Search Publications
Relations between global seismic parameters and activity cycles of the Sun
Chang, Heon-Young; Kim, Ki-Beom
It is suggested that the dependency of the global asteroseismic parameters on stellar properties such as magnetic activity is carefully calibrated with a homogenous data sample in stellar parameters in the sense that the empirical scaling relations of the global asteroseismic parameters are used in estimating fundamental stellar properties. As an …
Orbital period changes in IO Cep, IM Cep and TX Ari: Path to masses of distant components
Bakış, V.; Eker, Z.; Bakış, H. +7 more
Three Algol-type binary systems (IO Cep, IM Cep and TX Ari) showing cyclic orbital period changes are studied. The combination of time of minimum data from the ground-based observations together with high precision photometric data from the TESS satellite enabled us to estimate the basic light curve elements of binary systems and mass functions fo…
An astrometric and photometric study of the young open cluster NGC 2168 and its possible member [NBN2015]77
Hendy, Y. H. M.; Shokry, A.; Saad, S. M. +2 more
We present an astrometric and photometric study of the young open star cluster NGC 2168 and its proposed member [NBN2015]77. NGC 2168 was investigated by combining data from both the Gaia-ESO DR2 and the 2MASS databases. The photometric analysis and light curve modeling of the W UMa star [NBN2015] 77 in V and R bands was performed using the Wilson…
First photometric investigation of two short-period eclipsing binaries ASAS J105115-6032.1 and GDS J1056047-604149
Sarotsakulchai, Thawicharat; Soonthornthum, Boonrucksar; Liu, Nian-Ping +1 more
ASAS J105115-6032.1 (hereafter ASAS J1051) and GDS J1056047-604149 (hereafter GDS J1056) are two short-period contact binaries close to each other in the Antarctica sky area. By analyzing the light curves from AST3-1, the first photometric solutions are presented using the Wilson-Devinney (W-D) method. It is detected that both systems are W-type c…
A photometric study of V608 Cam: apparent period changes as a result of surface activity
Wolf, M.; Walter, F.; Šebek, F.
The VRI light curves were measured for the low-mass eclipsing binary V608 Cam as a part of our long-term observational project for studying of eclipsing binaries with a short orbital period. The TESS light curve solution in PHOEBE results to the detached configuration, where the temperature of the primary component was fixed to T1 = 530…
A possible large-scale alignment of galaxy spin directions - Analysis of 10 datasets from SDSS, Pan-STARRS, and HST
Shamir, Lior
Multiple observations made by several different telescopes have shown asymmetry between the number of spiral galaxies rotating in opposite directions in different parts of the sky. One of the immediate questions regarding the possible asymmetry of the spin directions is whether the distribution forms a cosmological-scale axis. This paper analyzes …
Detailed analysis of an eccentric TESS binary star with solar-type components: TIC 284613090
Aliçavuş, Fahri
Eclipsing binary stars are significant objects for understanding stellar evolution, stellar population synthesis, and galaxy dynamics. Thanks to the increasing number of high-quality photometric data of space observations, the sensitivity of the fundamental astrophysical parameters (mass M, radius R) has risen and this situation has highlighted th…
Interstellar polarization and extinction toward the Recurrent Nova T CrB
Nikolov, Yanko
Spectropolarimetry is a powerful tool for diagnostic of interstellar matter and gives information about the geometry of the ejected material after the novae outbursts. In this paper are presented spectropolarimetric observations of the recurrent nova T CrB at quiescence obtained with FoReRo2 attached to the Cassegrain focus of the 2.0 m RCC telesc…
The overcontact binary SS arietis
Nelson, Robert H.
New radial velocity and photometric data for SS Ari have been obtained and analysed using the 2003 versions of the Wilson-Devinney code. Values for fundamental quantities have been obtained: M1 = 0.510 (15) M⊙, M2 = 1.521 (26) M⊙, R1 = 0.87 (2) R⊙, R2 = 1.42 (2) R⊙
The two eccentric eclipsing binaries in multiple systems: V539 Arae and V335 Serpentis
Wolf, M.; Zejda, M.; Mašek, M. +4 more
We present new results of our long-term observational project to analyze the variations of the orbital period for early-type eccentric eclipsing binaries. Altogether 77 new mid-eclipse times were measured or derived for two eclipsing binaries, namely V539 Ara and V335 Ser. Based on current O - C diagrams, we found in both systems that times of min…