J/AJ/160/3ivo://CDS.VizieR/J/AJ/160/3doi:10.26093/cds/vizier.51600003CDSCloutier R.Eastman J.D.Rodriguez J.E.Astudillo-Defru N.Bonfils X.,Mortier A.Watson C.A.Stalport M.Pinamonti M.Lienhard F.,Harutyunyan A.Damasso M.Latham D.W.Collins K.A.Massey R.Irwin J.,Winters J.G.Charbonneau D.Ziegler C.Matthews E.Crossfield I.J.M.,Kreidberg L.Quinn S.N.Ricker G.Vanderspek R.Seager S.Winn J.,Jenkins J.M.Vezie M.Udry S.Twicken J.D.Tenenbaum P.Sozzetti A.,Segransan D.Schlieder J.E.Sasselov D.Santos N.C.Rice K.,Rackham B.V.Poretti E.Piotto G.Phillips D.Pepe F.Molinari E.,Mignon L.Micela G.Melo C.de Medeiros J.R.Mayor M.Matson R.A.,Martinez Fiorenzano A.F.Mann A.W.Magazzu A.Lovis C.Lopez-Morales M.,Lopez E.Lissauer J.J.Lepine S.Law N.Kielkopf J.F.Johnson J.A.,Jensen E.L.N.Howell S.B.Gonzales E.Ghedina A.Forveille T.,Figueira P.Dumusque X.Dressing C.D.Doyon R.Diaz R.F.DiFabrizio L.Delfosse X.Cosentino R.Conti D.M.Collins K.I.,Cameron A.C.Ciardi D.Caldwell D.A.Burke C.Buchhave L.Briceno C.,Boyd P.Bouchy F.Beichman C.Artigau E.Almenara J.M.2021-09-13T15:03:04Z2020-10-14T09:56:54ZCDS support team

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

cds-question@unistra.frexoplanetsm-starsdwarf-starsvisible-astronomyspectroscopyradial-velocityWe present the confirmation of two new planets transiting the nearby mid-M dwarf LTT3780 (TIC36724087, TOI-732, V=13.07, Ks=8.204, Rs=0.374R{sun}, Ms=0.401 M{sun}, d=22pc). The two planet candidates are identified in a single Transiting Exoplanet Survey Satellite sector and validated with reconnaissance spectroscopy, ground-based photometric follow-up, and high-resolution imaging. With measured orbital periods of P_b_=0.77, P_c_=12.25days and sizes r_p,b_=1.33{+/-}0.07, r_p,c_=2.30{+/-}0.16R{earth}, the two planets span the radius valley in period-radius space around low-mass stars, thus making the system a laboratory to test competing theories of the emergence of the radius valley in that stellar mass regime. By combining 63 precise radial velocity measurements from the High Accuracy Radial velocity Planet Searcher (HARPS) and HARPS-N, we measure planet masses of m_p,b_=2.62_-0.46_^+0.48^ and m_p,c_=8.6_-1.3_^+1.6^M{earth}, which indicates that LTT3780b has a bulk composition consistent with being Earth-like, while LTT3780c likely hosts an extended H/He envelope. We show that the recovered planetary masses are consistent with predictions from both photoevaporation and core-powered mass-loss models. The brightness and small size of LTT3780, along with the measured planetary parameters, render LTT3780b and c as accessible targets for atmospheric characterization of planets within the same planetary system and spanning the radius valley.2020AJ....160....3Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/3CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/328 : AllWISE Data Release (Cutri+ 2013)I/345 : Gaia DR2 (Gaia Collaboration, 2018)IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)J/AJ/123/2822 : Photometry of southern NLTT stars (Reid+, 2002)J/A+A/442/211 : Spectroscopic distances of 322 NLTT stars (Scholz+, 2005)J/A+A/468/1115 : Thorium and argon lines in the visible (Lovis+, 2007)J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)J/ApJS/200/15 : HARPS-TERRA project. I. (Anglada-Escude+, 2012)J/ApJ/796/127 : Spitzer h and {chi} Persei candidate members (Cloutier+, 2014)J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)J/ApJ/807/45 : Habitable planets orbiting M dwarfs (Dressing+, 2015)J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)J/ApJ/809/25 : Stellar and planet properties for K2 candidates (Montet+,2015)J/AJ/152/141 : Solar neighborhood. XXXVII. RVs for M dwarfs (Benedict+, 2016)J/A+A/600/A13 : HARPS M dwarf sample magnetic activity (Astudillo-Defru+,2017)J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+, 2017)J/AJ/154/109 : California-Kepler Survey . III. Planet radii (Fulton+, 2017)J/A+A/618/A142 : Radial velocity for GJ 1132 (Bonfils+, 2018)J/A+A/615/A69 : K2-3 system characterized with HARPS-N & HARPS (Damasso+,2018)J/AJ/155/136 : Planets orbiting bright stars K2 campaigns 0-10 (Mayo+, 2018)J/AJ/155/180 : A catalog of cool dwarf targets for the TESS (Muirhead+, 2018)J/AJ/156/102 : The TESS Input Catalog & Candidate Target List (Stassun+,2018)J/AJ/157/43 : WASP-161b, WASP-163b and WASP-170b (Barkaoui+, 2019)J/A+A/629/A111 : L 98-59 (TOI 175) HARPS observations (Cloutier+, 2019)J/A+A/621/A49 : K2-18 HARPS time-series (Cloutier+, 2019)J/A+A/627/A43 : Two super-Earths orbiting TOI-402 (Dumusque+, 2019)J/AJ/158/75 : Mid-type M dwarfs planet occur. rates (Hardegree-Ullman+,2019)J/A+A/623/A114 : Light curve of K2-292 (HD 119130) (Luque+, 2019)J/A+A/636/A58 : L 168-9 radial velocity curve (Astudillo-Defru+, 2020)J/AJ/159/211 : Exoplanets parameters from Kepler and K2 (Cloutier+, 2020)J/ApJS/247/28 : K2 star parameters from Gaia & LAMOST (Hardegree-Ullman+,2020)J/AJ/159/19 : SOAR TESS survey. I. (Ziegler+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/3https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/160/3http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/160/3https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/160/3https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/160/3http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/160/3GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/160/3/table2Radial velocity time series of LTT 3780 from HARPS & HARPS-NrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[1656/1924] Baricentric Julian Date; BJD-2457000dtime.epochdoubleRVel[-10.1/10.6] Radial Velocitym/sphys.veloc;pos.heliocentricfloate_RVel[0.79/2.5] Uncertainty in RVelm/sstat.error;spect.dopplerVelocfloatInstInstrument HARPS (33 occurrences) or HARPS-N (30 occurrences)instrchar