The Discovery and Follow-up of Four Transiting Short-period Sub-Neptunes Orbiting M Dwarfs
Artikel i vetenskaplig tidskrift, 2024

Sub-Neptunes with radii of 2-3 R ⊕ are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes provide clues to the formation and evolution of close-in small planets. In this paper, we present the discovery and follow-up of four sub-Neptunes orbiting M dwarfs (TOI-782, TOI-1448, TOI-2120, and TOI-2406), three of which were newly validated by ground-based follow-up observations and statistical analyses. TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b have radii of R p = 2.740 − 0.079 + 0.082 R ⊕ , 2.769 − 0.068 + 0.073 R ⊕ , 2.120 ± 0.067 R ⊕, and 2.830 − 0.066 + 0.068 R ⊕ and orbital periods of P = 8.02, 8.11, 5.80, and 3.08 days, respectively. Doppler monitoring with the Subaru/InfraRed Doppler instrument led to 2σ upper limits on the masses of <19.1 M ⊕, <19.5 M ⊕, <6.8 M ⊕, and <15.6 M ⊕ for TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b, respectively. The mass-radius relationship of these four sub-Neptunes testifies to the existence of volatile material in their interiors. These four sub-Neptunes, which are located above the so-called “radius valley,” are likely to retain a significant atmosphere and/or an icy mantle on the core, such as a water world. We find that at least three of the four sub-Neptunes (TOI-782 b, TOI-2120 b, and TOI-2406 b), orbiting M dwarfs older than 1 Gyr, are likely to have eccentricities of e ∼ 0.2-0.3. The fact that tidal circularization of their orbits is not achieved over 1 Gyr suggests inefficient tidal dissipation in their interiors.

Författare

Yasunori Hori

National Institutes of Natural Sciences

A. Fukui

University of Tokyo

T. Hirano

National Institutes of Natural Sciences

Norio Narita

National Institutes of Natural Sciences

Jerome P. De Leon

University of Tokyo

Hiroyuki Tako Ishikawa

Western University

Joel D. Hartman

Princeton University

Giuseppe Morello

Instituto de Astrofísica de Canarias

N. Abreu Garcia

Instituto de Astrofísica de Canarias

Leticia Álvarez Hernández

Instituto de Astrofísica de Canarias

V. J. S. Bejar

Instituto de Astrofísica de Canarias

Yéssica Calatayud-Borras

Instituto de Astrofísica de Canarias

Ilaria Carleo

Instituto de Astrofísica de Canarias

Gareb Enoc

Instituto de Astrofísica de Canarias

E. Esparza-Borges

Instituto de Astrofísica de Canarias

Izuru Fukuda

University of Tokyo

D. Galán

Instituto de Astrofísica de Canarias

S. Geraldía-González

Instituto de Astrofísica de Canarias

Y. Hayashi

University of Tokyo

Masahiro Ikoma

National Astronomical Observatory of Japan

Kai Ikuta

University of Tokyo

Keisuke Isogai

University of Tokyo

T. Kagetani

University of Tokyo

Yugo Kawai

University of Tokyo

Kiyoe Kawauchi

College of Life Sciences

Tadahiro Kimura

National Astronomical Observatory of Japan

T. Kodama

Tokyo Institute of Technology

Judith Korth

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

Nobuhiko Kusakabe

National Institutes of Natural Sciences

A. Laza-Ramos

Universitat de Valencia

J.H. Livingston

National Institutes of Natural Sciences

R. Luque

University of Chicago

Kohei Miyakawa

National Astronomical Observatory of Japan

Mayuko Mori

National Institutes of Natural Sciences

F. Murgas

Instituto de Astrofísica de Canarias

J. Orell-Miquel

Instituto de Astrofísica de Canarias

Enric Palle

Instituto de Astrofísica de Canarias

H. Parviainen

Instituto de Astrofísica de Canarias

A. Peláez-Torres

Instituto de Astrofísica de Canarias

M. Puig-Subirà

Instituto de Astrofísica de Canarias

M. Sánchez-Benavente

Instituto de Astrofísica de Canarias

Paula Sosa-Guillén

Instituto de Astrofísica de Canarias

M. Stangret

Istituto nazionale di astrofisica (INAF)

Y. Terada

Academia Sinica

Sara Muñoz Torres

Instituto de Astrofísica de Canarias

Noriharu Watanabe

University of Tokyo

Gaspar Á. Bakos

Princeton University

Khalid Barkaoui

Instituto de Astrofísica de Canarias

C. Beichman

National Aeronautics and Space Administration (NASA)

Z. Benkhaldoun

Faculté des Sciences Semlalia

A. W. Boyle

California Institute of Technology (Caltech)

D. R. Ciardi

California Institute of Technology (Caltech)

Catherine A. Clark

National Aeronautics and Space Administration (NASA)

Karen A. Collins

Harvard-Smithsonian Center for Astrophysics

Kevin I. Collins

George Mason University

D. Conti

American Association of Variable Star Observers

I. J.M. Crossfield

University of Kansas

M.E. Everett

NSF's National Optical-Infrared Astronomy Research Laboratory (NOIRLab)

Elise Furlan

National Aeronautics and Space Administration (NASA)

M. Ghachoui

Universite de Liège

Michaël Gillon

Universite de Liège

Erica J. Gonzales

University of California at Santa Cruz

Jesus Higuera

NSF's National Optical-Infrared Astronomy Research Laboratory (NOIRLab)

Keith Horne

SUPA

S.B. Howell

NASA Ames Research Center

Emmanuel Jehin

Universite de Liège

Kathryn V. Lester

NASA Ames Research Center

M. B. Lund

National Aeronautics and Space Administration (NASA)

Rachel A. Matson

US Naval Observatory

Elisabeth Matthews

Max-Planck-Institut für Astronomie

Francisco J. Pozuelos

Instituto de Astrofisica de Andalucía (IAA)

B. S. Safonov

Moscow State University

Joshua E. Schlieder

NASA Goddard Space Flight Center

R. Schwarz

Harvard-Smithsonian Center for Astrophysics

Ramotholo Sefako

South African Astronomical Observatory

G. Srdoc

Kotizarovci Observatory

I. A. Strakhov

Moscow State University

M. Timmermans

Universite de Liège

William C. Waalkes

University of Colorado at Boulder

C. Ziegler

Stephen F. Austin State University

D. Charbonneau

Harvard-Smithsonian Center for Astrophysics

Zahra Essack

University of New Mexico

N. Guerrero

Massachusetts Institute of Technology (MIT)

University of Florida

Hiroki Harakawa

National Astronomical Observatory of Japan

Christina Hedges

NASA Goddard Space Flight Center

Masato Ishizuka

University of Tokyo

Jon M. Jenkins

NASA Ames Research Center

Mihoko Konishi

Oita University

Takayuki Kotani

National Institutes of Natural Sciences

T. Kudo

National Astronomical Observatory of Japan

Takashi Kurokawa

National Astronomical Observatory of Japan

M. Kuzuhara

National Institutes of Natural Sciences

Jun Nishikawa

National Institutes of Natural Sciences

Masashi Omiya

National Institutes of Natural Sciences

George R. Ricker

Massachusetts Institute of Technology (MIT)

S. Seager

Massachusetts Institute of Technology (MIT)

Takuma Serizawa

National Astronomical Observatory of Japan

S. Striegel

SETI Institute

Motohide Tamura

National Institutes of Natural Sciences

Akitoshi Ueda

National Institutes of Natural Sciences

Roland K. Vanderspek

Massachusetts Institute of Technology (MIT)

Sébastien Vievard

National Astronomical Observatory of Japan

J. N. Winn

Princeton University

Astronomical Journal

0004-6256 (ISSN) 1538-3881 (eISSN)

Vol. 167 6 289

Ämneskategorier

Astronomi, astrofysik och kosmologi

Den kondenserade materiens fysik

DOI

10.3847/1538-3881/ad4115

Mer information

Senast uppdaterat

2024-06-19