K2-290: a warm Jupiter and a mini-Neptune in a triple-star system
Artikel i vetenskaplig tidskrift, 2019

We report the discovery of two transiting planets orbiting K2-290 (EPIC 249624646), a bright (V = 11.11) late F-type star residing in a triple-star system. It was observed during Campaign 15 of the K2 mission, and in order to confirm and characterize the system, follow-up spectroscopy and AO imaging were carried out using the FIES, HARPS, HARPS-N, and IRCS instruments. From AO imaging and Gaia data we identify two M-dwarf companions at a separation of 113 ± 2 and 246-155+177 au. From radial velocities, K2 photometry, and stellar characterization of the host star, we find the inner planet to be a mini-Neptune with a radius of 3.06 ± 0.16 R⊕ and an orbital period of P = 9.2 d. The radius of the mini-Neptune suggests that the planet is located above the radius valley, and with an incident flux of F ~ 400 F⊕, it lies safely outside the super-Earth desert. The outer warm Jupiter has a mass of 0.774 ± 0.047 MJ and a radius of 1.006 ± 0.050 RJ, and orbits the host star every 48.4 d on an orbit with an eccentricity e < 0.241. Its mild eccentricity and mini-Neptune sibling suggest that the warm Jupiter originates from in situ formation or disc migration.

planets and satellites: individual: EPIC 249624646

planets and satellites: detection

planets and satellites: formation

planets and satellites: individual: K2-290

Författare

M. Hjorth

A.B. Justesen

T. Hirano

S. Albrecht

D. Gandolfi

F. Dai

R. Alonso

O. Barragan

M. Esposito

M. Kuzuhara

K.W.F. Lam

J.H. Livingston

P. Montanés Rodríguez

N. Narita

G. Nowak

J. Prieto-Arranz

S. Redfield

F. Rodler

V. Van Eylen

J. N. Winn

G. Antoniciello

J. Cabrera

W. D. Cochran

Sz. Csizmadia

J. P. de Leon

H. Deeg

Ph Eigmüller

M. Endl

A. Erikson

Malcolm Fridlund

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

S. Grziwa

E. Guenther

A. P. Hatzes

P. Heeren

D. Hidalgo

J. Korth

R. Luque

D. Nespral

M. Pätzold

Carina Persson

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

H. Rauer

A. M. S. Smith

T. Trifonov

Monthly Notices of the Royal Astronomical Society

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

Vol. 484 3 3522-3536

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/stz139

Mer information

Skapat

2019-02-19