Discovery of new TESS pulsating hot subdwarfs

¹ Astronomical Observatory, Jagiellonian University, ul. Orla 171, PL-30-244 Krakow, Poland
e-mail: jk@oa.uj.edu.pl
² South African Astronomical Observatory, PO Box 9, Observatory, Cape Town, South Africa
e-mail: labsaao.ac.za

Received: 8 December 2021
Accepted: 21 March 2022

Abstract

Aims. This work is dedicated to a search for new pulsating hot subdwarfs in TESS photometric data which could have been missed in previous searches.

Methods. By matching catalogues of hot subdwarfs with TESS targets and using luminosities from Gaìa parallaxes, a list of 1389 candidate hot subdwarfs observed by TESS was created. The periodograms of these stars were inspected, and the stars were classified according to variability type.

Results. An updated catalogue of all known pulsating hot subdwarfs is presented. A number of probable pulsating binaries have been identified, which might prove useful for verifying the asteroseismic masses. The mean masses of p- and g-mode pulsators are estimated from the stellar parameters.

Conclusions. A list of 63 previously unknown pulsating hot subdwarfs observed by TESS is presented. More than half of the stars previously identified as pure p-mode pulsators are found to have frequencies in the g-mode region as well. As a result, hybrid p- and g-mode pulsators occur over the whole instability strip.