Hot planets around cool stars - two short-period mini-Neptunes transiting the late K-dwarf TOI-1260
Journal article, 2021

We present the discovery and characterization of two sub-Neptunes in close orbits, as well as a tentative outer planet of a similar size, orbiting TOI-1260 - a low metallicity K6V dwarf star. Photometry from Transiting Exoplanet Survey Satellite(TESS) yields radii of R-b = 2.33 +/- 0.10 and R-c = 2.82 +/- 0.15 R-circle plus, and periods of 3.13 and 7.49 d for TOI-1260b and TOI-1260c, respectively. We combined the TESS data with a series of ground-based follow-up observations to characterize the planetary system. From HARPS-N high-precision radial velocities we obtain M-b = and M-c = M-circle plus. The star is moderately active with a complex activity pattern, which necessitated the use of Gaussian process regression for both the light-curve detrending and the radial velocity modelling, in the latter case guided by suitable activity indicators. We successfully disentangle the stellar-induced signal from the planetary signals, underlining the importance and usefulness of the Gaussian process approach. We test the system's stability against atmospheric photoevaporation and find that the TOI-1260 planets are classic examples of the structure and composition ambiguity typical for the 2-3 R-circle plus range.

planetary systems

planets and satellites: individual: TOI-1260b, c

stars: low-mass

techniques: radial velocities

planets and satellites: composition

techniques: photometric

planets and satellites: atmospheres

Author

Iskra Georgieva

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

O. Barragan

University of Oxford

G. Nowak

University of La Laguna

Instituto de Astrofísica de Canarias

Malcolm Fridlund

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

D. Locci

Istituto nazionale di astrofisica (INAF)

E. Palle

University of La Laguna

Instituto de Astrofísica de Canarias

R. Luque

University of La Laguna

Instituto de Astrofísica de Canarias

I Carleo

Wesleyan University

D. Gandolfi

University of Turin

S. R. Kane

University of California at Riverside

Judith Korth

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

K. G. Stassun

Vanderbilt University

J.H. Livingston

University of Tokyo

E. C. Matthews

University of Geneva

Massachusetts Institute of Technology (MIT)

K. A. Collins

Harvard-Smithsonian Center for Astrophysics

S. B. Howell

NASA Ames Research Center

L. M. Serrano

University of Turin

S. Albrecht

Aarhus University

Nordic Optical Telescope

A. Bieryla

Harvard-Smithsonian Center for Astrophysics

C. E. Brasseur

Space Telescope Science Institute (STScI)

D. Ciardi

California Institute of Technology (Caltech)

W. D. Cochran

The University of Texas at Austin

K. D. Colon

NASA Goddard Space Flight Center

I. J. M. Crossfield

University of Kansas

Sz Csizmadia

German Aerospace Center (DLR)

H. J. Deeg

Instituto de Astrofísica de Canarias

University of La Laguna

M. Esposito

Thüringer Landessternwarte Tautenburg

E. Furlan

California Institute of Technology (Caltech)

T. Gan

Tsinghua University

E. Goffo

University of Turin

E. Gonzales

University of California at Santa Cruz

S. Grziwa

University of Cologne

E. W. Guenther

Thüringer Landessternwarte Tautenburg

P. Guerra

Albanyà Astronomical Observatory

T. Hirano

National Institutes of Natural Sciences

J. M. Jenkins

NASA Ames Research Center

E. L. N. Jensen

Swarthmore College

P. Kabath

Czech Academy of Sciences

E. Knudstrup

Aarhus University

Nordic Optical Telescope

K. W. F. Lam

Technische Universität Berlin

D. W. Latham

Harvard-Smithsonian Center for Astrophysics

R. A. Matson

US Naval Observatory

H. L. M. Osborne

University College London (UCL)

S. McDermott

Protologic LLC

M. Paegert

Harvard-Smithsonian Center for Astrophysics

S. N. Quinn

Harvard-Smithsonian Center for Astrophysics

S. Redfield

Wesleyan University

G. R. Ricker

Massachusetts Institute of Technology (MIT)

J. E. Schlieder

NASA Goddard Space Flight Center

N. J. Scott

NASA Ames Research Center

S. Seager

Massachusetts Institute of Technology (MIT)

A. M. S. Smith

German Aerospace Center (DLR)

P. Tenenbaum

NASA Ames Research Center

SETI Institute

J. D. Twicken

SETI Institute

NASA Ames Research Center

R. Vanderspek

Massachusetts Institute of Technology (MIT)

V. Van Eylen

University College London (UCL)

J. N. Winn

Princeton University

Monthly Notices of the Royal Astronomical Society

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

Vol. 505 4 4684-4701

Exoplanets from space -CHEOPS and PLATO ESA's next two projects (Phase 2)

Swedish National Space Board (177/19), 2020-01-01 -- 2022-12-31.

Swedish National Space Board (65/19), 2020-01-01 -- 2022-12-31.

Exoplanet diversity with satellite studies

Swedish National Space Board (174/18), 2019-02-04 -- 2023-08-01.

Subject Categories

Astronomy, Astrophysics and Cosmology

Other Chemistry Topics

Probability Theory and Statistics

DOI

10.1093/mnras/stab1464

More information

Latest update

9/15/2023