Transit analysis for the K2-25 system

DOI

The abundance of planets with orbital periods of a few to tens of days suggests that exoplanets experience complex dynamical histories. Planets in young stellar clusters or associations have well-constrained ages and therefore provide an opportunity to explore the dynamical evolution of exoplanets. K2-25b is a Neptune-sized planet in an eccentric, 3.48day orbit around an M4.5 dwarf star in the Hyades cluster (650Myr). In order to investigate its non-zero eccentricity and tight orbit, we analyze transit timing variations (TTVs) which could reveal clues to the migration processes that may have acted on the planet. We obtain 12 nonconsecutive transits using the MEarth observatories and long-term photometric monitoring, which we combine with 10 transits from the Spitzer Space Telescope and 20 transits from K2. Tables of MEarth photometry accompany this work. We fit each transit lightcurve independently. We first investigate whether inhomogeneities on the stellar surface (such as spots or plages) are differentially affecting our transit observations. The measured transit depth does not vary significantly between transits, though we see some deviations from the fiducial transit model. We then looked for TTVs as evidence of a nontransiting perturber in the system. We find no evidence for >1M_{Earth} mass companions within a 2:1 period ratio, or for >5M{Earth}_ mass planets within a 7:2 period ratio.

Identifier
DOI http://doi.org/10.26093/cds/vizier.51590083
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/AJ/159/83
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/83
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/159/83
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/AJ/159/83
Provenance
Creator Kain I.J.; Newton E.R.; Dittmann J.A.; Irwin J.M.; Mann A.W.; Thao P.C.,Charbonneau D.; Winters J.G.
Publisher CDS
Publication Year 2020
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Exoplanet Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy