J/A+A/711/A86ivo://CDS.VizieR/J/A+A/711/A86CDSRea E.Guenther M.N.Dransfield G.Guillot T.Triaud A.H.M.J.,Stassun K.G.Espinoza-Retamal J.I.Brahm R.Ulmer-Moll S.Beltrame M.,Deloupy V.Timmermans M.Abe L.Agabi K.Bendjoya P.Mekarnia D.,Schmider F.-X.Suarez O.Heras A.M.Lueftinger T.Merin B.Bouchy F.,Henning T.Jordan A.Lendl M.Tala-Pinto M.Trifonov T.Barkaoui K.,Bouma L.G.Boyle G.Briceno .Castro-Gonzalez A.Claringbold A.,Collins K.A.Horne K.Howell S.B.Mann A.W.Murgas F.Palle E.,Quinn S.Rodriguez J.E.Schwarz R.P.Tan T.G.Zhou G.Ziegler C.,Seager S.Winn J.N.2026-07-14T16:25:26Z2026-07-14T17:19:45ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsexoplanetsphotometryradial-velocityvisible-astronomyWe present the analysis of five long-period TESS Objects of Interest (TOIs), each with orbital periods exceeding one month. Initially identified by the Transiting Exoplanet Survey Satellite (TESS), we extensively monitored these targets with the Antarctic Search for Transiting Exoplanets (ASTEP), supported by other facilities in the TESS Follow-Up (TFOP) network. These targets occupy a relatively underexplored region of the period-radius parameter space, offering valuable primordial probes for planetary formation and migration as warm planets better maintain their evolutionary fingerprints. To characterise these systems, we leverage high-resolution speckle imaging to search for nearby stellar companions, and refine stellar parameters using both reconnaissance spectroscopy and spectral energy distribution (SED) fitting. We combine TESS photometry with high- precision ground-based observations from ASTEP, and when available, include additional photometry and radial velocity data. We apply statistical validation to assess the planetary nature of each candidate and use allesfitter to jointly model the photometric and spectroscopic datasets with Markov Chain Monte Carlo (MCMC) sampling to derive robust posterior distributions. With this, we validate the planetary nature of three TOIs, including the two warm Saturns TOI-4507 b (8.2R _{Earth}_, 104d) and TOI-3457 b (10.0R_{Earth}_, 32.6d), as well as the warm sub-Neptune TOI-707 b (2.4R_{Earth}_, 52.8d). The remaining two candidates are identified as eclipsing binaries, namely TOI-2404 and TOI-4404. These results help populate the sparse regime of warm planets, which serve as key tracers of planetary evolution, and demonstrate ASTEP's effectiveness as a ground-based follow-up instrument for long-period systems.2026A&A...711A..86Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/711/A86CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/711/A86https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/711/A86http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/711/A86https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/711/A86https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/711/A86http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/711/A86GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/711/A86/stars (List of studied stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/711/A86/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/711/A86/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/711/A86/stars?GETtext/xml+votable180.050000true98.72975-67.53722220.0055555555555555566/33096 37390 37518 37770 41122https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/711/A86?format=asciiOpticaldefaultJ/A+A/711/A86/starsList of studied starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharRAJ2000Simbad right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Simbad declination (J2000)pos.eq.dec;meta.mainPhotIndicates photometric data in phot.dat filemeta.codecharRVIndicates radial velocity data in rv.dat filemeta.codecharJ/A+A/711/A86/stelparStellar parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintParamParametermeta.notechartoi4507_01Value with error for toi4507_01stat.fit.paramchartoi2404_02_03Value with error for toi2404_02_03stat.fit.paramchartoi707_01Value with error for toi707_01stat.fit.paramchartoi4404_01Value with error for toi4404_01stat.fit.paramchartoi3457_01Value with error for toi3457_01stat.fit.paramcharJ/A+A/711/A86/compparCompanion posterior and derived parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintParamParametermeta.notechartoi4507_01Value with error for toi4507_01stat.fit.paramchartoi2404_02_03Value with error for toi2404_02_03stat.fit.paramchartoi707_01Value with error for toi707_01stat.fit.paramchartoi4404_01Value with error for toi4404_01stat.fit.paramchartoi3457_01Value with error for toi3457_01stat.fit.paramcharJ/A+A/711/A86/addparamAdditional fitted model parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintParamParametermeta.notechartoi4507_01Value with error for toi4507_01stat.fit.paramchartoi2404_02_03Value with error for toi2404_02_03stat.fit.paramchartoi707_01Value with error for toi707_01stat.fit.paramchartoi4404_01Value with error for toi4404_01stat.fit.paramchartoi3457_01Value with error for toi3457_01stat.fit.paramcharJ/A+A/711/A86/priorsPriors adopted in the fitsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintParamParametermeta.notechartoi4507_01Value with error for toi4507_01stat.fit.paramchartoi2404_02_03Value with error for toi2404_02_03stat.fit.paramchartoi707_01Value with error for toi707_01stat.fit.paramchartoi4404_01Value with error for toi4404_01stat.fit.paramchartoi3457_01Value with error for toi3457_01stat.fit.paramcharJ/A+A/711/A86/rvRadial velocity measurements for toi2404, toi3457 and toi4507RVRadial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVRadial velocity uncertaintykm/sstat.errordoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharInstInstrumentmeta.id;instrchartimeBarycentric Julian date (TDB)dtime.epochdoubleJ/A+A/711/A86/photPhotometric time series for toi707, toi2404, toi3457, toi4404 and toi4507recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharInstInstrument with informationsinstrcharTimeBarycentric Julian date (TDB)dtime.epochdoubleindexedFluxNormalized relative fluxphot.flux;arith.ratiodoublee_FluxNormalized relative flux uncertaintystat.error;phot.fluxdouble