VSX J074727.6+065050: a new WZ Sagittae star in Canis minor

TL;DR

This paper reports the discovery and detailed photometric analysis of a new WZ Sagittae-type dwarf nova, VSX J074727.6+065050, highlighting its superoutburst characteristics, superhump period changes, and echo outbursts.

Contribution

It provides the first detailed observational data on this star's superoutburst, including superhump period evolution and evidence of its classification as a WZ Sge-type dwarf nova.

Findings

Superoutburst lasted over 80 days with an 8-magnitude amplitude.

Detected superhumps with period Psh = 0.06070(6) d during plateau.

Observed period increase and echo outbursts indicating WZ Sge characteristics.

Abstract

We present photometry of the first reported superoutburst of the dwarf nova VSX J074727.6+065050 during 2008 January and February. At its brightest the star reached magnitude 11.4 and this was followed by a slow decline at 0.09 mag/d for 19 days, corresponding to the plateau phase. There was then a rapid decline at 1.66 mag/d to a temporary minimum at magnitude 16.6 where it stayed for 2 to 3 days after which there were six remarkable echo outbursts before the star gradually faded back towards quiescence at ~magnitude 19.5. The overall outburst amplitude was at least 8 magnitudes and it lasted more than 80 days. During the plateau phase we observed common superhumps with Psh = 0.06070(6) d, but the period increased to Psh = 0.06151(5) d coinciding with the end of the plateau phase and the onset of the rapid decline. This corresponds to a continuous period change with P^dot = +4.4(9) x 10-5. During the echo outbursts there was a superhump regime with Psh = 0.06088(49) d. Evidence is presented which is consistent with the star being a member of the WZ Sge family of dwarf novae.