Period variability in the pulsating extreme helium stars V652 Her and BX Cir

Loading...
Thumbnail Image

Date

2024

Journal Title

Journal ISSN

Volume Title

Publisher

Oxford University Press

Abstract

Eighteen new timings of maxima of the radially pulsating Extreme Helium star, V652 Her, obtained during 2010-2023 are reported, together with 26 new timings of the very similar star, BX Cir, during 2014-2023. New ephemerides are derived from baselines which are now substantially longer than previously published. Both ephemerides are thus refined and, in the case of BX Cir, we find for the first time evidence of a cubic term (the period change rate is decreasing). BX Cir data from the Transiting Exoplanet Survey Satellite (TESS) reveals a previously unreported frequency near 65 μHz (period ∼0.179 d) with amplitude ∼0.002 mag.

Description

Keywords

Chemically peculiar, V652 Her, BX Cir, Stars: oscillations, NATURAL SCIENCES::Physics::Astronomy and astrophysics::Formation and development of stars

Citation

Kilkenny, D., Worters, H.L. and Baran, A.S., 2024. Period variability in the pulsating Extreme Helium stars V652 Her and BX Cir. Monthly Notices of the Royal Astronomical Society, 527(3), pp.8402-8408.