Mass determinations of the three mini-Neptunes transiting TOI-125
Journal article, 2020

The Transiting Exoplanet Survey Satellite, TESS, is currently carrying out an all-sky search for small planets transiting bright stars. In the first year of the TESS survey, a steady progress was made in achieving the mission's primary science goal of establishing bulk densities for 50 planets smaller than Neptune. During that year, the TESS's observations were focused on the southern ecliptic hemisphere, resulting in the discovery of three mini-Neptunes orbiting the star T01-125, a V = 11,0 KO dwarf. We present intensive HARPS radial velocity observations, yielding precise mass measurements for TO1-125b, TOI-125c, and TOI-125d. TOI-125b has an orbital period of 4,65 d, a radius of 2,726 + 0,075 RE, a mass of 9,50 0,88 ME, and is near the 2:1 mean motion resonance with TOI-125c at 9.15 d. TOI-125c has a similar radius of 2,759 0.10 RE and a mass of 6,63 + 0,99 ME, being the puffiest of the three planets. T01-125d has an orbital period of 19,98 d and a radius of 2.93 + 0,17 RE and mass 13,6 1,2 ME, For T01-125b and d, we find unusual high eccentricities of 0.19 0.04 and 0.17+(c):(!,(, respectively. Our analysis also provides upper mass limits for the two low-SNR planet candidates in the system; for T01-125.04 (Rp = 1.36 RE, P = 0.53 d), we find a 2a upper mass limit of 1.6 ME, whereas T01-125.05 (RP = 4.2-'2E44 RE, P = 13.28 d) is unlikely a viable planet candidate with an upper mass limit of 2.7 ME. We discuss the internal structure of the three confirmed planets, as well as dynamical stability and system architecture for this intriguing exoplanet system.

Planets and satellites: detection

Planets and satellites: individual: (TOI-125, TIC 52368076)

Author

L. D. Nielsen

University of Geneva

D. Gandolfi

University of Turin

D. J. Armstrong

The University of Warwick

J. S. Jenkins

University of Chile (UCH)

Malcolm Fridlund

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

N. C. Santos

Universidade do Porto

F. Dai

California Institute of Technology (Caltech)

V Adibekyan

Universidade do Porto

R. Luque

University of La Laguna

Instituto Astrofisico de Canarias

J. H. Steffen

University of Nevada, Las Vegas

M. Esposito

Thüringer Landessternwarte Tautenburg

F. Meru

The University of Warwick

S. Sabotta

Thüringer Landessternwarte Tautenburg

E. Bolmont

University of Geneva

D. Kossakowski

Max Planck Society

J. F. Otegi

University of Zürich

University of Geneva

F. Murgas

University of La Laguna

Instituto Astrofisico de Canarias

M. Stalport

University of Geneva

F. Rodler

European Southern Observatory Santiago

M. R. Diaz

University of Chile (UCH)

N. T. Kurtovic

University of Chile (UCH)

G. Ricker

Massachusetts Institute of Technology (MIT)

R. Vanderspek

Massachusetts Institute of Technology (MIT)

D. W. Latham

Harvard-Smithsonian Center for Astrophysics

S. Seager

Massachusetts Institute of Technology (MIT)

J. N. Winn

Princeton University

J. M. Jenkins

NASA Ames Research Center

R. Allart

University of Geneva

J. M. Almenara

University of Geneva

D. Barrado

Ctr Astrobiol CSIC INTA

S.C.C. Barros

Universidade do Porto

D. Bayliss

The University of Warwick

Z. M. Berdinas

University of Chile (UCH)

I Boisse

Aix Marseille University

F. Bouchy

University of Geneva

P. Boyd

NASA Goddard Space Flight Center

D. J. A. Brown

The University of Warwick

E. M. Bryant

The University of Warwick

C. Burke

Massachusetts Institute of Technology (MIT)

W. D. Cochran

The University of Texas at Austin

B. F. Cooke

The University of Warwick

O. D. S. Demangeon

Universidade do Porto

R. F. Diaz

Universidad de Buenos Aires

J. Dittman

Massachusetts Institute of Technology (MIT)

C. Dorn

Leiden University

X. Dumusque

University of Geneva

R. A. Garcia

University Paris-Saclay

Paris Diderot University

L. Gonzalez-Cuesta

Instituto Astrofisico de Canarias

University of La Laguna

S. Grziwa

University of Cologne

Iskra Georgieva

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

N. Guerrero

Massachusetts Institute of Technology (MIT)

A. P. Hatzes

Thüringer Landessternwarte Tautenburg

R. Helled

Leiden University

C. E. Henze

NASA Ames Research Center

S. Hojjatpanah

Universidade do Porto

J. Korth

University of Cologne

K. W. F. Lam

Technische Universität Berlin

J. Lillo-Box

Ctr Astrobiol CSIC INTA

T. A. Lopez

Aix Marseille University

J. Livingston

University of Tokyo

S. Mathur

Instituto Astrofisico de Canarias

University of La Laguna

O. Mousis

Aix Marseille University

N. Narita

Instituto Astrofisico de Canarias

Ctr Astrobiol CSIC INTA

National Astronomical Observatory of Japan

Japan Science and Technology Agency

H. P. Osborn

University of Bern

Aix Marseille University

E. Palle

Instituto Astrofisico de Canarias

University of La Laguna

P. A. Pena Rojas

University of Chile (UCH)

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics

S. N. Quinn

Harvard-Smithsonian Center for Astrophysics

H. Rauer

Technische Universität Berlin

Freie Universität Berlin

German Aerospace Center (DLR)

S. Redfield

Wesleyan University

A. Santerne

Aix Marseille University

L. A. dos Santos

University of Geneva

Seidel

University of Geneva

S. G. Sousa

Universidade do Porto

E. B. Ting

NASA Ames Research Center

M. Turbet

University of Geneva

S. Udry

University of Geneva

A. Vanderburg

The University of Texas at Austin

V. Van Eylen

University College London (UCL)

Vines

University of Chile (UCH)

P. J. Wheatley

The University of Warwick

P. A. Wilson

The University of Warwick

Monthly Notices of the Royal Astronomical Society

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

Vol. 492 4 5399-5412

Subject Categories

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

DOI

10.1093/mnras/staa197

More information

Latest update

9/24/2020