Two warm Neptunes transiting HIP 9618 revealed by TESS and Cheops
Artikel i vetenskaplig tidskrift, 2023

HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R (HIP 9618 b) and 3.343 ± 0.039 R (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a 680-d gap in the time series, leaving many possibilities for the period. To solve this issue, CHEOPS performed targeted photometry of period aliases to attempt to recover the true period of planet c, and successfully determined the true period to be 52.56349 d. High-resolution spectroscopy with HARPS-N, SOPHIE, and CAFE revealed a mass of 10.0 ± 3.1M for HIP 9618 b, which, according to our interior structure models, corresponds to a 6.8 ± 1.4 per cent gas fraction. HIP 9618 c appears to have a lower mass than HIP 9618 b, with a 3-sigma upper limit of <18M. Follow-up and archival RV measurements also reveal a clear long-term trend which, when combined with imaging and astrometric information, reveal a low-mass companion (0.08+−000512M☉) orbiting at 26.0+−111900 au. This detection makes HIP 9618 one of only five bright (K < 8 mag) transiting multiplanet systems known to host a planet with P > 50 d, opening the door for the atmospheric characterization of warm (Teq < 750 K) sub-Neptunes.

occultations

eclipses

binaries: spectroscopic

planets and satellites: detection

surveys

Författare

H. P. Osborn

Massachusetts Institute of Technology (MIT)

Universität Bern

G. Nowak

Universidad de la Laguna

Instituto de Astrofísica de Canarias

Uniwersytet Mikolaja Kopernika

G. Hebrard

Institut d 'Astrophysique de Paris

T. Masseron

Instituto de Astrofísica de Canarias

Universidad de la Laguna

J. Lillo-Box

European Space Astronomy Centre (ESAC)

E. Palle

Universidad de la Laguna

Instituto de Astrofísica de Canarias

A. Bekkelien

Université de Genève

H.-G. Florén

Stockholms universitet

P. Guterman

Laboratoire d'Astrophysique de Marseille

A.E. Simon

Universität Bern

V. Adibekyan

Universidade do Porto

Allyson Bieryla

Harvard-Smithsonian Center for Astrophysics

L. Borsato

Istituto nazionale di astrofisica (INAF)

A. Brandeker

Stockholms universitet

D. R. Ciardi

National Aeronautics and Space Administration (NASA)

A. Collier Cameron

University of St Andrews

K. A. Collins

Harvard-Smithsonian Center for Astrophysics

J. A. Egger

Universität Bern

D. Gandolfi

Universita degli Studi di Torino

M.J. Hooton

University of Cambridge

Universität Bern

D. W. Latham

Harvard-Smithsonian Center for Astrophysics

M. Lendl

Université de Genève

E. C. Matthews

Max-Planck-Gesellschaft

Université de Genève

A. Tuson

University of Cambridge

S. Ulmer-Moll

Université de Genève

A. Vanderburg

Massachusetts Institute of Technology (MIT)

T.G. Wilson

University of St Andrews

C. Ziegler

Stephen F. Austin State University

Y. Alibert

Universität Bern

R. Alonso

Universidad de la Laguna

Instituto de Astrofísica de Canarias

G. Anglada

Institut d'Estudis Espacials de Catalunya (IEEC)

Institut de Ciències de l'Espai (ICE) - CSIC

L. Arnold

Centre national de la recherche scientifique (CNRS)

J. Asquier

European Space Research and Technology Centre (ESA ESTEC)

D. Barrado Y Navascues

Centro de Astrobiologia (CAB)

W. Baumjohann

Institut fur Weltraumforschung

T. Beck

Universität Bern

A. A. Belinski

Moscow State University

W. Benz

Universität Bern

F. Biondi

Max Planck Institute for Extraterrestrial Physics

Istituto nazionale di astrofisica (INAF)

I. Boisse

Laboratoire d'Astrophysique de Marseille

X. Bonfils

Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)

C. Broeg

Universität Bern

L. A. Buchhave

Danmarks Tekniske Universitet (DTU)

T. Bárczy

Admatis

S.C.C. Barros

Universidade do Porto

J. Cabrera

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

C. Cardona Guillen

Instituto de Astrofísica de Canarias

Universidad de la Laguna

Ilaria Carleo

Instituto de Astrofísica de Canarias

Universidad de la Laguna

A. Castro-González

European Space Astronomy Centre (ESAC)

S. Charnoz

Institut de Physique du Globe de Paris

Jessie L. Christiansen

National Aeronautics and Space Administration (NASA)

Pía Cortés-Zuleta

Laboratoire d'Astrophysique de Marseille

Szilard Csizmadia

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

S. Dalal

Institut d 'Astrophysique de Paris

M. B. Davies

Lunds universitet

M. Deleuil

Laboratoire d'Astrophysique de Marseille

X. Delfosse

Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)

L. Delrez

Universite de Liège

B.O. Demory

Universität Bern

A. B. Dunlavey

National Aeronautics and Space Administration (NASA)

D. Ehrenreich

Université de Genève

Anders Erikson

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

R. B. Fernandes

University of Arizona

A. Fortier

Universität Bern

T. Forveille

Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)

L. Fossati

Institut fur Weltraumforschung

Malcolm Fridlund

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Universiteit Leiden

Michaël Gillon

Universite de Liège

Robert Goeke

Massachusetts Institute of Technology (MIT)

M. V. Goliguzova

Moscow State University

E. Gonzales

University of California

Maximilian N. Günther

European Space Research and Technology Centre (ESA ESTEC)

M. Gudel

Universität Wien

N. Heidari

Laboratoire d'Astrophysique de Marseille

C. E. Henze

NASA Ames Research Center

S. B. Howell

NASA Ames Research Center

S. Hoyer

Laboratoire d'Astrophysique de Marseille

J. I. Frey

Universität Bern

K. Isaak

European Space Research and Technology Centre (ESA ESTEC)

Jon M. Jenkins

NASA Ames Research Center

F. Kiefer

Institut d 'Astrophysique de Paris

Observatoire de Paris

L.L. Kiss

Eötvös Loránd University (ELTE)

Magyar Tudomanyos Akademia

Judith Korth

Lunds universitet

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

P. Maxted

Keele University

J. Laskar

Observatoire de Paris

A. L. des Etangs

Institut d 'Astrophysique de Paris

C. Lovis

Université de Genève

M. B. Lund

National Aeronautics and Space Administration (NASA)

R. Luque

University of Chicago

D. Magrin

Istituto nazionale di astrofisica (INAF)

J. M. Almenara

Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)

E. Martioli

Institut d 'Astrophysique de Paris

Laboratorio Nacional de Astrofisica, Itajuba

M. Mecina

Universität Wien

J. V. Medina

Space Telescope Science Institute (STScI)

D. Moldovan

Google Inc.

M. Morales-Calderon

European Space Astronomy Centre (ESAC)

Giuseppe Morello

Instituto de Astrofísica de Canarias

Universidad de la Laguna

C. Moutou

Institut de Recherche en Astrophysique et Planétologie (IRAP)

F. Murgas

Universidad de la Laguna

Instituto de Astrofísica de Canarias

Eric L.N. Jensen

Swarthmore College

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 523 2 3069-3089

Satellitstudier av exoplaneters mångfald

Rymdstyrelsen (174/18), 2019-02-04 -- 2023-08-01.

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1093/mnras/stad1319

Mer information

Senast uppdaterat

2023-09-15