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The Dwarf Nova PQ Andromedae

Joseph Patterson·John Thorstensen·Eve Armstrong·Arne Henden·Robert Hynes
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Abstract

We report a photometric study of the WZ Sagittae-type dwarf nova PQ Andromedae. The light curve shows strong (0.05 mag full amplitude) signals with periods of 1263(1) and 634(1) s, and a likely double-humped signal with P=80.6(2) min. We interpret the first two as nonradial pulsation periods of the underlying white dwarf, and the last as the orbital period of the underlying binary. We estimate a distance of 150(50) pc from proper motions and the two standard candles available: the white dwarf and the dwarf-nova outburst. At this distance, the K magnitude implies that the secondary is probably fainter than any star on the main sequence -- indicating a mass below the Kumar limit at 0.075 M_sol. PQ And may be another "period bouncer", where evolution now drives the binary out to longer period.

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Joseph Patterson, John Thorstensen, Eve Armstrong, Arne Henden, Robert Hynes. 2005-06-07. The Dwarf Nova PQ Andromedae. https://doi.org/10.1086/432492

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