Free Access

Fig. 3


Periodogram analysis of the variability amplitudes mi of AO 0235+164. Four peaks of power are clearly visible; three of them correspond to periods of 1, 1/2, and 1/3 of year (red arrows), i.e., the first three harmonics of a one-year periodic signal. This is strong evidence in favour of an annual cycle in the variability amplitude of the source.

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.