J 2016

Cyclic variations in O-C diagrams of field RR Lyrae stars as a result of LiTE

LIŠKA, Jiří, Marek SKARKA, Miloslav ZEJDA, Zdeněk MIKULÁŠEK, S. N. DE VILLIERS et. al.

Základní údaje

Originální název

Cyclic variations in O-C diagrams of field RR Lyrae stars as a result of LiTE

Autoři

LIŠKA, Jiří (203 Česká republika, garant, domácí), Marek SKARKA (203 Česká republika, domácí), Miloslav ZEJDA (203 Česká republika, domácí), Zdeněk MIKULÁŠEK (203 Česká republika, domácí) a S. N. DE VILLIERS (710 Jižní Afrika)

Vydání

Monthly Notices of the Royal Astronomical Society, Priestley and Weale, 2016, 0035-8711

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 4.961

Kód RIV

RIV/00216224:14310/16:00090007

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000379830700072

Klíčová slova anglicky

methods: data analysis; techniques: photometric; binaries: general; stars: horizontal branch; stars: variables: RR Lyrae

Štítky

Změněno: 31. 3. 2017 10:50, Ing. Andrea Mikešková

Anotace

V originále

This paper presents an extensive overview of known and proposed RR Lyrae stars in binaries. The aim is to revise and extend the list with new Galactic field systems. We utilized maxima timings for 11 RRab type stars with suspicious behaviour from the GEOS data base, and determined maxima timings from data of sky surveys and our own observations. This significantly extended the number of suitable maxima timings. We modelled the proposed Light Time Effect (LiTE) in O-C diagrams to determine orbital parameters for these systems. In contrast to recent studies, our analysis focused on decades-long periods instead of periods in the order of years. Secondary components were found to be predominantly low-mass objects. However, for RZ Cet and AT Ser the mass of the suspected companion of more than one solar mass suggests that it is a massive white dwarf, a neutron star or even a black hole. We found that the semimajor axes of the proposed orbits are between 1 and 20 au. Because the studied stars belong to the closest RR Lyraes, maximal angular distances between components during orbit should at least be between 1 and 13 mas and this improves the chance to detect both stars using current telescopes. However, our interpretation of the O-C diagrams as a consequence of the LiTE should be considered as preliminary without reliable spectroscopic measurements. On the other hand, our models give a prediction of the period and radial velocity evolution which should be sufficient for plausible proof of binarity.

Návaznosti

LH14300, projekt VaV
Název: Výzkum zvláštních proměnných hvězd
Investor: Ministerstvo školství, mládeže a tělovýchovy ČR, Výzkum zvláštních proměnných hvězd