TESS photometry of extreme helium stars PV Tel and V821 Cen. (29th April 2020)

• Record Type: Journal Article
• Authors: Jeffery, C Simon; Barentsen, Geert; Handler, Gerald
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 495:Number 1(2020)
• Page Start: L135
• Page End: L138
• Publication Date: 2020-04-29
• Subjects: stars: chemically peculiar -- stars: early-type -- stars: individual: PV Tel, V821 Cen -- stars: supergiants -- stars: variables: general; Astronomy -- Research -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnrasl/slaa075
• Languages: English
• ISSNs: 1745-3933

Abstract

ABSTRACT: PV Tel variables are extreme helium (EHe) stars known to be intrinsic light and velocity variable on characteristic time-scales of 0.1–25 d. With two exceptions, they are best described as irregular. Light curves have invariably been obtained from single-site terrestrial observatories. We present Transiting Exoplanet Survey Satellite observations of two bright EHe stars, Popper's star (V821 Cen) and Thackeray's star (PV Tel). PV Tel is variable on time-scales previously reported. V821 Cen is proven to be variable for the first time. Neither light curve shows any evidence of underlying regularity. Implications are considered.