RR Pictoris: an old nova showing superhumps and QPOs

TL;DR

This study presents detailed photometric observations of RR Pictoris, revealing superhumps, QPOs, and refining orbital period measurements, contributing to understanding the variability mechanisms in old novae.

Contribution

It reports the detection of superhumps, QPOs, and refines the orbital period of RR Pic, providing new insights into its variability characteristics.

Findings

Detection of superhump period at 3.78h

Presence of 13-minute QPOs

Refined orbital period consistent with previous data

Abstract

We present time-resolved V-photometry of the old nova RR Pic. Apart from the hump-like variability, the light curves show the strong flickering and random variation typical for RR Pic. We do not find any convincing evidence for the previously reported eclipse. The extrapolated eclipse phase coincides with a broad minimum, but comparing the overall shape of the light curve suggests that the eclipse should actually be located around phase 0.2. The orbital period which we derive from these data agrees well with the old one, any uncertainty is too small to account for the possible phase shift. Apart from the 3.48h period, which is usually interpreted as the orbital one, we find an additional period at P=3.78h, which we interpret as the superhump period of the system; the corresponding precession period at 1.79d is also present in the data. We also find indications for the presence of a 13min quasi-periodic oscillation.