J 2022

Companions to Kepler giant stars: A long-period eccentric sub-stellar companion to KIC 3526061 and a stellar companion to HD 187878

KARJALAINEN, Marie; Raine KARJALAINEN; Artie P HATZES; Holger LEHMANN; Pierre KERVELLA et. al.

Základní údaje

Originální název

Companions to Kepler giant stars: A long-period eccentric sub-stellar companion to KIC 3526061 and a stellar companion to HD 187878

Autoři

KARJALAINEN, Marie (garant); Raine KARJALAINEN; Artie P HATZES; Holger LEHMANN; Pierre KERVELLA; Saskia HEKKER; Van Winckel HANS; Jakub UBERLAUER; Michaela VÍTKOVÁ ORCID (203 Česká republika, domácí); Marek SKARKA (203 Česká republika, domácí); Petr KABATH; Saskia PRINS; Andrew TKACHENKO; William D COCHRAN a Alain JORISSEN

Vydání

Astronomy and Astrophysics, EDP Sciences, 2022, 0004-6361

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Francie

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 6.500

Kód RIV

RIV/00216224:14310/22:00128603

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000898961600011

EID Scopus

2-s2.0-85145254278

Klíčová slova anglicky

methods: observational; techniques: radial velocities; techniques: spectroscopic; stars: individual: KIC 3526061; stars: individual: HD 187878; brown dwarfs

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 3. 4. 2023 12:11, Mgr. Marie Novosadová Šípková, DiS.

Anotace

V originále

Context. Our knowledge of populations and the occurrence of planets orbiting evolved intermediate-mass stars is still incomplete. In 2010 we started a planet search programme among 95 giant stars observed by the Kepler mission to increase the sample of giant stars with planets and with reliable estimates of stellar masses and radii. Aims. We present the two systems from our planet search programme whose companions we were able to characterise: KIC 3526061 and HD 187878. Methods. We used precise stellar radial velocity measurements taken with four different echelle spectrographs to derive an orbital solution. We used Gaia astrometric measurements to obtain the inclination of the HD 187878 system and Kepler photometric observations to estimate the stellar mass and radius. Results. We report the discovery of a sub-stellar companion and a stellar companion around two intermediate-mass red giant branch stars. KIC 3526061 b is most likely a brown dwarf with a minimum mass of 18.15 +/- 0.44 M-Jupiter in a long-period eccentric orbit, with orbital period 3552(-135)(+158) d and orbital eccentricity e = 0.85 +/- 0.01. It is the most evolved system found having a sub-stellar companion with such a high eccentricity and wide separation. HD 187878 B has a minimum mass of 78.4 +/- 2.0 M-Jupiter. Combining the spectroscopic orbital parameters with the astrometric proper motion anomaly, we derived an orbital inclination i = 9.8(-0.6)(+0.4) deg, which corresponds to the companion's mass in the stellar regime of 0.51(-0.02)(+0.04) M-circle dot. Conclusions. A sub-stellar companion of KIC 3526061 extends the sample of known red giant branch stars with sub-stellar companions on very eccentric wide orbits, and might provide a probe of the dynamical evolution of such systems over time.