial velocity and/or increases/decreases in equivalent width over the two decades between the periods of observation. Changes are more obvious in the Ca K line than in the Na D lines. These changes are attributed to gas disturbed by interactions between the supernova ejecta and the surrounding interstellar medium. A representative timescale may be 20-50 years. Small-scale variations in line profiles across the face of the remnant suggest, as previously remarked, that a linear scale for interactions is a small fraction of the 40 pc size of the present remnant.
