Mutual Inclination of Ultra-short-period Planets with Time-varying Stellar <i>J</i> <sub>2</sub> Moments

dc.contributor.authorChen, Chen
dc.contributor.authorLi, Gongjie
dc.contributor.authorPetrovich, Cristobal
dc.date.accessioned2025-01-20T21:08:15Z
dc.date.available2025-01-20T21:08:15Z
dc.date.issued2022
dc.description.abstractSystems with ultra-short-period (USP) planets tend to possess larger mutual inclinations compared to those with planets located farther from their host stars. This could be explained due to precession caused by stellar oblateness at early times when the host star was rapidly spinning. However, stellar oblateness reduces over time due to the decrease in the stellar rotation rate, and this may further shape the planetary mutual inclinations. In this work, we investigate in detail how the final mutual inclination varies under the effect of a decreasing J (2). We find that different initial parameters (e.g., the magnitude of J (2) and planetary inclinations) will contribute to different final mutual inclinations, providing a constraint on the formation mechanisms of USP planets. In general, if the inner planets start in the same plane as the stellar equator (or coplanar while misaligned with the stellar spin axis), the mutual inclination decreases (or increases then decreases) over time due to the decay of the J (2) moment. This is because the inner orbit typically possesses less orbital angular momentum than the outer ones. However, if the outer planet is initially aligned with the stellar spin while the inner one is misaligned, the mutual inclination nearly stays the same. Overall, our results suggest that either USP planets formed early and acquired significant inclinations (e.g., greater than or similar to 30 degrees with its companion or greater than or similar to 10 degrees with its host star spin axis for Kepler-653 c) or they formed late (greater than or similar to Gyr) when their host stars rotated slower.
dc.fuente.origenWOS
dc.identifier.doi10.3847/1538-4357/ac6024
dc.identifier.eissn1538-4357
dc.identifier.issn0004-637X
dc.identifier.urihttps://doi.org/10.3847/1538-4357/ac6024
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/93466
dc.identifier.wosidWOS:000790525200001
dc.issue.numero1
dc.language.isoen
dc.revistaAstrophysical journal
dc.rightsacceso restringido
dc.subject.ods13 Climate Action
dc.subject.odspa13 Acción por el clima
dc.titleMutual Inclination of Ultra-short-period Planets with Time-varying Stellar <i>J</i> <sub>2</sub> Moments
dc.typeartículo
dc.volumen930
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files