Revisiting bright δ Scuti stars and their period–luminosity relation with TESS and Gaia DR3

• DOI: 10.1093/mnras/stac2132
• Publication Date: 2022-07-31T07:40:27Z
• Authors: Natascha Barac; Timothy R Bedding; Simon J Murphy; Daniel R Hey
• Keywords: RR Lyrae variable; Asteroseismology; Hertzsprung–Russell diagram; Stellar pulsation; Variable star; Instability strip

ABSTRACT We have used NASA’s TESS mission to study catalogued δ Scuti stars. examined light curves for 434 stars, including many which few previous observations exist. found that 62 are not pulsators, with most instead showing variability from binarity. For the 372 we provide a catalogue of period and amplitude dominant pulsation mode. Using Gaia DR3 parallaxes, place stars in period–luminosity (P–L) diagram confirm findings lie on ridge corresponds fundamental radial mode, others fall second is factor two shorter period. This seen more clearly than before, thanks revised periods distances. demonstrate value P–L distinguishing short-period RR Lyrae find several new examples high-frequency regular sequences overtone modes, XX Pyx 29 Cyg. Finally, revisit sample observed by Kepler show they follow tight period–density relation, constant mode Q = 0.0315 d.