High Cadence Time-Series Photometry of V1647 Orionis

TL;DR

This study provides high cadence photometry of V1647 Orionis during its outbursts, revealing flicker noise and a possible short-lived stellar oscillation linked to accretion activity.

Contribution

It presents detailed time-series photometry during different outburst phases and identifies potential stellar oscillations associated with accretion rate changes.

Findings

Detection of flicker noise in the power spectrum.

Identification of a 0.13-day periodic signal in 2003.

Possible link between short-lived oscillations and accretion surges.

Abstract

We present high cadence (1-10 hr^-1) time-series photometry of the eruptive young variable star V1647 Orionis during its 2003-2004 and 2008-2009 outbursts. The 2003 light curve was obtained mid-outburst at the phase of steepest luminosity increase of the system, during which time the accretion rate of the system was presumably continuing to increase toward its maximum rate. The 2009 light curve was obtained after the system luminosity had plateaued, presumably when the rate of accretion had also plateaued. We detect a 'flicker noise' signature in the power spectrum of the lightcurves, which may suggest that the stellar magnetosphere continued to interact with the accretion disk during each outburst event. Only the 2003 power spectrum, however, evinces a significant signal with a period of 0.13 d. While the 0.13 d period cannot be attributed to the stellar rotation period, we show that it may plausibly be due to short-lived radial oscillations of the star, possibly caused by the surge in the accretion rate.