A search for transit timing variations in the HATS-18 planetary system

Abstract

HATS-18b is a transiting planet with a large mass and a short orbital period, and is one of the best candidates for the detection of orbital decay induced by tidal effects. We present extensive photometry of HATS-18 from which we measure 27 times of mid-transit. Two further transit times were measured from data from the Transiting Exoplanet Survey Satellite (TESS) and three more taken from the literature. The transit timings were fitted with linear and quadratic ephemerides and an upper limit on orbital decay was determined. This corresponds to a lower limit on the modified stellar tidal quality factor of $Q_{\star }^{\prime }>10^{5.11\pm 0.04}$. This is at the cusp of constraining the presence of enhanced tidal dissipation due to internal gravity waves. We also refine the measured physical properties of the HATS-18 system, place upper limits on the masses of third bodies, and compare the relative performance of TESS and the 1.54-m Danish Telescope in measuring transit times for this system.

Accepted for publication in MNRAS. 12 pages, 4 tables, 6 figures. This is the authors' version of the accepted paper

References in corpus (24)

• Modules for Experiments in Stellar Astrophysics (MESA)
• The Transiting Exoplanet Survey Satellite
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• The Dartmouth Stellar Evolution Database
• Achieving better than 1 minute accuracy in the Heliocentric and Barycentric Julian Dates
• DHP Framework: Digital Health Passports Using Blockchain -- Use case on international tourism during the COVID-19 pandemic
• Tidal dissipation in stars and giant planets
• Tidal Evolution of Close-in Extra-Solar Planets
• Homogeneous studies of transiting extrasolar planets. I. Light curve analyses
• Falling Transiting Extrasolar Giant Planets
• Homogeneous studies of transiting extrasolar planets. II. Physical properties
• Stability Limits in Extra-solar Planetary Systems
• Tidal dissipation in evolving low-mass and solar-type stars with predictions for planetary orbital decay
• Indications for an influence of Hot Jupiters on the rotation and activity of their host stars
• A transit timing analysis of nine RISE light curves of the exoplanet system TrES-3
• A comparison of gyrochronological and isochronal age estimates for transiting exoplanet host stars
• WASP-4b Arrived Early for the TESS Mission
• High-precision photometry by telescope defocussing. VI. WASP-24, WASP-25 and WASP-26
• Discrepancies between isochrone fitting and gyrochronology for exoplanet host stars?
• Searching For Rapid Orbital Decay of WASP-18b
• The long-term stability of extrasolar system HD 37124. Numerical study of resonance effects
• Dynamical tides in exoplanetary systems containing Hot Jupiters: confronting theory and observations
• Transiting Exoplanet Monitoring Project (TEMP). II. Refined System Parameters and Transit Timing Analysis of HAT-P-33b
• Homogeneous Transit Timing Analyses of Ten Exoplanet Systems

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