The Transiting Multi-planet System HD 3167: A 5.7 M ⊕ Super-Earth and an 8.3 M ⊕ Mini-Neptune
Artikel i vetenskaplig tidskrift, 2017

HD 3167 is a bright (V = 8.9 mag) K0 V star observed by NASA’s K2 space mission during its Campaign 8. It has recently been found to host two small transiting planets, namely, HD 3167b, an ultra-short-period (0.96 days) super-Earth, and HD 3167c, a mini-Neptune on a relatively long-period orbit (29.85 days). Here we present an intensive radial velocity (RV) follow-up of HD 3167 performed with the FIES@NOT, HARPS@ESO-3.6 m, and HARPS-N@TNG spectrographs. We revise the system parameters and determine radii, masses, and densities of the two transiting planets by combining the K2 photometry with our spectroscopic data. With a mass of 5.69 ± 0.44 M⊕, a radius of 1.574 ± 0.054 R⊕, and a mean density of {8.00}-0.98+1.10 g cm^-3, HD 3167b joins the small group of ultra-short-period planets known to have rocky terrestrial compositions. HD 3167c has a mass of 8.33-1.85+1.79 M⊕ and a radius of 2.74}-0.100+0.106 R⊕, yielding a mean density of 2.21-0.53+0.56 g cm^-3, indicative of a planet with a composition comprising a solid core surrounded by a thick atmospheric envelope. The rather large pressure scale height (∼350 km) and the brightness of the host star make HD 3167c an ideal target for atmospheric characterization via transmission spectroscopy across a broad range of wavelengths. We found evidence of additional signals in the RV measurements but the currently available data set does not allow us to draw any firm conclusions on the origin of the observed variation.

planets and satellites: individual: HD 3167b

stars: fundamental parameters

stars: individual: HD 3167

planets and satellites: detection

HD 3167c

Författare

Davide Gandolfi

Universita degli Studi di Torino

Oscar Barragán

Universita degli Studi di Torino

Artie P. Hatzes

Thüringer Landessternwarte Tautenburg

Malcolm Fridlund

Astronomi och plasmafysik

Luca Fossati

Institut fur Weltraumforschung

Paolo Donati

Osservatorio Astrofisico di Arcetri

Marshall C. Johnson

Ohio State University

Grzegorz Nowak

Instituto Astrofisico de Canarias

Universidad de la Laguna

Jorge Prieto-Arranz

Universidad de la Laguna

Instituto Astrofisico de Canarias

Simon Albrecht

Aarhus Universitet

Fei Dai

Massachusetts Institute of Technology (MIT)

Princeton University

Hans Deeg

Instituto Astrofisico de Canarias

Universidad de la Laguna

Michael Endl

The University of Texas at Austin

Sascha Grziwa

Universität zu Köln

Maria Hjorth

Aarhus Universitet

Judith Korth

Universität zu Köln

David Nespral

Universidad de la Laguna

Instituto Astrofisico de Canarias

Joonas Saario

Nordic Optical Telescope

Alexis M. S. Smith

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Giuliano Antoniciello

Universita degli Studi di Torino

Javier Alarcon

European Southern Observatory Santiago

Megan Bedell

University of Chicago

Pere Blay

Instituto Astrofisico de Canarias

Nordic Optical Telescope

Stefan S. Brems

Landessternwarte Heidelberg

Juan Cabrera

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Szilard Csizmadia

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Felice Cusano

INAF Istituto di Astrofisica Spaziale e Fisica Cosmica, Bologna

William D. Cochran

The University of Texas at Austin

Philipp Eigmüller

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Anders Erikson

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

González Hernández

Universidad de la Laguna

Instituto Astrofisico de Canarias

Eike W. Guenther

Thüringer Landessternwarte Tautenburg

Teruyuki Hirano

Tokyo Institute of Technology

Alejandro Suárez Mascareño

Universite de Geneve

Instituto Astrofisico de Canarias

Norio Narita

University of Tokyo

National Institutes of Natural Sciences

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

Enric Palle

Universidad de la Laguna

Instituto Astrofisico de Canarias

Hannu Parviainen

Instituto Astrofisico de Canarias

Universidad de la Laguna

Martin Pätzold

Universität zu Köln

Carina Persson

Astronomi och plasmafysik

Heike Rauer

Technische Universität Berlin

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Ivo Saviane

European Southern Observatory Santiago

Linda Schmidtobreick

European Southern Observatory Santiago

Vincent Van Eylen

Universiteit Leiden

Joshua N. Winn

Princeton University

Olga V. Zakhozhay

Main Astronomical Observatory Nasu

Astronomical Journal

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

Vol. 154 3 123- 123

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

DOI

10.3847/1538-3881/aa832a