Variability of Classical T Tauri Systems (CTTS) occurs over a vast range of timescales. CTTS in particular are subject to variability caused by accretion shocks which can occur stochastically, periodically, or quasi-periodically on timescales over a few days. The detectability of young planets within these systems is likely hampered by activity; therefore, it is essential that we understand the origin of young star variability over a range of timescales to help disentangle stellar activity from signatures of planetary origin. We present analysis of the stochastic small-amplitude photometric variability in the K2 lightcurve of CI Tau occurring on timescales of ≲1 d. We find the amplitude of this variability exhibits the same periodic signatures as detected in the large-amplitude variability, indicating that the physical mechanism modulating these brightness features is the same. The periods detected are also in agreement with the rotation period of the star (∼6.6 d), and orbital period of the planet (∼9.0 d) known to drive pulsed accretion onto the star.
@article{arxiv.2011.05388,
title = {Amplitude Modulation of Short-Timescale Hot Spot Variability},
author = {Lauren I. Biddle and Joe Llama and Andrew Collier Cameron and Lisa A. Prato and Moira M. Jardine and Christopher M. Johns-Krull},
journal= {arXiv preprint arXiv:2011.05388},
year = {2021}
}