K2-140b and K2-180b - Characterization of a hot Jupiter and a mini-Neptune from the K2 mission
Artikel i vetenskaplig tidskrift, 2019

We report the independent discovery and characterization of two K2 planets: K2-180b, a mini-Neptune-sized planet in an 8.9-d orbit transiting a V = 12.6 mag, metal-poor ([Fe/H] = -0.65 ± 0.10) K2V star in K2 campaign 5; K2-140b, a transiting hot Jupiter in a 6.6-d orbit around a V = 12.6 mag G6V ([Fe/H] = + 0.10 ± 0.10) star in K2 campaign 10. Our results are based on K2 time-series photometry combined with high-spatial resolution imaging and high-precision radial velocity measurements. We present the first mass measurement of K2-180b. K2-180b has a mass of Mp = 11.3 ± 1.9 M_Earth and a radius of Rp = 2.2 ± 0.1 R_Earth, yielding a mean density of ρp = 5.6 ± 1.9 g cm-3, suggesting a rocky composition. Given its radius, K2-180b is above the region of the so-called `planetary radius gap'. K2-180b is in addition not only one of the densest mini-Neptune-sized planets, but also one of the few mini-Neptune-sized planets known to transit a metal-poor star. We also constrain the planetary and orbital parameters of K2-140b and show that, given the currently available Doppler measurements, the eccentricity is consistent with zero, contrary to the results of a previous study.

planets and satellites: fundamental parameters

stars: individual: K2-180

stars: individual: K2-140

stars: fundamental parameters

techniques: photometric

techniques: radial velocities

Författare

J. Korth

Universität zu Köln

Sz. Csizmadia

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

D. Gandolfi

Universita degli Studi di Torino

Malcolm Fridlund

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

M. Pätzold

Universität zu Köln

T. Hirano

Tokyo Institute of Technology

J. Livingston

Tokyo Institute of Technology

Carina Persson

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

H. J. Deeg

Universidad de la Laguna

A.B. Justesen

Aarhus Universitet

O. Barragan

Universita degli Studi di Torino

S. Grziwa

Universität zu Köln

M. Endl

The University of Texas at Austin

R. Tronsgaard

Nordic Optical Telescope

F. Dai

Massachusetts Institute of Technology (MIT)

W. D. Cochran

The University of Texas at Austin

S. Albrecht

Aarhus Universitet

R. Alonso

Universidad de la Laguna

J. Cabrera

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

P.W. Cauley

Wesleyan University

F. Cusano

Istituto nazionale di astrofisica (INAF)

Ph Eigmüller

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

A. Erikson

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

M. Esposito

Thüringer Landessternwarte Tautenburg

E. W. Guenther

Thüringer Landessternwarte Tautenburg

A. P. Hatzes

Thüringer Landessternwarte Tautenburg

D. Hidalgo

Universidad de la Laguna

M. Kuzuhara

National Institutes of Natural Sciences

P. Montañes

Universidad de la Laguna

N.R. Napolitano

Istituto nazionale di astrofisica (INAF)

N. Narita

National Institutes of Natural Sciences

University of Tokyo

Universidad de la Laguna

P. Niraula

Wesleyan University

D. Nespral

Universidad de la Laguna

G. Nowak

Universidad de la Laguna

E. Palle

Universidad de la Laguna

C.E. Petrillo

Rijksuniversiteit Groningen

S. Redfield

Wesleyan University

J. Prieto-Arranz

Universidad de la Laguna

H. Rauer

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Technische Universität Berlin

Freie Universität Berlin

A. M. S. Smith

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

C. Tortora

Rijksuniversiteit Groningen

V. Van Eylen

Universiteit Leiden

J. N. Winn

Princeton University

Monthly Notices of the Royal Astronomical Society

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

Vol. 482 2 1807-1823

Exoplaneter från rymden - CHEOPS och PLATO

Rymdstyrelsen, 2017-01-01 -- 2022-12-31.

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

DOI

10.1093/mnras/sty2760

Mer information

Senast uppdaterat

2020-05-14