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Type EA, difficulty finding secondary minimum

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Type EA, difficulty finding secondary minimum

The attached light curves show a type EA variable. The best period I could find was 2.209422. Each SuperWASP plot contains 1000 data points, and the ROTSE3 plot contains 131 data points. There is a possible secondary minimum in the SuperWASP data, but it is not centered and could just be noise. In Gaia DR2, there are two stars, one of Gmag 13.538 and one of 16.271 separated by 13". The 16.271 Gmag might be the compainion to the 13.538 Gmag, and if so this difference in magnitude could account for the lack of a secondary. Do you have any suggestions for improving the period? Could the small dips in the SuperWASP data be the secondary, or just noise? Is the difference in magnitude between the two stars great enough that a secondary might not be visible?

If you're trying to fit for a

If you're trying to fit for a primary eclipse and there are many datapoints that are shifted to the left (or right, but one side), means you have to double your period. Possibly it's an eccentric binary, so you have to check for that. Your secondary eclipse could be at phase ~0.48 or ~0.52.


Gabriel Murawski

Here is it phased with twice

Here is it phased with twice the period.

Possible secondary is most likely noise

I re-phased with only WASP data that was taken close together, and the possible secondary disappeared, suggesting this was indeed just noise.

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