J/AJ/159/83ivo://CDS.VizieR/J/AJ/159/83doi:10.26093/cds/vizier.51590083CDSKain I.J.Newton E.R.Dittmann J.A.Irwin J.M.Mann A.W.Thao P.C.,Charbonneau D.Winters J.G.2020-07-21T12:57:35Z2020-05-04T08:24:26ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frm-starsexoplanetsinfrared-photometryvisible-astronomyphotometryThe 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.2020AJ....159...83Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/159/83CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/331/81 : Hyades membership (Perryman+ 1998)J/A+A/367/111 : A Hipparcos study of the Hyades cluster (de+, 2001)J/ApJ/709/168 : Eccentric orbits in exoplanets (Anglada-Escude+, 2010)J/ApJ/795/161 : Activity & rotation in Praesepe and the Hyades (Douglas+, 2014)J/ApJS/216/7 : Planets Around Low-Mass Stars (PALMS). IV. (Bowler+, 2015)J/ApJ/818/153 : MEarth photometry: nearby M-dwarf magnitudes (Dittmann+, 2016)J/ApJ/821/93 : Rotation & Galactic kinematics of mid M dwarfs (Newton+, 2016)J/A+A/592/A13 : HD 219828 radial velocity curve (Santos+, 2016)J/ApJ/825/19 : Mass-radius relationship for planets with Rp<4 (Wolfgang+,2016)J/ApJ/836/167 : K2 planetary syst. around low-mass stars. I. (Dressing+, 2017)J/AJ/154/142 : Corrected photometry for GJ1132 for eclipses (Dittmann+, 2017)J/AJ/154/224 : Transiting planets in young clusters from K2 (Rizzuto+, 2017)J/AJ/156/140 : 4 new eclipsing mid M-dwarf systems from MEarth (Irwin+, 2018)J/AJ/156/217 : Stellar properties for M dwarfs in MEarth-South (Newton+, 2018)J/A+A/610/A20 : HITEP. II. Transiting exoplanets imaging (Evans+, 2018)J/A+A/613/A41 : 5 exoplanet light and RV curves (Mancini+, 2018)J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diagrams (Gaia Collaboration, 2018)http://www.cfa.harvard.edu/MEarth : MEarth project home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/159/83https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/159/83http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/159/83https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/159/83https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/159/83http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/159/83GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/159/83/fig1*MEarth transits photometryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintN[87/192] Transit numbermeta.idintBJD[2457365/2457732] Barycentric Julian Datedtime.epochdoubleDmag[-0.28/0.08] Differential magnitudemagphot.mag;arith.diffdoublee_Dmag[0.002/0.09] Uncertainty in Dmagmagstat.error;phot.mag;arith.diffdoubleTel[1/18] MEarth telescope identifiermeta.id;instr.telintJ/AJ/159/83/fig2Stellar rotational variability over three yearsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2457366/2458335] Barycentric Julian Datedtime.epochdoublemag[-0.06/0.05] Relative brightnessmagphot.flux;arith.ratiodoublee_mag[0.002/0.03] Uncertainty in magmagstat.error;phot.magdouble