Fig. 6
Download original image
Ratio images of NGC 4361 in He lines (top): He II 5412 Å/Hβ (left) and He I 5876 Å/He II 5412 Å (right) demonstrating that a very large fraction of He is fully ionised throughout the nebula. Ratio images displaying the ionisation zones (bottom): [O III] 5007 Å/Hβ (left) for the medium ionisation zone and [Ar V] 7006 Å/Hβ for the highest ionisation (right).
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.