Kepler-1624b Has No Significant Transit Timing Variations

TL;DR

This study reanalyzed Kepler-1624b's transit timing variations with extended data and found no significant evidence for additional planetary companions, emphasizing careful analysis of low-amplitude TTV signals.

Contribution

It provides a comprehensive reanalysis of Kepler-1624b's TTVs using extended datasets, demonstrating the importance of thorough analysis for low-amplitude signals.

Findings

TTV amplitude is weaker in the updated analysis.

Bayes factor favors a one-planet model.

No significant evidence for a nearby non-transiting companion.

Abstract

It is relatively rare for gas giant planets to have resonant or near-resonant companions, but these systems are particularly useful for constraining planet formation and migration models. In this study, we examine Kepler-1624b, a sub-Saturn orbiting an M dwarf that was previously found to exhibit transit timing variations with an amplitude of approximately 2 minutes, suggesting the presence of a nearby non-transiting companion. We reanalyze the transits from archival Kepler data and extend the TTV baseline by 11 years by combining TESS data with three new ground-based transit observations from Palomar and Las Cumbres Observatories. We jointly fit these datasets and find that the TTV amplitude is significantly weaker in our updated analysis. We calculate the Bayes factor for a one-planet versus two-planet model and find that the one-planet model is preferred. Our results highlight the need for careful analysis of systems with relatively low amplitude TTV signals that are identified in large automated catalogs.