The eclipsing binary IU Per and its intrinsic oscillations

AbstractThe results of a long-term time-series photometry of the short-period eclipsing binary IU Per are reported. The observation confirms the intrinsic δ Scuti-like pulsation of the star as discovered by previous authors. A photometric solution for the binary system was carried out with the new data. Based on which, the pure oscillation light variations from the mass-accreting primary component were extracted. A Fourier analysis reveals four pulsation modes. Combining with the photometric solution, a preliminary mode identification was given.

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Eclipsing spotted giant star with K2 and historical photometry

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834106 ◽

2018 ◽

Vol 620 ◽

pp. A189 ◽

Cited By ~ 3

Author(s):

K. Oláh ◽

S. Rappaport ◽

T. Borkovits ◽

T. Jacobs ◽

D. Latham ◽

...

Keyword(s):

Binary System ◽

Main Sequence ◽

Rapid Evolution ◽

Magnetic Activity ◽

Primary Component ◽

Physical Parameters ◽

Giant Star ◽

Eclipsing Binary ◽

Giant Stars ◽

Active Stars

Context. Stars can maintain their observable magnetic activity from the pre-main sequence (PMS) to the tip of the red giant branch. However, the number of known active giants is much lower than active stars on the main sequence (MS) since the stars spend only about 10% of their MS lifetime on the giant branch. Due to their rapid evolution it is difficult to estimate the stellar parameters of giant stars. A possibility for obtaining more reliable stellar parameters for an active giant arises when it is a member of an eclipsing binary system. Aims. We have discovered EPIC 211759736, an active spotted giant star in an eclipsing binary system during the Kepler K2 Campaign 5. The eclipsing nature allows us to much better constrain the stellar parameters than in most cases of active giant stars. Methods. We have combined the K2 data with archival HATNet, ASAS, and DASCH photometry, new spectroscopic radial velocity measurements, and a set of follow-up ground-based BVRCIC photometric observations, to find the binary system parameters as well as robust spot models for the giant at two different epochs. Results. We determined the physical parameters of both stellar components and provide a description of the rotational and long-term activity of the primary component. The temperatures and luminosities of both components were examined in the context of the Hertzsprung–Russell diagram. We find that both the primary and the secondary components deviate from the evolutionary tracks corresponding to their masses in the sense that the stars appear in the diagram at lower masses than their true masses. Conclusions. We further evaluate the proposition that traditional methods generally result in higher masses for active giants than what is indicated by stellar evolution tracks in the HR diagram. A possible reason for this discrepancy could be a strong magnetic field, since we see greater differences in more active stars.

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Variability of the Light Curves of the Close Binary GR Tauri

International Astronomical Union Colloquium ◽

10.1017/s0252921100001585 ◽

2002 ◽

Vol 187 ◽

pp. 337-338

Author(s):

A. Yamasaki ◽

M. Takeda ◽

T. Yamauchi ◽

G. Takada ◽

S. Hattori

Keyword(s):

Binary System ◽

The State ◽

Light Curves ◽

Close Binary ◽

Eclipsing Binary ◽

Short Period ◽

Contact Binary

AbstractVariability of the light curves of the short-period eclipsing binary system GR Tau (, almost-contact binary) is studied. It is found that GR Tau experienced both the state which is characterized by asymmetric light curves and the state characterized by symmetrical light curves.

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δ Sct-Type Pulsators in Eclipsing Binary Systems: the Case of RZ Cas

International Astronomical Union Colloquium ◽

10.1017/s0252921100015670 ◽

2002 ◽

Vol 185 ◽

pp. 102-103

Author(s):

E. Rodríguez ◽

V. Costa ◽

M.J. López-González ◽

J.M. García ◽

S.L. Kim ◽

...

Keyword(s):

Binary System ◽

Binary Systems ◽

Hot Spot ◽

Primary Component ◽

Roche Lobe ◽

Light Curves ◽

Eclipsing Binary ◽

Preliminary Results ◽

The Impact

AbstractRZ Cas is an Algol-type eclipsing binary system where the primary component was recently discovered as a δ Set pulsator. A three-continent multisite photometric campaign was carried out during 1999. Preliminary results are reported here indicating a semi-detached system where the secondary fills its Roche lobe. The light curves also suggest a hot spot on the surface of the primary component as a consequence of the impact of the mass stream from the secondary. The pulsational behaviour can be well described with only one frequency.

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The multiple system Sk-67°18 in the LMC

Symposium - International Astronomical Union ◽

10.1017/s0074180900202076 ◽

1995 ◽

Vol 163 ◽

pp. 251-253 ◽

Cited By ~ 1

Author(s):

V. S. Niemela ◽

W. Seggewiss ◽

A. F. J. Moffat

Keyword(s):

Binary System ◽

Radial Velocity ◽

Spectral Type ◽

Orbital Period ◽

Large Magellanic Cloud ◽

Primary Component ◽

Magellanic Cloud ◽

Bright Star ◽

High Mass ◽

Eclipsing Binary

The bright star Sk—67°18 (Brey 5) in the Large Magellanic Cloud (LMC) contains an eclipsing binary system. Our radial velocity study reveals that the orbital period is almost exactly two days. The spectra also show that the star's primary component is not of spectral type WN, but that the star is rather an Of+O type binary where the primary is probably of type O3f*. Furthermore, Sk—67°18 appears to be a high-mass multiple system.

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KIC 10486425: A Kepler eclipsing binary system with a pulsating component

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313014919 ◽

2013 ◽

Vol 9 (S301) ◽

pp. 433-434 ◽

Cited By ~ 2

Author(s):

Filiz Kahraman Aliçavuş ◽

Esin Soydugan

Keyword(s):

Binary System ◽

Fourier Analysis ◽

Light Curve ◽

Frequency Analysis ◽

Dominant Frequency ◽

Eclipsing Binary

AbstractWe present frequency analysis of the Kepler light curve of KIC 10486425, an eclipsing binary system with a pulsating component. The parameters of the binary were obtained by modelling the light curve with the Wilson-Devinney program. The residuals from this modelling were subject to Fourier analysis which allowed us to detect 120 periodic terms characteristic for γ Dor-type pulsations. The dominant frequency of these changes amounts to 1.3189 d−1.

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Short-Period Light Variation of an Eclipsing Binary System: RZ Cassiopeiae

The Astronomical Journal ◽

10.1086/321109 ◽

2001 ◽

Vol 122 (1) ◽

pp. 418-424 ◽

Cited By ~ 29

Author(s):

Osamu Ohshima ◽

Shin-ya Narusawa ◽

Hidehiko Akazawa ◽

Kikuichi Arai ◽

Mitsugu Fujii ◽

...

Keyword(s):

Binary System ◽

Light Variation ◽

Eclipsing Binary ◽

Short Period

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Light and colour curve observations and analysis of the short period eclipsing binary system UV Psc

Astrophysics and Space Science ◽

10.1007/bf00638905 ◽

1979 ◽

Vol 63 (2) ◽

pp. 319-349 ◽

Cited By ~ 17

Author(s):

Aziz R. Sadik

Keyword(s):

Binary System ◽

Eclipsing Binary ◽

Colour Curve ◽

Short Period

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SX Piscium: A near-contact mass-transferring binary with a possible brown dwarf companion

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psz086 ◽

2019 ◽

Vol 71 (5) ◽

Author(s):

Zhi Hua Wang ◽

Li Ying Zhu

Keyword(s):

Binary Star ◽

Mass Transfer Rate ◽

Primary Component ◽

Brown Dwarf ◽

Precision Data ◽

Eclipsing Binary ◽

Short Period ◽

Contact Mass ◽

Photometric Monitoring ◽

Mass Transfers

Abstract SX Psc is a short-period Algol-type eclipsing binary whose photometric analysis has long been ignored. Our photometric monitoring of this target covered from 2001 December to 2018 November. Aside from some curves observed at the primary eclipses, the complete four-color light curves in the BVRcIc band were also obtained. Photometric solutions were determined based on the Wilson–Devinney method. It is found that SX Psc is a semidetached binary where the inner Roche lobe of the secondary component has been filled. The filling factor for the primary is about 85% along with an inclination of ${89{^{\circ}_{.}}8}$, indicating that it is a near-contact total eclipsing binary system. Meanwhile, analysis of the O − C curve revealed that the orbital period is increasing continuously at a rate of dP/dt = 4.64(4) × 10−8 d yr−1. This is due to the mass transfers from the secondary to the primary component, which is in accord with the semidetached configuration of this binary star. With the assumption of conservative evolution, the mass transfer rate is estimated as $1.96\times 10^{-8}\, M_{\odot }$ yr−1. By deducting the long-term increasing trend in the O − C diagram, the high-precision data exhibits a cyclic variation, whereas it might be caused by the Applegate mechanism. Moreover, according to the light travel-time effect, there should be a candidate brown dwarf with a mass of no less than $m\,_3 = 0.067\, M_{\odot }$ orbiting the eclipsing binary. This is perhaps a unique case for an Algol-type binary accompanied by a substellar object.

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