Fig. 31
Histogram (blue) of the distribution of photon indices between 1 and 7 for sources with at least 100 source counts, at least four degrees of freedom and reduced χ2 values lower than 1.5. The red dashed line gives the integral distribution.
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.