CQ Aurigae / CQ Aur
Light curves and phase diagrams of the EA type eclipsing binary CQ Aurigae/ CQ Aur.
The following light curve and phase diagram were constructed from photometry of 101 images taken with a V filter with the Open University COAST telescope (a 14 inch Schmidt- Cassegrain) between 2017 August 3 and 2018 January 25.
A further 22 images taken through a tri-colour green filter with the Bradford Robotic Telescope Cluster Camera (BRT) (a 64mm f3 telephoto lens) between 2014 October 23 and 2016 January 1 were reduced to generate the following light curve and phase diagram.
The above two sets of results were taken with different systems through different filters, but the results are combined in the following light curve and phase diagram just out of interest.
The COAST phase diagram is asymmetrical and 'noisy', the maximum between secondary and the primary minima showing more scatter than that between the primary and the secondary minima. The system is catalogued as an EA/RS type, which have a light curve which can have unequal maxima and can also change over many cycles (the O'Connell effect, possibly due to 'starspots'). This might be responsible for the quasi-sinusoidal variation in the maxima seen in the COAST light curve. More observations needed.
The period is catalogued as 10.621943d (AAVSO VSX), 10.6226d (Kreiner) and 10.62251d (GCVS http://www.as.up.krakow.pl/minicalc/AURCQ.HTM) (accessed 2018 February 22).
The 'best fit' period to my data is 10.622477d for the combined data and 10.624734d for the COAST data alone. The above phase diagrams were all plotted to 10.6219d for consistency.
The period is catalogued as 10.621943d (AAVSO VSX), 10.6226d (Kreiner) and 10.62251d (GCVS http://www.as.up.krakow.pl/minicalc/AURCQ.HTM) (accessed 2018 February 22).
The 'best fit' period to my data is 10.622477d for the combined data and 10.624734d for the COAST data alone. The above phase diagrams were all plotted to 10.6219d for consistency.
[Page updated 2018 February 22]