Curious Variables Experiment (CURVE). CCD Photometry of V419 Lyr in its 2006 July Superoutburst

TL;DR

This study presents detailed CCD photometry of the dwarf nova V419 Lyr during its 2006 superoutburst, revealing a high rate of superhump period decrease and characteristics typical of long-period SU UMa systems.

Contribution

First detailed CCD photometry of V419 Lyr's superoutburst, measuring superhump period evolution and amplitude changes in a long-period dwarf nova.

Findings

Superoutburst lasted at least 15 days with ~3.5 mag amplitude.

Superhump period decreased rapidly during the plateau phase.

No clear secondary humps observed, typical for long-period systems.

Abstract

We report extensive photometry of the dwarf nova V419 Lyr throughout its 2006 July superoutburst till quiescence. The superoutburst with amplitude of ~3.5 magnitude lasted at least 15 days and was characterized by the presence of clear superhumps with a mean period of Psh=0.089985(58) days (129.58+-0.08 min). According to the Stolz-Schoembs relation, this indicates that the orbital period of the binary should be around 0.086 days i.e. within the period gap. During the superoutburst the superhump period was decreasing with the rate of dotP/Psh=-24.8(2.2)*10^-5, which is one of the highest values ever observed in SU UMa systems. At the end of the plateau phase, the superhump period stabilized at a value of 0.08983(8) days. The superhump amplitude decreased from 0.3 mag at the beginning of the superoutburst to 0.1 mag at its end. In the case of V419 Lyr we have not observed clear secondary humps, which seems to be typical for long period systems.