Photometric Analysis of the OGLE Heartbeat Stars

Abstract

We present an analysis of 991 heartbeat stars (HBSs) from the OGLE Collection of Variable Stars (OCVS). The sample consists of 512 objects located toward the Galactic bulge (GB), 439 in the Large Magellanic Cloud (LMC) and 40 in the Small Magellanic Cloud (SMC). We model the $I$-band OGLE light curves using an analytical model of flux variations, reflecting tidal deformations between stars. We present distributions of the model parameters that include the eccentricity, orbital inclination, and argument of the periastron, but also the period-amplitude diagrams. On the Hertzsprung-Russell (HR) diagram, our HBS sample forms two separate groups of different evolutionary status. The first group of about 90 systems, with short orbital periods ($P\lesssim 50$~days), consists of an early-type primary star lying on (or close to) the main sequence (MS). The second group of about 900 systems, with long orbital periods ($P\gtrsim 100$~days), contains a red giant (RG). The position of RG HBSs on the period-luminosity diagram strongly indicates their binary nature. They appear to be a natural extension of confirmed binary systems that include the OGLE ellipsoidal and Long Secondary Period (LSP) variables. We also present a time-series analysis leading to detection of tidally-excited oscillations (TEOs). We identify such pulsations in about 5\% of stars in the sample with a total number of 78 different modes. This first relatively large homogeneous sample of TEOs allowed us to construct a diagram revealing the correlation between the TEO's orbital harmonic number and the eccentricity of the host binary system.

22 pages (29 pages in arXiv version), 12 figures, 3 tables

References in corpus (20)

• Modules for Experiments in Stellar Astrophysics (MESA)
• A distance to the Large Magellanic Cloud that is precise to one per cent
• Scaled solar tracks and isochrones in a large region of the Z-Y plane I. From the ZAMS to the TP-AGB end for 0.15 - 2.5 Mo stars
• Physics Of Eclipsing Binaries. II. Towards the Increased Model Fidelity
• OGLE-IV: Fourth Phase of the Optical Gravitational Lensing Experiment
• YBC, a stellar bolometric corrections database with variable extinction coefficients: an application to PARSEC isochrones
• Heartbeat Stars, Tidally Excited Oscillations, and Resonance Locking
• KIC 8164262: a Heartbeat Star Showing Tidally Induced Pulsations with Resonant Locking
• KIC 3749404: A heartbeat Star with Rapid Apsidal Advance Indicative of a Tertiary Component
• Binarity as the Origin of Long Secondary Periods in Red Giant Stars
• Massive heartbeat stars from TESS. I. TESS sectors 1-16
• Tidally Trapped Pulsations in Binary Stars
• Tidally Excited Oscillations in Heartbeat Binary Stars: Pulsation Phases and Mode Identification
• The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud
• The Loudest Stellar Heartbeat: Characterizing the most extreme amplitude heartbeat star system
• The OGLE Collection of Variable Stars. Eclipsing Binaries in the Magellanic System
• $12660$ spotted stars toward the OGLE Galactic bulge fields
• The OGLE Collection of Variable Stars. One Thousand Heartbeat Stars in the Galactic Bulge and Magellanic Clouds
• Tidal Asteroseismology: Possible Evidence of Non-linear Mode Coupling in an Equilibrium State in Kepler Eclipsing Binary KIC 3230227
• Radial Velocity Curves of Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud

Cited by in corpus (9)

• Theoretical investigation of the occurrence of tidally excited oscillations in massive eccentric binary systems
• Detection of Tidally Excited Oscillations in Kepler Heartbeat Stars
• Exploring extreme brightness variations in blue supergiant MACHO 80.7443.1718: Evidence for companion-driven enhanced mass loss
• A comprehensive Gaia view of ellipsoidal and rotational red giant binaries
• Twenty-three New Heartbeat Star Systems Discovered Based on TESS Data
• KIC 7914906: An Eclipsing Heartbeat Star with Tidally Excited Oscillations and Gamma Doradus/Delta Scuti Hybrid Pulsations
• Heartbeat Stars Recognition Based on Recurrent Neural Networks: Method and Validation
• Orbital and Pulsation Analysis of 42 Heartbeat Stars Discovered in TESS Data
• A Minute-Cadence Deep Bulge Survey: First Data Release of DREAMS