Image Details
Caption: Figure 13.
Keck/NIRSPEC line profiles for LkHα 225 South in He I 10830 Å, H I Paγ, and Sr II. The magenta spectrum is from 2019 June while the green spectrum is from September 2020. In the He I panel, the marked Si I line at 10827 Å is unlikely to be a contributor to the observed profile, given the absence of comparable-strength Si I lines at 10844 and 10870 Å. Similarly, in the Sr II panel, the marked Mg II line at 10914 Å is unlikely to be a contributor to the observed profile, given the absence of a comparable-strength line at 10952 Å. The narrow absorption features in the Paγ and Sr II panels are uncorrected telluric lines. While the He I profile shows no change, the H I line has evolved from a P Cygni profile to pure absorption. The Sr II profile has evolved similarly. These line profiles can be compared to those exhibited by the cooler optical wind lines of Figure 11.
© 2022. The Author(s). Published by the American Astronomical Society.