J 2016

New analysis of the light time effect in TU Ursae Majoris

LIŠKA, Jiří, Marek SKARKA, Zdeněk MIKULÁŠEK, Miloslav ZEJDA, Marek CHRASTINA et. al.

Základní údaje

Originální název

New analysis of the light time effect in TU Ursae Majoris

Autoři

LIŠKA, Jiří (203 Česká republika, garant, domácí), Marek SKARKA (203 Česká republika, domácí), Zdeněk MIKULÁŠEK (203 Česká republika, domácí), Miloslav ZEJDA (203 Česká republika, domácí) a Marek CHRASTINA (703 Slovensko)

Vydání

Astronomy and Astrophysics, EDP Sciences, 2016, 1432-0746

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: 5.014

Kód RIV

RIV/00216224:14310/16:00090005

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000375318300106

Klíčová slova anglicky

binaries: general; techniques: photometric; techniques: radial velocities; stars: variables: RR Lyrae; methods: data analysis

Štítky

Změněno: 7. 4. 2017 13:45, Ing. Andrea Mikešková

Anotace

V originále

We investigate in detail the LiTE of the most probable binary candidate TU UMa. We used a new code applied on previously available and newly determined maxima timings to confirm binarity and refine parameters of the orbit of the RRab component in the binary system. The binary hypothesis is also tested using RV measurements. We used new approach to determine brightness maxima timings based on template fitting. This can also be used on sparse or scattered data. This approach was successfully applied on measurements from different sources. To determine the orbital parameters of the double star TU UMa, we developed a new code to analyse LiTE that also includes secular variation in the pulsation period. Its usability was successfully tested on CL Aur, an eclipsing binary with mass-transfer in a triple system that shows similar changes in the O-C diagram. Since orbital motion would cause systematic shifts in mean RVs (dominated by pulsations), we computed and compared our model with centre-of-mass velocities. They were determined using high-quality templates of RV curves of RRab stars. Maxima timings adopted from the GEOS database (168) together with those newly determined from sky surveys and new measurements (85) were used to construct an O-C diagram spanning almost five proposed orbital cycles. This data set is three times larger than data sets used by previous authors. Modelling of the O-C dependence resulted in 23.3-year orbital period, which translates into a minimum mass of the second component of about 0.33 M_s. Secular changes in the pulsation period of TU UMa over the whole O-C diagram were satisfactorily approximated by a parabolic trend with a rate of -2.2 ms/yr. To confirm binarity, we used RV measurements from nine independent sources. Although our results are convincing, additional long-term monitoring is necessary to unambiguously confirm the binarity of TU UMa.

Návaznosti

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