Are Hot Jupiters Tidally Disrupted During Stellar Main Sequence?

Once hot Jupiters (HJs) reach their very close orbits, they are expected to experience orbital decay due to tidal interactions with their host star. However, the strength of tidal dissipation is highly uncertain, and it remains an open question whether HJs are tidally disrupted during the stellar main sequence. A previous study found that HJ hosts have a smaller Galactic total velocity dispersion than their field star counterparts, which they interpreted as evidence of tidal disruption. We revisit this study and find that, after using the more reliable vertical velocity dispersion (σW) as the age indicator and accounting for the heterogeneity and anisotropy of their HJ sample, the kinematic age difference between their HJ hosts and matched field stars is significantly reduced. As an independent check, we collect HJs newly discovered by TESS and find that their σW is statistically similar to that of matched field stars. We also find no statistically significant σW difference between the field stars and the theoretically vulnerable ultra-hot Jupiters with P < 2 d. Our results suggest that, after accounting for systematics in the age–velocity dispersion relation, there is no statistically strong evidence from the stellar kinematics that a large fraction of hot Jupiters around Sun-like stars are tidally destroyed during the stellar main sequence.

Improvements to AI Systems:

1. Kinematic Age-Dating with Anisotropy Correction

• Improvement: Enhance stellar population models to use vertical velocity dispersion (σW) instead of total velocity dispersion, and incorporate corrections for sample heterogeneity and anisotropy (e.g., Galactic position, metallicity, selection biases).

• Improved AI capability: An AI system can now estimate stellar ages with higher reliability for exoplanet-host stars, reducing false evolutionary conclusions by automatically flagging kinematic biases in heterogeneous samples.

2. Automated Sample-Matching for Controlled Comparisons

• Improvement: Implement a matching algorithm that pairs exoplanet-host stars to field stars based on multiple parameters (e.g., Teff, [Fe/H], log g, spatial location) while explicitly controlling for kinematic anisotropy.

• Improved AI capability: The system can generate statistically robust control samples, minimizing systematic age–velocity relation errors in population studies (e.g., detecting tidal disruption or other dynamical processes).

3. Bayesian Hypothesis Testing for Tidal Disruption

• Improvement: Integrate a Bayesian framework that compares models of “no tidal disruption” vs. “significant tidal disruption” using σW distributions, with priors on stellar age–velocity relations and orbital decay timescales.

• Improved AI capability: The AI can output posterior probabilities for disruption fractions, rather than binary significance tests, and automatically update these as new exoplanet catalogs (e.g., TESS) are ingested.

4. Cross-Survey Data Fusion for New Exoplanet Catalogs

• Improvement: Build a pipeline that merges newly discovered TESS hot Jupiters with Gaia kinematic data, applying consistent quality cuts and correcting for selection effects (e.g., detection biases toward shorter periods).

• Improved AI capability: The system can continuously re-evaluate kinematic age differences in near-real-time as new planets are discovered, providing early warnings of potential evolutionary anomalies.

5. Simulation-Informed Prior for Tidal Dissipation Strength

• Improvement: Train a neural network on synthetic populations of hot Jupiters with varying tidal dissipation parameters (Q′), then use its predictions as priors for observed σW comparisons.

• Improved AI capability: The AI can infer posterior constraints on Q′ from kinematic data alone, even when individual orbital decay is unobservable, and predict which stellar populations should show depletion of ultra-hot Jupiters.

6. Uncertainty-Aware Kinematic Comparison Tool

• Improvement: Develop a statistical test that propagates measurement errors in σW, sample size, and selection biases into a single “kinematic difference significance” metric, with bootstrap resampling.

• Improved AI capability: The system can output confidence intervals for age differences, preventing overinterpretation of marginal signals (as the paper demonstrates for P < 2 d planets).

What the Improved AI System Can Do:

• Automatically re-analyze any exoplanet-host sample against field stars, producing bias-corrected kinematic age estimates and disruption probabilities.

• Flag when a claimed tidal-disruption signal is likely a systematic artifact (e.g., anisotropy or sample heterogeneity).

• Provide real-time updates on hot Jupiter survival rates as new TESS and Gaia data releases arrive.

• Serve as a general-purpose tool for testing any stellar dynamical hypothesis using kinematic age indicators, with built-in corrections for Galactic structure.

Once hot Jupiters (HJs) reach their very close orbits, they are expected to experience orbital decay due to tidal interactions with their host star. However, the strength of tidal dissipation is highly uncertain, and it remains an open question whether HJs are tidally disrupted during the stellar main sequence. A previous study found that HJ hosts have a smaller Galactic total velocity dispersion than their field star counterparts, which they interpreted as evidence of tidal disruption. We revisit this study and find that, after using the more reliable vertical velocity dispersion (sigma W) as the age indicator and accounting for the heterogeneity and anisotropy of their HJ sample, the kinematic age difference between their HJ hosts and matched field stars is significantly reduced. As an independent check, we collect HJs newly discovered by TESS and find that their sigma W is statistically similar to that of matched field stars. We also find no statistically significant sigma W difference between the field stars and the theoretically vulnerable ultra-hot Jupiters with P<2 d. Our results suggest that, after accounting for systematics in the age--velocity dispersion relation, there is no statistically strong evidence from the stellar kinematics that a large fraction of hot Jupiters around Sun-like stars are tidally destroyed during the stellar main sequence.