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arXiv · 1910.12069

Analysis of spiral structure in the accretion disc of the novalike Cataclysmic Variable EC21178--5417

R. Ruiz-Carmona·Z. N. Khangale·P. A. Woudt·P. J. Groot
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Abstract

We present an extensive Doppler tomography study of the eclipsing novalike EC21178--5417, which exhibits the classic accretion disc signature in the form of double-peak emission lines in its spectrum. Doppler tomograms confirm the presence of a strong, two-armed spiral pattern visible in the majority of the spectral lines studied. This makes EC21178--5417 one of the very few novalikes that show spiral structure in their discs. We also report night-to-night changes in the position and relative strength of the spiral arms, revealing fluctuations on the conditions in the accretion disc.

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R. Ruiz-Carmona, Z. N. Khangale, P. A. Woudt, P. J. Groot. 2019-10-26. Analysis of spiral structure in the accretion disc of the novalike Cataclysmic Variable EC21178--5417. https://doi.org/10.1093/mnras%2Fstz2839

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