J/AJ/162/57ivo://CDS.VizieR/J/AJ/162/57doi:10.26093/cds/vizier.51620057CDSSchlawin E.Su K.Y.L.Herter T.Ridden-Harper A.Apai D.2022-03-14T06:59:12Z2021-12-02T07:50:59ZCDS support team

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

cds-question@unistra.frexoplanetsk-starsinfrared-photometryvisible-astronomyThe disintegrating planet candidate K2-22b shows periodic and stochastic transits best explained by an escaping debris cloud. However, the mechanism that creates the debris cloud is unknown. The grain size of the debris as well as its sublimation rate can be helpful in understanding the environment that disintegrates the planet. Here, we present simultaneous photometry with the g band at 0.48{mu}m and KS band at 2.1{mu}m using the Large Binocular Telescope. During an event with very low dust activity, we put a new upper limit on the size of the planet of 0.71R{Earth} or 4500km. We also detected a medium depth transit that can be used to constrain the dust particle sizes. We find that the median particle size must be larger than about 0.5-1.0{mu}m, depending on the composition of the debris. This leads to a high mass-loss rate of about 3x108kg/s, which is consistent with hydrodynamic escape models. If they are produced by some alternate mechanism such as explosive volcanism, it would require extraordinary geological activity. Combining our upper limits on the planet size with the high mass-loss rate, we find a lifetime of the planet of less than 370Myr. This drops to just 21Myr when adopting the 0.02M{Earth} mass predicted from hydrodynamical models.2021AJ....162...57Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/162/57CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/559/A32 : Light curves of GJ3470b (Nascimbeni+, 2013)J/A+A/579/A19 : K2 Variable Catalogue (Armstrong+, 2015)J/A+A/579/A113 : BR light curves of GJ1214b (Nascimbeni+, 2015)J/ApJ/818/L7 : High-speed photometry obs. WD1145+017 syst. (Gansicke+, 2016)J/ApJS/222/14 : Planetary candidates 1st yr K2 mission (Vanderburg+, 2016)J/ApJ/866/99 : Radii of KIC stars & planets using Gaia DR2 (Berger+,2018)J/AJ/156/227 : Photometric observations of the K2-22 system (Colon+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/162/57https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/162/57http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/162/57https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/162/57https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/162/57http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/162/57GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/162/57/fig1Ground based photometry from UT 2020-01-25 and UT 2020-02-20recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs[Jan/Feb] Observation date in 2020, monthtime.epoch;obsnullableFiltFilter used; Ks or ginstr.setup;instr.filtercharJD[2458873/2458900] Barycentric Julian Datedtime.epochdoubleNFlux[0.98/1.02] Normalized flux in Filterphot.flux;instr.filterdoublee_NFlux[0.0006/0.003] Uncertainty in NFluxstat.errordoubleJ/AJ/162/57/fig2Ground based photometry from UT 2020-01-28recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFiltFilter used; Ks, g or openinstr.setup;instr.filtercharJD[2458876/2458878] Barycentric Julian Datedtime.epochdoubleNFlux[0.96/1.02] Normalized flux in Filterphot.flux;instr.filterdoublee_NFlux[0.0005/0.007] Uncertainty in NFluxstat.errordouble