J/AJ/168/185ivo://CDS.VizieR/J/AJ/168/185doi:10.26093/cds/vizier/be-58-5sCDSEspinoza-Retamal J.I.Stefansson G.Petrovich C.Brahm R.Jordan A.,Sedaghati E.Lucero J.P.Tala Pinto M.Munoz D.J.Boyle G.Leiva R.,Suc V.2026-07-02T11:44:56Z2025-06-13T09:44:18ZCDS support team

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

cds-question@unistra.frexoplanetsvisible-astronomyspectroscopyphotometryradial-velocityWe constrain the sky-projected obliquities of two low-density hot Neptune planets, HATS-38 b and WASP-139 b, orbiting nearby G and K stars using Rossiter-McLaughlin (RM) observations with VLT/ESPRESSO, yielding {lambda}=-108_-16_^+11^deg and -85.6_-4.2_^+7.7^deg, respectively. To model the RM effect, we use a new publicly available code, ironman, which is capable of jointly fitting transit photometry, Keplerian radial velocities, and RM effects. WASP-139 b has a residual eccentricity e=0.103_-0.041_^+0.050^ while HATS-38 b has an eccentricity of e=0.112_-0.070_^+0.072^, which is compatible with a circular orbit given our data. Using the obliquity constraints, we show that they join a growing group of hot and low-density Neptunes on polar orbits. We use long-term radial velocities to rule out companions with masses ~0.3-50M_J_ within ~10AU. We show that the orbital architectures of the two Neptunes can be explained with high-eccentricity migration from >=2AU driven by an unseen distant companion. If HATS-38 b has no residual eccentricity, its polar and circular orbit can also be consistent with a primordial misalignment. Finally, we perform a hierarchical Bayesian modeling of the true obliquity distribution of Neptunes and find suggestive evidence for a higher preponderance of polar orbits for hot Neptunes compared to Jupiters. However, we note that the exact distribution is sensitive to the choice of priors, highlighting the need for additional obliquity measurements of Neptunes to robustly compare the hot Neptune obliquity distribution to that of Jupiters.2024AJ....168..185Ehttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/168/185CatalogResearchIsServedByTAP VizieR generic servicerelated-toVI/151 : Search for radio emission from giant exoplanets (Griessmeier, 2016)IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)J/ApJ/757/18 : RVs for 16 hot Jupiter host stars (Albrecht+, 2012)J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)J/AJ/148/81 : APASS BVgri photometry of RAVE stars. I.Data (Munari+, 2014)J/MNRAS/465/3693 : 7 WASP-South transiting exoplanets (Hellier+, 2017)J/AJ/155/255 : RVs and activity measurements of HAT-P-11 (Yee+, 2018)J/AJ/158/45 : TESS light curve & RVs for HD 1397 (Brahm+, 2019)J/other/Nat/586.528 : Properties of exoplanet host stars (Winter+, 2020)J/AJ/160/192 : Photometry and RVs of K2-25b with HPF (Stefansson+, 2020)J/AJ/160/222 : RVs and RI-photometry of HATS-37 and HATS-38 (Jordan+, 2020)J/A+A/646/A77 : Chromospheric activity: AMBRE-HARPS (Gomes da Silva+, 2021)J/AJ/161/70 : RVs for WASP-107 with HIRES & CORALIE (Piaulet+, 2021)J/AJ/161/119 : The TESS-Keck survey. IV. RV for WASP-107 (Rubenzahl+, 2021)J/AJ/164/15 : Exoplanets considered as Ariel's targets (Edwards+, 2022)J/ApJ/921/24 : Planetary masses and radii (Schlaufman+, 2021)J/ApJS/259/62 : TESS transit timing of hot Jupiters (Ivshina+, 2022)J/ApJ/931/L15 : Obs. of 2 transits of GJ 3470b with NEID (Stefansson+, 2022)J/AJ/168/116 : NEID RVs of TOI-5126 and TOI-5398 (Radzom+, 2024)J/ApJS/270/14 : Transit times of hot Jupiters from TESS (Wang+, 2024)http://heasarc.gsfc.nasa.gov/docs/tess/ : NASA TESS Science Support Centerhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/168/185https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/168/185http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/168/185https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/168/185https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/168/185http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/168/185GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/168/185/fig1lcLight curves of HATS-38 (Data behind figure 1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2457790/2460500] Barycentric Julian Datedtime.epochdoubleFlux[0.97/1.02] Relative fluxphot.flux;arith.ratiodoublee_Flux[3e-4/3e-3] Uncertainty in fluxstat.error;phot.fluxdoubleInstInstrument used (1)meta.id;instrcharJ/AJ/168/185/fig1rvRadial velocities of HATS-38 (Data behind figure 1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2457708/2460300] Barycentric Julian Datedtime.epochdoubleRVel[-2.2e1/4.2e3] Radial velocitym/sspect.dopplerVelocdoublee_RVel[1.41/15] Uncertainty in radial velocitym/sstat.error;spect.dopplerVelocdoubleInstInstrument used (1)meta.id;instrcharJ/AJ/168/185/fig2lcLight curves of WASP-139 (Data behind figure 2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2456876/2459170] Barycentric Julian Datedtime.epochdoubleFlux[0.97/1.01] Relative fluxphot.flux;arith.ratiodoublee_Flux[7.2e-4/3.3e-3] Uncertainty in relative fluxstat.error;phot.fluxdoubleInstInstrument used (1)meta.id;instrcharJ/AJ/168/185/fig2rvRadial velocities of WASP-139 (Data behind figure 2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJD[2454750/2460281] Barycentric Julian Datedtime.epochdoubleRVel[-1.31e4/-1.29e4] Radial velocitym/sspect.dopplerVelocdoublee_RVel[1.55/41.3] Uncertainty in radial velocitym/sstat.error;spect.dopplerVelocfloatInstInstrument used (1)meta.id;instrchar