@article{c36180f65e554f4d97197f3eb5e9dfaf,
title = "Multiple variability time-scales of the early nitrogen-rich Wolf-Rayet star WR 7",
abstract = "We present the analysis of the optical variability of the early, nitrogen-rich Wolf-Rayet (WR) star WR 7. The analysis of multisector Transiting Exoplanet Survey Satellite (TESS) light curves and high-resolution spectroscopic observations confirm multiperiodic variability that is modulated on time-scales of years. We detect a dominant period of 2.6433 ± 0.0005 d in the TESS sectors 33 and 34 light curves in addition to the previously reported high-frequency features from sector 7. We discuss the plausible mechanisms that may be responsible for such variability in WR 7, including pulsations, binarity, co-rotating interaction regions (CIRs), and clumpy winds. Given the lack of strong evidence for the presence of a stellar or compact companion, we suggest that WR 7 may pulsate in quasi-coherent modes in addition to wind variability likely caused by CIRs on top of stochastic low-frequency variability. WR 7 is certainly a worthy target for future monitoring in both spectroscopy and photometry to sample both the short (≲1 d) and long (≳1000 d) variability time-scales.",
keywords = "Outflows, Stars: Atmospheres, Stars: Evolution, Stars: Individual: Wr 7, Stars: Winds, Stars: Wolft-rayet",
author = "Toal{\'a}, \{J. A.\} and Bowman, \{D. M.\} and \{Van Reeth\}, T. and H. Todt and K. Dsilva and T. Shenar and G. Koenigsberger and S. Estrada-Dorado and Oskinova, \{L. M.\} and Hamann, \{W. R.\}",
note = "Publisher Copyright: {\textcopyright} 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.",
year = "2022",
month = aug,
day = "1",
doi = "10.1093/mnras/stac1455",
language = "אנגלית",
volume = "514",
pages = "2269--2277",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "2",
}