nu Gem: A Hierarchical Triple System with an Outer Be Star

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F21%3A00548140" target="_blank" >RIV/67985815:_____/21:00548140 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.3847/1538-4357/ac062c" target="_blank" >https://doi.org/10.3847/1538-4357/ac062c</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/ac062c" target="_blank" >10.3847/1538-4357/ac062c</a>

Jazyk výsledku

angličtina

Název v původním jazyce

nu Gem: A Hierarchical Triple System with an Outer Be Star

Popis výsledku v původním jazyce

Time series of spectroscopic, speckle-interferometric, and optical long-baseline-interferometric observations confirm that nu Gem is a hierarchical triple system. It consists of an inner binary composed of two B-type stars and an outer classical Be star. Several photospheric spectral lines of the inner components were disentangled, revealing two stars with very different rotational broadening (similar to 260 and similar to 140 km s(-1), respectively), while the photospheric lines of the Be star remain undetected. From the combined spectroscopic and astrometric orbital solution it is not possible to unambiguously cross identify the inner astrometric components with the spectroscopic components. In the preferred solution based on modeling of the disentangled line profiles, the inner binary is composed of two stars with nearly identical masses of 3.3 M (circle dot) and the more rapidly rotating star is the fainter one. These two stars are in a marginally elliptical orbit (e = 0.06) about each other with a period of 53.8 days. The third star also has a mass of 3.3 M (circle dot) and follows a more eccentric (e = 0.24) orbit with a period of 19.1 yr. The two orbits are codirectional, and at inclinations of 79 degrees and 76 degrees of the inner and the outer orbit, respectively, about coplanar. No astrometric or spectroscopic evidence could be found that the Be star itself is double. The system appears dynamically stable and not subject to eccentric Lidov-Kozai oscillations. After disentangling, the spectra of the components of the inner binary do not exhibit peculiarities that would be indicative of past interactions. Motivations for a wide range of follow-up studies are suggested.

Název v anglickém jazyce

nu Gem: A Hierarchical Triple System with an Outer Be Star

Popis výsledku anglicky

Time series of spectroscopic, speckle-interferometric, and optical long-baseline-interferometric observations confirm that nu Gem is a hierarchical triple system. It consists of an inner binary composed of two B-type stars and an outer classical Be star. Several photospheric spectral lines of the inner components were disentangled, revealing two stars with very different rotational broadening (similar to 260 and similar to 140 km s(-1), respectively), while the photospheric lines of the Be star remain undetected. From the combined spectroscopic and astrometric orbital solution it is not possible to unambiguously cross identify the inner astrometric components with the spectroscopic components. In the preferred solution based on modeling of the disentangled line profiles, the inner binary is composed of two stars with nearly identical masses of 3.3 M (circle dot) and the more rapidly rotating star is the fainter one. These two stars are in a marginally elliptical orbit (e = 0.06) about each other with a period of 53.8 days. The third star also has a mass of 3.3 M (circle dot) and follows a more eccentric (e = 0.24) orbit with a period of 19.1 yr. The two orbits are codirectional, and at inclinations of 79 degrees and 76 degrees of the inner and the outer orbit, respectively, about coplanar. No astrometric or spectroscopic evidence could be found that the Be star itself is double. The system appears dynamically stable and not subject to eccentric Lidov-Kozai oscillations. After disentangling, the spectra of the components of the inner binary do not exhibit peculiarities that would be indicative of past interactions. Motivations for a wide range of follow-up studies are suggested.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Astrophysical Journal

ISSN

0004-637X

e-ISSN

1538-4357

Svazek periodika

916

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

18

Strana od-do

24

Kód UT WoS článku

000675616300001

EID výsledku v databázi Scopus

2-s2.0-85112593362