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Unusual Phase Reversal of Superhumps in ER Ursae Majoris

T. Kato·D. Nogami·S. Masuda
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Abstract

We studied the evolution of superhumps in the peculiar SU UMa-type dwarf nova, ER UMa. Contrary to the canonical picture of the SU UMa-type superhump phenomena, the superhumps of ER UMa show an unexpected phase reversal during the very early stage (~5 d after the superoutburst maximum). We interpret that a sudden switch to so-called late superhumps occurs during the very early stage of a superoutburst. What had been believed to be (ordinary) superhumps during the superoutburst plateau of ER UMa were actually late superhumps. The implication of this discovery is briefly discussed.

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T. Kato, D. Nogami, S. Masuda. 2002-11-24. Unusual Phase Reversal of Superhumps in ER Ursae Majoris. https://doi.org/10.1093/pasj%2F55.2.l7

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