Outburst characteristics of the dwarf nova SDSS J073208.11+413008.7

TL;DR

This study documents the first confirmed superoutburst of dwarf nova SDSS J073208.11+413008.7, revealing its classification as an SU UMa type, with detailed analysis of superhump period evolution, amplitude variations, and outburst frequency.

Contribution

It provides the first observational confirmation of a superoutburst in SDSS J073208.11+413008.7 and analyzes superhump period changes and outburst recurrence, expanding knowledge of this dwarf nova's behavior.

Findings

Superoutburst lasted about 14 days with nearly 5 magnitude amplitude.

Superhump period showed significant evolution during the outburst.

Star exhibits frequent outbursts with an estimated period of 215 days.

Abstract

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.