Scatter plots of the actual (left panels) and mid-point-inferred (right panels) first-skip turning points for the grid of rays fired from (−60, 0) Mm with frequency 4 mHz (top) and 3 mHz (bottom). Points (actually) in the umbra are identified with green colouring, the penumbra with red, and the quiet Sun with blue. The green and red circles are the umbral and penumbral boundaries, respectively. These figures use ωc = ωDG; scattering with ωc = ωI is typically substantially increased.
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.