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arXiv · 1805.02452

On the Colour Variations of Negative Superhumps

Akira Imada·Kenshi Yanagisawa·Nobuyuki Kawai
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Abstract

We present simultaneous $g'$, $R_{\rm c}$, and $I_{\rm c}$ photometry of the notable dwarf nova ER UMa during the 2011 season. Our photometry revealed that the brightness maxima of negative superhumps coincide with the bluest peaks in $g' - I_{\rm c}$ colour variations. We also found that the amplitudes of negative superhumps are the largest in the $g'$ band. These observed properties are significantly different from those observed in early and positive superhumps. Our findings are consistent with a tilted disk model as the light source of negative superhumps.

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Akira Imada, Kenshi Yanagisawa, Nobuyuki Kawai. 2018-05-07. On the Colour Variations of Negative Superhumps. https://doi.org/10.1093/pasj%2Fpsy068

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