* Astronomy

Title: Outburst characteristics of the dwarf nova SDSS J073208.11+413008.7
Authors: Jeremy Shears, Robert Koff, Richard Sabo, Bart Staels, William Stein, Patrick Wils

We report unfiltered photometry during the first confirmed superoutburst of the recently discovered dwarf nova, SDSS J073208.11+413008.7 and conclude that it is a member of the SU UMa family. At its brightest, the star was magnitude 15.7. The outburst amplitude was nearly 5 magnitudes and it lasted about 14 days. We determined the mean superhump period from our first 3 nights of observations as Psh = 0.07979(19) d, however analysis of the O-C residuals showed a dramatic evolution in Psh during the outburst. During the first part of the plateau phase the period increased with dPsh/dt = +2.81(9) x 10^-3. There was then an abrupt change following which the period decreased with dPsh/dt = -0.78(12)x 10^-3.The amplitude of the superhumps also varied, with a maximum amplitude near the beginning of the outburst and a second maximum later in the plateau phase. Analysis of archival data suggests that the star undergoes frequent outbursts: we identified 10 normal outbursts and at least 3 likely superoutbursts over a 4.5 year interval. We estimate that the superoutburst period is around 215 days.

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