Superhump periods in the UGSU-type dwarf nova SDSSp J082409.73+493124.4

David Boyd; Jeremy Shears; Robert Koff

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arXiv · 0707.1865

Superhump periods in the UGSU-type dwarf nova SDSSp J082409.73+493124.4

David Boyd·Jeremy Shears·Robert Koff

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Abstract

We present observations and analysis of the first reported superoutburst of the dwarf nova SDSSp J082409.73+493124.4 during February/March 2007. From a maximum observed magnitude of 15.4C it declined at 0.09 mag/d for 7 days, flattened out around magnitude 16 for a further 5 days and then returned rapidly to quiescence at magnitude 19.4. The flattening of the light curve late in the outburst was not associated with a re-growth of superhumps. For the first 5 days we observed common superhumps with period 0.06954(5) d, thus confirming its classification as a UGSU-type dwarf nova. This was followed by a phase transition to late superhumps with period 0.06921(6) d. We found a small but persistent signal at 0.0687(6) d which we interpret as the orbital period.

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David Boyd, Jeremy Shears, Robert Koff. 2007-07-12. Superhump periods in the UGSU-type dwarf nova SDSSp J082409.73+493124.4. https://arxiv.org/abs/0707.1865

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