Fig. 2.
Stacked spectrum (filled gray histogram) of several nα RRLs (n = 54–59). The spectrum is centered at the frequencies of Snα lines and shows the expected position of Mg, Si, and Fe nα RRLs. The black curve is a three-Gaussian line fit: Snα (blue), Cnα (red), and Henα (green). Vertical dashed lines mark the LSR velocity of the Bar PDR.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.