J/AJ/164/81ivo://CDS.VizieR/J/AJ/164/81doi:10.26093/cds/vizier.51640081CDSKanodia S.Libby-Roberts J.Canas C.I.Ninan J.P.Mahadevan S.,Stefansson G.Lin A.S.J.Jones S.Monson A.Parker B.A.,Kobulnicky H.A.Swaby T.N.Powers L.Beard C.Bender C.F.Blake C.H.,Cochran W.D.Dong J.Diddams S.A.Fredrick C.Gupta A.F.Halverson S.,Hearty F.Logsdon S.E.Metcalf A.J.McElwain M.W.Morley C.,Rajagopal J.Ramsey L.W.Robertson P.Roy A.Schwab C.Terrien R.C.,Wisniewski J.Wright J.T.2023-01-10T08:19:15Z2022-11-21T06:51:38ZCDS support team

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

cds-question@unistra.frexoplanetsm-starsinfrared-astronomyspectroscopyphotometryradial-velocityWe present the discovery of a new Jovian-sized planet, TOI-3757b, the lowest-density transiting planet known to orbit an M dwarf (M0V). This planet was discovered around a solar-metallicity M dwarf, using Transiting Exoplanet Survey Satellite photometry and confirmed with precise radial velocities from the Habitable-zone Planet Finder (HPF) and NEID. With a planetary radius of 12.0_-0.5_^+0.4^R{Earth} and mass of 85.3_-8.7_^+8.8^M{Earth}, not only does this object add to the small sample of gas giants (~10) around M dwarfs, but also its low density ({rho}=0.27_-0.04_^+0.05^g/cm^3^) provides an opportunity to test theories of planet formation. We present two hypotheses to explain its low density; first, we posit that the low metallicity of its stellar host (~0.3dex lower than the median metallicity of M dwarfs hosting gas giants) could have played a role in the delayed formation of a solid core massive enough to initiate runaway accretion. Second, using the eccentricity estimate of 0.14{+/-}0.06, we determine it is also plausible for tidal heating to at least partially be responsible for inflating the radius of TOI-3757b. The low density and large scale height of TOI-3757b makes it an excellent target for transmission spectroscopy studies of atmospheric escape and composition (transmission spectroscopy measurement of ~190). We use HPF to perform transmission spectroscopy of TOI-3757b using the helium 10830{AA} line. Doing this, we place an upper limit of 6.9% (with 90% confidence) on the maximum depth of the absorption from the metastable transition of He at ~10830{AA}, which can help constraint the atmospheric mass-loss rate in this energy-limited regime.2022AJ....164...81Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/164/81CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)J/ApJ/720/1290 : Abundances of stars hosting planets (Ghezzi+, 2010)J/ApJ/726/52 : HAT-P-18 and HAT-P-19 follow-up (Hartman+, 2011)J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)J/A+A/533/A141 : Stellar parameters for 582 HARPS FGK stars (Sousa+, 2011)J/ApJS/200/15 : HARPS-TERRA project. I. (Anglada-Escude+, 2012)J/ApJ/771/129 : Submillimetric Class II sources of Taurus (Andrews+, 2013)J/A+A/562/A71 : Chemical abundances solar neighbourhood dwarfs (Bensby+, 2014)J/ApJ/791/10 : Rad distribution of planets around cool stars (Morton+, 2014)J/AJ/149/166 : Photometry and spectroscopy of HATS-6 (Hartman+, 2015)J/ApJ/831/64 : Mass-metallicity relation for giant planets (Thorngren+, 2016)J/ApJ/825/19 : Mass-radius relationship planets with Rp<4 (Wolfgang+, 2016)J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+, 2017)J/ApJ/836/77 : Library of high-S/N optical spectra of FGKM stars (Yee+, 2017)J/ApJ/856/23 : BANYAN. XI. The BANYAN {Sigma} algorithm (Gagne+, 2018)J/AJ/156/102 : TESS Input Catalog and Candidate Target List (Stassun+, 2018)J/A+A/623/A72 : Binarity of Hipparcos stars, Gaia pm anomaly (Kervella+, 2019)J/A+A/624/A94 : The role of the host star's metallicity (Maldonado+, 2019)J/AJ/160/201 : Infrared transmission spectrum for Kepler-79d (Chachan+, 2020)J/A+A/644/A127 : LP714-47 (TOI 442) radial velocity curve (Dreizler+, 2020)J/ApJ/899/29 : Radial velocities of TOI-1728 with HPF (Kanodia+, 2020)J/AJ/159/100 : Flux & RVs of dwarf G9-40 with K2 & HPF (Stefansson+, 2020)J/AJ/163/125 : Light curve & radial velocity 4 giants planets (Jordan+, 2022)J/ApJS/259/33 : Faint-star TOIs from TESS Primary Mission (Kunimoto+, 2022)J/A+A/658/A194 : Stellar parameters of 18 M dwarfs (Passegger+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/164/81https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/164/81http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/164/81https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/164/81https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/164/81http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/164/81GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/164/81/table1Radial velocities (binned in ~30minute exposures) of TOI-3757recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2459458/2459590] Barycentric Julian Date; TDBdtime.epochdoubleRVel[-140/67] Radial velocitym/sphys.veloc;pos.heliocentricfloate_RVel[6/29] Uncertainty in RVelm/sstat.error;spect.dopplerVelocfloatInstInstrument; HPF or NEIDmeta.id;instrcharJ/AJ/164/81/fig6Ground based observations for TOI-3757b from RBOrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2459536/2459537] Barycentric Julian Date; TDBdtime.epochdoubleFlux[0.01/0.03] Relative fluxphot.flux;arith.ratiodoublee_Flux[5e-5/6e-5] Uncertainty in Fluxstat.error;phot.fluxfloat