EPIC 219388192b-An Inhabitant of the Brown Dwarf Desert in the Ruprecht 147 Open Cluster
Artikel i vetenskaplig tidskrift, 2017

We report the discovery of EPIC 219388192b, a transiting brown dwarf in a 5.3 day orbit around a member star of Ruprecht 147, the oldest nearby open cluster association, which was photometrically monitored by K2 during its Campaign 7. We combine the K2 time-series data with ground-based adaptive optics imaging and high-resolution spectroscopy to rule out false positive scenarios and determine the main parameters of the system. EPIC 219388192b has a radius of R-b= 0.937 +/- 0.032 R-Jup and mass of M-b= 36.84 +/- 0.97 M-Jup, yielding a mean density of 59.6 +/- 7.6 g cm(- 3). The host star is nearly a solar twin with mass M-star = 1.01 +/- 0.04 Me, radius R-star = 1.01 +/- 0.03 R-circle dot, effective temperature T-eff = 5850 +/- 85 K, and iron abundance [Fe/ H]. = 0.03 +/- 0.08 dex. Its age, spectroscopic distance, and reddening are consistent with those of Ruprecht 147, corroborating its cluster membership. EPIC 219388192b is the first mature brown dwarf with precise determinations of mass, radius, and age, and serves as benchmark for evolutionary models in the substellar regime.

techniques : photometric

stars : individual (EPIC 219388192)

techniques : radial velocities

techniques : spectroscopic

photometric

brown dwarfs

Författare

G. Nowak

Universidad de la Laguna

Instituto Astrofisico de Canarias

E. Palle

Instituto Astrofisico de Canarias

Universidad de la Laguna

D. Gandolfi

Universita degli Studi di Torino

Landessternwarte Heidelberg

F. Dai

Massachusetts Institute of Technology (MIT)

A. F. Lanza

Osservatorio Astrofisico di Catania

T. Hirano

Tokyo Institute of Technology

O. Barragán

Universita degli Studi di Torino

A. Fukui

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

H. Bruntt

Aarhus Universitet

M. Endl

The University of Texas at Austin

W. D. Cochran

The University of Texas at Austin

P. G. P. Moroni

Universita di Pisa

Istituto Nazionale Di Fisica Nucleare, Frascati

J. Prieto-Arranz

Instituto Astrofisico de Canarias

Universidad de la Laguna

A. Kiilerich

Aarhus Universitet

D. Nespral

Instituto Astrofisico de Canarias

Universidad de la Laguna

A. Hatzes

Thüringer Landessternwarte Tautenburg

S. Albrecht

Aarhus Universitet

H. Deeg

Instituto Astrofisico de Canarias

Universidad de la Laguna

J. N. Winn

Princeton University

L. Yu

Massachusetts Institute of Technology (MIT)

M. Kuzuhara

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

National Institutes of Natural Sciences

S. Grziwa

Universität zu Köln

A. M. S. Smith

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

E. W. Guenther

Thüringer Landessternwarte Tautenburg

V. Van Eylen

Universiteit Leiden

S. Csizmadia

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Malcolm Fridlund

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

J. Cabrera

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Philipp Eigmüller

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

A. Erikson

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

J. Korth

Universität zu Köln

N. Narita

University of Tokyo

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

National Institutes of Natural Sciences

M. Patzold

Universität zu Köln

H. Rauer

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Technische Universität Berlin

I. Ribas

Universitat Autonoma de Barcelona (UAB)

Astronomical Journal

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

Vol. 153 3

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.3847/1538-3881/aa5cb6

Mer information

Senast uppdaterat

2018-05-29