Greening of the brown-dwarf desert. EPIC 212036875b: a 51 M-J object in a 5-day orbit around an F7V star

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F19%3A00511639" target="_blank" >RIV/67985815:_____/19:00511639 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216224:14310/19:00111909 RIV/00216208:11320/19:10415022

Výsledek na webu

<a href="https://doi.org/10.1051/0004-6361/201935505" target="_blank" >https://doi.org/10.1051/0004-6361/201935505</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201935505" target="_blank" >10.1051/0004-6361/201935505</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Greening of the brown-dwarf desert. EPIC 212036875b: a 51 M-J object in a 5-day orbit around an F7V star

Popis výsledku v původním jazyce

Our aim is to investigate the nature and formation of brown dwarfs by adding a new well-characterised object, in terms of its mass, radius and bulk density, to the currently small sample of less than 20 transiting brown dwarfs. EPIC 212036875 b is a rare object that resides in the brown-dwarf desert. In the mass-density diagram for planets, brown dwarfs, and stars, we find that all giant planets and brown dwarfs follow the same trend from similar to 0.3 M-J to the turn-over to hydrogen burning stars at similar to 73 M-J. EPIC 212036875 b falls close to the theoretical model for mature H/He dominated objects in this diagram as determined by interior structure models. We argue that EPIC 212036875 b formed via gravitational disc instabilities in the outer part of the disc, followed by a quick migration. Orbital tidal circularisation may have started early in its history for a brief period when the brown dwarf's radius was larger. The lack of spin-orbit synchronisation points to a weak stellar dissipation parameter (Q(star)' greater than or similar to 10(8)), which implies a circularisation timescale of greater than or similar to 23 Gyr, or suggests an interaction between the magnetic and tidal forces of the star and the brown dwarf.

Název v anglickém jazyce

Greening of the brown-dwarf desert. EPIC 212036875b: a 51 M-J object in a 5-day orbit around an F7V star

Popis výsledku anglicky

Our aim is to investigate the nature and formation of brown dwarfs by adding a new well-characterised object, in terms of its mass, radius and bulk density, to the currently small sample of less than 20 transiting brown dwarfs. EPIC 212036875 b is a rare object that resides in the brown-dwarf desert. In the mass-density diagram for planets, brown dwarfs, and stars, we find that all giant planets and brown dwarfs follow the same trend from similar to 0.3 M-J to the turn-over to hydrogen burning stars at similar to 73 M-J. EPIC 212036875 b falls close to the theoretical model for mature H/He dominated objects in this diagram as determined by interior structure models. We argue that EPIC 212036875 b formed via gravitational disc instabilities in the outer part of the disc, followed by a quick migration. Orbital tidal circularisation may have started early in its history for a brief period when the brown dwarf's radius was larger. The lack of spin-orbit synchronisation points to a weak stellar dissipation parameter (Q(star)' greater than or similar to 10(8)), which implies a circularisation timescale of greater than or similar to 23 Gyr, or suggests an interaction between the magnetic and tidal forces of the star and the brown dwarf.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astronomy & Astrophysics

ISSN

1432-0746

e-ISSN

—

Svazek periodika

628

Číslo periodika v rámci svazku

August

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

14

Strana od-do

A64

Kód UT WoS článku

000480314000002

EID výsledku v databázi Scopus

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