Free Access

Fig. 2

thumbnail

Measured passband (grey dashed line) of the Lyot filter used for ChroTel Ca ii K observations. The zero point marks the minimum of the Ca ii K line at 3933.7 Å. For comparison, a spectrum around the Ca ii K line is overplotted (solid line, recorded with the spectrograph of the VTT).

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.