J/A+A/620/A142ivo://CDS.VizieR/J/A+A/620/A142doi:10.26093/cds/vizier.36200142CDSAlexoudi X.Mallonn M.von Essen C.Turner J.D.Keles E.,Southworth J.Mancini L.Ciceri S.Granzer T.Denker C.Dineva E.,Strassmeier K.G.2020-01-29T09:10:09Z2018-12-10T08:51:07ZCDS support team

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

cds-question@unistra.frmultiple-starsk-starssolar-system-planetsccd-photometryTwo independent investigations of the atmosphere of the hot Jupiter HAT-P-12b by two different groups resulted in discrepant solutions. Using broad-band photometry from the ground, one study found a flat and featureless transmission spectrum which was interpreted as a gray absorption by dense cloud coverage. The second study made use of the Hubble Space Telescope (HST) observations and found Rayleigh scattering at optical wavelengths caused by haze. The main purpose of this work is to find the source of this inconsistency and provide feedback to prevent similar discrepancies in future analyses of other exoplanetary atmospheres. We studied the observed discrepancy via two methods. With further broad-band observations in the optical wavelength regions, we strengthened the previous measurements in precision and with a homogeneous reanalysis of the published data, we managed to assess the systematic errors and the independent analyses of the two different groups. Repeating the analysis steps of both works, we found that deviating values for the orbital parameters are the reason for the aforementioned discrepancy. Our work showed a degeneracy of the planetary spectral slope with these parameters. In a homogeneous reanalysis of all data, the two literature data sets and the new observations converge to a consistent transmission spectrum, showing a low-amplitude spectral slope and a tentative detection of potassium absorption.2018A&A...620A.142Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/620/A142CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJ/706/785 : HAT-P-12 light curve (Hartman+, 2009)J/AJ/143/95 : Transit light curves of HAT-P-12 (Lee+, 2012)J/AJ/152/88 : Spectroscopy and photometry of HATS-11 & HATS-12 (Rabus+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/620/A142https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/620/A142http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/620/A142https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/620/A142https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/620/A142http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/620/A142GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/620/A142/hatp12bBroadband photometry of HAT-P-12bFWHMWavelength FWHMnminstr.bandwidthfloatTelTelescope name (1)meta.id;instr.telcharTrans[1/10] Transit numbermeta.idintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambdaEffective central wavelength (1)nmem.wl.centralfloatMJDModified, barycentric Julian Date (Julian Date - 2400000.5)dtime.epochdoubleFluxNormalized relative fluxphot.flux;arith.ratiodoublee_FluxUncertainty on relative fluxstat.error;phot.fluxdoubleJ/A+A/620/A142/table1Overview of the new observations of transits of HAT-P-12b during 2016 and 2017recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateObservation datetime.epoch;obsnullableTelTelescopemeta.id;instr.telcharFiltFiltermeta.id;instr.filtercharTexpExposure timestime.duration;obs.exposureintNdataNumber of individual data pointsmeta.numberintrmsScatter of the data points as root-mean-square (rms) of the light curve residualsmagstat.stdev;phot.magfloatbetabeta factorstat.fit.paramfloatMJD1Modified, barycentric Julian Date of first measurementdtime.epochdoubleMJD2Modified, barycentric Julian Date of last measurementdtime.epochdoubleTrans[1/10] Transit numbermeta.idintLCShow the transit light curvemeta.ref.urlchar