Examining the detectability of ringing on highly eccentric exoplanets

Abstract

Eccentric exoplanets offer an opportunity to study the response of an atmosphere to changing thermal forcing and the robustness of the super-rotating equatorial jet seen on tidally locked hot Jupiters. However, the atmospheric dynamics on eccentric planets strongly depend on the planetary rotation period, which is difficult to constrain observationally. The ringing phenomenon, whereby the observed emission increases and decreases after the periastron passage as the flash-heated hemisphere rotates into and out of view, can provide a tight constraint on rotation. We studied five highly eccentric transiting exoplanets HAT-P-2 b, HD 80606 b, TOI-3362 b, TOI-4127 b and HD 17156 b to find which displays strong ringing signals that are sufficiently strong for the James Webb Space Telescope (JWST) to detect. We implemented the treatment of eccentricity and non-synchronous rotation in the non-grey climate model expeRT/MITgcm and generated synthetic light curves. We find four detectable ringing peaks on HD 80606 b and some undetectable ringing on TOI-4127 b and HD 17156 b. The lack of clouds, photo-chemistry and obliquity in our models may have led us to overestimate the amplitude of the ringing however. The strength of the ringing signal is mostly determined by the eccentricity, planetary rotation period, planet-to-star radius ratio and apparent magnitude of the system. We searched for more exoplanets that could show ringing but found no candidates as promising as HD 80606 b. We recommend prioritising HD 80606 b as a target for ringing with JWST. A baseline of five days after the periastron passage would capture three ringing peaks, which is sufficient to tightly constrain the planetary rotation period. An extension to seven days would add a fourth peak, which would allow us to verify the rotation period.

11 pages, 8 figures

References in corpus (29)

• petitRADTRANS: a Python radiative transfer package for exoplanet characterization and retrieval
• Photochemically-produced SO${}_2$ in the atmosphere of WASP-39b
• Early Release Science of the exoplanet WASP-39b with JWST NIRISS
• Retrieving scattering clouds and disequilibrium chemistry in the atmosphere of HR 8799e
• HD147506b: A Super-Massive Planet in an Eccentric Orbit Transiting a Bright Star
• Early Release Science of the exoplanet WASP-39b with JWST NIRCam
• The Atmospheric Circulation of the Hot Jupiter WASP-43b: Comparing Three-Dimensional Models to Spectrophotometric Data
• The 4.5 $\mu$m full-orbit phase curve of the hot Jupiter HD 209458b
• Photometric and spectroscopic detection of the primary transit of the 111-day-period planet HD 80606 b
• Five Intermediate-Period Planets from the N2K Sample
• SO2, silicate clouds, but no CH4 detected in a warm Neptune
• The Precision of Mass Measurements Required for Robust Atmospheric Characterization of Transiting Exoplanets
• The UK Met Office GCM with a sophisticated radiation scheme applied to the hot Jupiter HD 209458b
• 3D Structures of equatorial waves and the resulting superrotation in the atmosphere of a tidally locked hot Jupiter
• On the origin of eccentricities among extrasolar planets
• Idealised simulations of the deep atmosphere of hot jupiters: Deep, hot, adiabats as a robust solution to the radius inflation problem
• Atmospheric Circulation of Eccentric Hot Jupiter HAT-P-2b
• Grid of Pseudo-2D Chemistry Models for Tidally-Locked Exoplanets. I. The Role of Vertical and Horizontal Mixing
• The Photoeccentric Effect and Proto-Hot Jupiters II. KOI-1474.01, a candidate eccentric planet perturbed by an unseen companion
• Spectroscopic parameters for solar-type stars with moderate/high rotation. New parameters for 10 planet-hosts
• A New Analysis of 8 Spitzer Phase Curves and Hot Jupiter Population Trends: Qatar-1b, Qatar-2b, WASP-52b, WASP-34b, and WASP-140b
• Atmospheres on Nonsynchronized Eccentric-tilted Exoplanets I: Dynamical Regimes
• Models of Warm Jupiter Atmospheres: Observable Signatures of Obliquity
• No evidence for radius inflation in hot Jupiters from vertical advection of heat
• Atmospheres on Nonsynchronized Eccentric-tilted Exoplanets II: Thermal Light Curves
• TOI-4562 b: A highly eccentric temperate Jupiter analog orbiting a young field star
• Utilizing a global network of telescopes to update the ephemeris for the highly eccentric planet HD 80606 b and to ensure the efficient scheduling of JWST
• A High-Eccentricity Warm Jupiter Orbiting TOI-4127
• Warm Jupiters Beyond the Tidal Synchronization Limit May Exhibit a Wide Range of Secondary Eclipse Depths

Cited by in corpus (1)

• Seasonal Changes in the Atmosphere of HD 80606b Observed with JWST's NIRSpec/G395H