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TIC 452991707 and TIC 452991693 as a Candidate Sextuple System with Three Eclipsing Binaries

Zasche P., Henzl Z.

Acta Astronomica

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2022

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Vol. 72, No. 2

103--111

EN

We present the discovery of a rare system detected in the TESS data showing three different eclipsing-like signals. TIC 452991707 and TIC 452991693 seem to be the second such system on the sky, whose two components separated about 16" are gravitationally bounded, or comprise a co-moving pair. The three periods detected from the TESS data are: PA=1.46155 d, PB= 1.77418 d, and PC=1.03989 d, respectively. The A and B periods belong to TIC 452991707, while the C comes from the component TIC 452991693. The pair A shows the deepest eclipses, and its orbit is very slightly eccentric. The third period C has lowest amplitude (eclipsing or ellipsoidal nature), but originates from TIC 452991693, which is connected to A+B because both visual components share similar proper motion and distance. Long-term collection of data from older photometry from various surveys also shows that the two inner pairs A and B orbit around their barycenter. Its period is probably of a few years, but for a final derivation of its orbital parameters one needs more up-to-date data. Hence, we call for new observations of this amazing system.

2

Speckle Observations with PISCO in Calern (France): Orbit and Mass Determinations for 22 Visual Binaries

Ling J. F., Scardia M., Prieur J.-L., Argyle R. W., Aristidi E., Zanutta A., Abe L., Bendjoya P., Rivet J.-P., Vernet D.

Acta Astronomica

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2022

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Vol. 72, No. 2

113--140

EN

This paper presents orbits and masses for 22 visual double stars, partly derived using their last observations made with the speckle camera PISCO. For 13 of them we have determined their first-time orbits. Masses were calculated from Hipparcos and Gaia parallaxes when available, and from dynamical parallaxes otherwise. They are compared with masses deduced from spectral types. Other physical and orbital properties are also considered.

3

Light Curve Modeling of Four Short-Period W UMa Binaries

Čeki A., Latković O.

Acta Astronomica

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2022

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Vol. 72, No. 3

183--194

EN

We use extensive model grids to estimate the global parameters of four partially-eclipsing W UMa contact binaries near the period cutoff. All four systems consist of K-type main sequence primaries and M-type secondaries that appear undersized and underluminous for their masses because of the energy transfer through the common envelope. Three of the four stars exhibit light curve asymmetry that is explained in terms of magnetic activity and modeled with dark spots. We discuss the reliability of the photometric mass ratios and derived absolute parameters in context of total or partial eclipses and compare them with a sample of totally-eclipsing short-period W UMa systems from the literature.

4

A Method of Improving Standard Stellar Luminosities with Multiband Standard Bolometric Corrections

Bakış V., Eker Z.

Acta Astronomica

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2022

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Vol. 72, No. 3

195--232

EN

Standard luminosity (L) of 406 main-sequence stars with the most accurate astrophysical parameters are calculated from their absolute magnitudes and bolometric corrections at Johnson BV, and Gaia EDR3 G, GBP, GRP filters. Required multiband BC and BC-Teff relations are obtained first from the parameters of 209 Double-lined Detached Eclipsing Binaries with main-sequence components and Gaia EDR3 parallaxes. A simplified SED is formulated to give filter dependent component light contributions and interstellar dimming, which are essential in computing BC of a component, virtually at any filter. The mean standard L of a star is calculated from the mean Mbolwhich is a mathematical average of independent Mboll values predicted at different filters, while the uncertainty of L is the uncertainty propagated from the uncertainty of the mean Mbol. The mean standard L of the sample stars are compared to the corresponding L values according to the Stefan-Boltzmann law. A very high correlation (R2>0.999) is found. Comparing histogram distributions of errors shows that uncertainties associated with the mean standard L (peak at ≈2.5 per cent) are much smaller than the uncertainties of L (peak at ≈8 per cent) by the Stefan-Boltzmann law. Increasing the number of filters used in predicting the mean Mbol increases the accuracy of the standard stellar luminosity. Extinction law, color-color relations and color excess vs. color excess relations for Gaia passbands are presented for the first time for main-sequence stars.

5

Over a Century of δ Ceti Variability Investigation

Śreniawska E., Kamiński K., Kamińska M. K., Tokarek J., Zgórz M.

Acta Astronomica

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2021

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Vol. 71, No. 4

297--310

EN

We present results of a 2014-2018 campaign of radial velocity measurements of δ Ceti. Combining our determination of pulsation period with historical data we conclude that the most likely explanation of observed changes is the presence of a secondary component with a minimum mass of 1.10±0.05 Mo on an orbit with a period of 169±6 yr. Consequently, we revised the intrinsic, evolutionary period change rate to be not larger than 0.018±0.004 s/century, which is significantly lower than previous estimations and is consistent with evolutionary models. We did not find any significant multiperiodic frequencies in radial velocity periodograms such as those reported in the photometric data from the MOST satellite. Using interferometric angular size of δ Ceti from JMMC Stellar Diameters Catalogue we determined several physical parameters of the star with bolometric flux method. They turned out to be consistent with most previous determinations, confirming lower mass and slower evolution of δ Ceti than obtained using different methods.

6

On the Pulsations of the δ Scuti Star of the Binary System KIC 6629588

Liakos A.

Acta Astronomica

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2020

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Vol. 70, No. 4

265--289

EN

his work includes a comprehensive analysis of the Kepler detached eclipsing binary system KIC 6629588 that aims at the detailed study of the oscillation properties of its pulsating component. Ground-based spectroscopic observations were obtained and used to classify the components of the system. The spectroscopic results were used as constraints for the modeling of the short-cadence Kepler light curves and for the estimation of the absolute parameters of the components. Furthermore, the light curve residuals are analyzed using Fourier transformation techniques in order to search for pulsation frequencies. The primary component of the system is identified as a δ Sct star that pulsates in seven eigenfrequencies in the range of 13-22 d-1, while more than 270 combination frequencies were also detected. The absolute and the oscillation parameters of this pulsating star are compared with those of other δ Sct stars members of detached binary systems using evolutionary and correlation diagrams. Finally, the distance to the system is also estimated.

7

A Comprehensive Study of the Eclipsing Binaries V1241 Tau and GQ Dra

Ulaş B., Gazeas K., Liakos A., Ulusoy C., Stateva I., Erkan N., Napetova M., Iliev I. K.

Acta Astronomica

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2020

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Vol. 70, No. 3

219--240

EN

We present new photometric and spectroscopic observations and analyses for the eclipsing binary systems V1241 Tau and GQ Dra. Our photometric light and radial velocity curve analyses combined with the TESS light curves show that both are conventional semi-detached binary systems. Their absolute parameters are also derived. We present the O-C analyses of the systems and we propose the most likely orbital period modulating mechanisms. Furthermore, Fourier analyses are applied to the photometric residual data of the systems to check for the pulsational behavior of the components. We conclude that the primary component of the system GQ Dra is a δ Sct type pulsator with a dominant pulsation frequency of 18.58 d-1 based on our B filter residual light curve although it can not be verified by 30-minute cadence TESS data. No satisfactory evidence of pulsational behavior for V1241 Tau was verified. Finally, the evolutionary tracks of the components of both systems are calculated. Their locations within evolutionary diagrams are compared with other Algol-type systems.

8

Triple Eccentric Systems V0345 Lac, YY Sgr, and DR Vul

Wolf M., Zasche P., Kučáková H., Mašek M., Hoňková K., Juryšek J., Paschke A., Šmelcer L., Zejda M.

Acta Astronomica

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2019

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Vol. 69, No. 1

63--78

EN

We present more results of our long-term observational project to analyze the variations of the orbital period for early-type eccentric eclipsing binaries. About sixty new precise mid-eclipse times were measured or derived for three eclipsing binaries, namely V0345 Lac, YY Sgr, and DR Vul. Based on current O-C diagrams, we found in all cases that beside the typical apsidal motion the times of minima show additional cyclical changes likely caused by a third body orbiting the eclipsing pair. The new light curve solution of V0345 Lac results in a moderate orbital eccentricity (e=0.26) of this binary. The periods of apsidal motion are 1580 yr, 295 yr, and 36 yr, respectively. The relativistic contributions to the total apsidal-motion rate are small for all three eccentric binaries - about 5-14%. The third-body orbital periods are relatively short: 24 yr, 19 yr and 66 yr, and the minimal masses of third bodies are: 2.0 M☉, 0.8 M☉, and 7.2 M☉, respectively.

9

Roche Modeling and Evolutionary History of Multiple Low Mass Contact Binary Systems

Alton K. B., Stępień K.

Acta Astronomica

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2018

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Vol. 68, No. 4

449--482

EN

The Northern Sky Variable Survey (NSVS) has been a rich source of variable stars many of which have only been studied to a limited extent. Herein we describe five eclipsing binary systems that were first detected by the ROTSE-I telescope and ultimately shown to be low mass contact binaries. Photometric data (B, V and Ic) acquired from MU Cnc (NSVS 10133793, TYC 1397-1030-1), V596 Peg (NSVS 6225359, GSC 2765-0348), TYC 1597-2327-1 (NSVS 11082150), GSC 2723-2376 (NSVS 8849526) and GSC 4946-0765 (NSVS 13176410) were used to calculate an orbital period for each system along with new linear ephemerides. Except for MU Cnc, the limited number of time-of-minimum values precluded the characterization of any long-term period change. Since a total eclipse is observed with all five systems, Roche modeling based on the Wilson-Devinney W-D code yielded in each instance a well-constrained photometric value for the mass ratio. Using the evolutionary model of cool close binaries we searched for possible progenitors of the investigated binaries. The best fit is obtained if the initial binaries have orbital periods from the interval between 2.4–3.4 d, total masses between 6% and 9% higher than presently observed and mass ratios between 2.2 and 3.3. The model progenitors need between 7.5–10 Gyr to attain the presently observed parameters of the variables. The present periods of three models slowly increase with simultaneous mass ratio decrease, which suggests the formation of the common envelope in the future. However, in four other models the period decreases and the model computations predict the ultimate overflow of the outer Roche lobe.

10

Predicted Microlensing Events by Nearby Very-Low-Mass Objects: Pan-STARRS DR1 vs. Gaia DR2

Nielsen M. B., Bramich D. M.

Acta Astronomica

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2018

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Vol. 68, No. 4

351--370

EN

Microlensing events can be used to directly measure the masses of single field stars to a precision of ≈1–10%. The majority of direct mass measurements for stellar and sub-stellar objects typically only come from observations of binary systems. Hence microlensing provides an important channel for direct mass measurements of single stars. The Gaia satellite has observed ≈1.7 billion objects, and analysis of the second data release has recently yielded numerous event predictions for the next few decades. However, the Gaia catalog is incomplete for nearby very-low-mass objects such as brown dwarfs for which mass measurements are most crucial. We employ a catalog of very-low-mass objects from Pan-STARRS data release 1 (PDR1) as potential lens stars, and we use the objects from Gaia data release 2 (GDR2) as potential source stars. We then search for future microlensing events up to the year 2070. The Pan-STARRS1 objects are first cross-matched with GDR2 to remove any that are present in both catalogs. This leaves a sample of 1718 possible lenses. We fit MIST isochrones to the Pan-STARRS1, AllWISE and 2MASS photometry to estimate their masses. We then compute their paths on the sky, along with the paths of the GDR2 source objects, until the year 2070, and search for potential microlensing events. Source-lens pairs that will produce a microlensing signal with an astrometric amplitude of greater than 0.131 mas, or a photometric amplitude of greater than 0.4 mmag, are retained.

11

Hybrid Pulsations and Tidal Splitting detected in the Kepler Eclipsing and Spotted Binary System KIC 6048106

Samadi Ghadim A., Lampens P., Jassur D. M.

Acta Astronomica

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2018

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Vol. 68, No. 4

425--447

EN

We present a new asteroseismic analysis of KIC 6048106, a Kepler Algol-type eclipsing binary star in a circularized orbit with Porb=1.559361±0.000036 d. Based on a physical model for the binary and its corresponding set of fundamental parameters (Teff=7033±187 K, M1=1.55±0.11 M☉, R1=1.58±0.12 R☉ and Teff=4522±103 K, M2=0.33±0.07 M☉, R2=1.78±0.16 R☉, respectively for the primary and the secondary component), we obtained the residual light curve after removal of the full binary model, including a 290-d activity cycle for the secondary component. In this work, we used the method of Fourier analysis of the residual light curve in combination with least squares optimization for the frequency analysis. We detected seven dominant, independent gravity (g) modes as well as 34 low-amplitude acoustic (p) modes. The g modes in the range of 1.96–2.85 d-1 have a mean spacing of ΔΠmean=1517.92±131.54 s. Though of much lower amplitude, additional significant frequencies were detected in the intervals 7.49–15.2 d-1 and 19–22.5 d-1 (i.e., in the p mode region), with corresponding dominant modes νmax1=11.745±0.001 d-1 and νmax2=20.960±0.002 d-1 From its position in the HR diagram, we conclude that the primary component is the source of the detected hybrid pulsations. Consequently, the pulsation constants, Q, of the high frequencies cover the range of 0.028–0.064 d. Furthermore, ν43 (19.037±0.002 d-1) might correspond to the fundamental radial mode (Q=0.033±0.007 d). The other frequencies in the range of 19–22.5 d-1 could be radial or non-radial overtone modes. Moreover, the low-amplitude p modes show an equidistant splitting by forb, which we interpret as tidal splitting following theoretical predictions.

12

An Almanac of Predicted Microlensing Events for the 21st Century

Bramich D. M., Nielsen M. B.

Acta Astronomica

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2018

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Vol. 68, No. 3

183--203

EN

Using Gaia data release 2 (GDR2), we present an almanac of 2509 predicted microlensing events, caused by 2130 unique lens stars, that will peak between July 25, 2026 and the end of the century. This work extends and completes a thorough search for future microlensing events initiated by Bramich and Nielsen using GDR2. The almanac includes 161 lenses that will cause at least two microlensing events each. A few highlights are presented and discussed, including: (i) an astrometric microlensing event with a peak amplitude of ≈9.7 mas, (ii) an event that will probe the planetary system of a lens with three known planets, and (iii) an event (resolvable from space) where the blend of the lens and the minor source image will brighten by a detectable amount (≈2 mmag) due to the appearance of the minor source image. All of the predicted microlensing events in the almanac will exhibit astrometric signals that are detectable by observing facilities with an angular resolution and astrometric precision similar to, or better than, that of the Hubble Space Telescope (e.g., NIRCam on the James Webb Space Telescope), although the events with the most extreme source-to-lens contrast ratios may be challenging. Ground-based telescopes of at least 1 m in diameter can be used to observe many of the events that are also expected to exhibit a photometric signal.

13

The Triple Eccentric Systems V974 Cyg, RU Mon, and V456 Oph

Wolf M., Zasche P., Kučáková H., Hoňková K., Juryšek J., Mašek M., Uhlař R., Urbaník M.

Acta Astronomica

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2017

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Vol. 67, No. 3

257--271

EN

We present results of a long-term program for timing the eclipses of eccentric eclipsing binaries. About 40 new precise mid-eclipse times were measured for the eclipsing binary V974 Cyg, RU Mon and V456 Oph. Based on current O-C diagrams, we found in all cases that times of minima besides the typical apsidal motion show additional cyclical changes caused very probably by the third bodies orbiting the eclipsing pair. The periods of apsidal motion are 1470 yr, 361 yr and 22.6 yr, respectively. The period of V456 Oph this is one of the shortest known apsidal-motion periods. The relativistic contributions to the total apsidal-motion rate are significant for V974 Cyg (about 30%) and negligible for RU Mon and V456 Oph (1-2.5%). The third-body orbital periods are relatively short: 30.6 yr, 59.8 yr and 7.4 yr, and their minimal masses are 0.40 M☉, 1.6 M☉, and 0.27 M☉, respectively.

14

The Strange Case of OGLE-SMC-ECL-0277

Zasche P., Wolf M., Vraštil J., Fatka P., Galád A., Hornoch K., Janák Z., Janík J., Kortusová E., Kurfürst P., Kušnirák P., Paunzen E., Řezba L., Votruba V., Zejda M., Zieliński P.

Acta Astronomica

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2017

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Vol. 67, No. 3

243--255

EN

The eclipsing system OGLE-SMC-ECL-0277 was found to exhibit unusual photometric variability. Beside its eclipsing nature additional variations with the periodicity of about 1500~d are also seen. Variations of the eclipse depth during the time span of the observational data (mainly taken from the OGLE survey, partly our new ones) are the most pronounced. The complex behavior of all these changes makes this system absolutely unique, no such variability was ever detected and studied in other systems before. Hence, are there some new phenomena, new physics or an unknown effects playing a role? We tried to understand these variations using four different hypotheses (\ie inclination change, spot evolution, and/or pulsation of one or both components) and comparing their results we discussed which of them is the most likely. Neither of the presented hypotheses is able to describe in detail the behavior of OGLE-SMC-ECL-0277. We also discuss a possibility that the variable can be a member of the so-called double periodic variables group.

15

OGLE-LMC-ECL-09937: The Most Massive Algol-Type Binary System with a Mass Measurement Accurate to 2%

Skowron D. M., Kourniotis M., Prieto J. L., Castro N., Bonanos A. Z., Pieńkowski D.

Acta Astronomica

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2017

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Vol. 67, No. 4

329--344

EN

This paper presents a detailed analysis of the light and radial velocity curves of the semi-detached eclipsing binary system OGLE-LMC-ECL-09937. The system is composed of a hot, massive and luminous primary star of a late-O spectral type, and a more evolved, but less massive and luminous secondary, implying an Algol-type system that underwent a mass transfer episode. We derive masses of 21.04±0.34 M☉ and 7.61±0.09 M☉ and radii of 9.93±0.06 R☉ and 9.18±0.04 R☉, for the primary and the secondary component, respectively, which make it the most massive known Algol-type system with masses and radii of the components measured with <2% accuracy. Consequently, the parameters of OGLE-LMC-ECL-09937 provide an important contribution to the sparsely populated high-mass end of the stellar mass distribution, and an interesting object for stellar evolution studies, being a possible progenitor of a binary system composed of two neutron stars.

16

OGLE-ing the Magellanic System: Three-Dimensional Structure of the Clouds and the Bridge using RR Lyrae Stars

Jacyszyn-Dobrzeniecka A. M., Skowron D. M., Mróz P., Soszyński I., Udalski A., Pietrukowicz P., Skowron J., Poleski R., Kozłowski S., Wyrzykowski Ł., Pawlak M., Szymański M. K., Ulaczyk K.

Acta Astronomica

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2017

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Vol. 67, No. 1

1--35

EN

We present a three-dimensional analysis of a sample of 22 859 type ab RR Lyr stars in the Magellanic System from the OGLE-IV Collection of RR Lyr stars. The distance to each object was calculated based on its photometric metallicity and a theoretical relation between color, absolute magnitude and metallicity. The LMC RR Lyr distribution is very regular and does not show any substructures. We demonstrate that the bar found in previous studies may be an overdensity caused by blending and crowding effects. The halo is asymmetrical with a higher stellar density in its north-eastern area, which is also located closer to us. Triaxial ellipsoids were fitted to surfaces of a constant number density. Ellipsoids farther from the LMC center are less elongated and slightly rotated toward the SMC. The inclination and position angle change significantly with the $a$ axis size. The median axis ratio is 1:1.23:1.45. The RR Lyr distribution in the SMC has a very regular, ellipsoidal shape and does not show any substructures or asymmetries. All triaxial ellipsoids fitted to surfaces of a constant number density have virtually the same shape (axis ratio) and are elongated along the line-of-sight. The median axis ratio is 1:1.10:2.13. The inclination angle is very small and thus the position angle is not well defined. We present the distribution of RR Lyr stars in the Magellanic Bridge area, showing that the Magellanic Clouds' halos overlap. A comparison of the distributions of RR Lyr stars and Classical Cepheids shows that the former are significantly more spread and distributed regularly, while the latter are very clumped and form several distinct substructures.

17

OGLE-ing the Magellanic System: Three-Dimensional Structure of the Clouds and the Bridge Using Classical Cepheids

Jacyszyn-Dobrzeniecka A. M., Skowron D. M., Mróz P., Skowron J., Soszyński I., Udalski A., Pietrukowicz P., Kozłowski S., Wyrzykowski Ł., Poleski R., Pawlak M., Szymański M. K., Ulaczyk K.

Acta Astronomica

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2016

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Vol. 66, No. 2

149--196

EN

We analyzed a sample of 9418 fundamental-mode and first-overtone classical Cepheids from the OGLE-IV Collection of Classical Cepheids. The distance to each Cepheid was calculated using the period-luminosity relation for the Wesenheit magnitude, fitted to our data. The classical Cepheids in the LMC are situated mainly in the bar and in the northern arm. The eastern part of the LMC is closer to us and the plane fit to the whole LMC sample yields the inclination i=24.°2 ±0.°7 and position angle P.A.=151.°4±1.°7. We redefined the LMC bar by extending it in the western direction and found no offset from the plane of the LMC contrary to previous studies. On the other hand, we found that the northern arm is offset from a plane by about -0.5 kpc, which was not observed before. The age distribution of the LMC Cepheids shows one maximum at about 100 Myr. We demonstrate that the SMC has a non-planar structure and can be described as an extended ellipsoid. We identified two large ellipsoidal off-axis structures in the SMC. The northern one is located closer to us and is younger, while the south-western is farther and older. The age distribution of the SMC Cepheids is bimodal with one maximum at 110 Myr, and another one at 220 Myr. Younger stars are located in the closer part of this galaxy while older ones are more distant. We classified nine Cepheids from our sample as Magellanic Bridge objects. These Cepheids show a large spread in three-dimensions although five of them form a connection between the Clouds. The closest one is closer than any of the LMC Cepheids, while the farthest one - farther than any SMC Cepheid. All but one Cepheids in the Magellanic Bridge are younger than 300 Myr. The oldest one can be associated with the SMC Wing.

18

The Study of Triple Systems V949 Cen, V358 Pup and V1055 Sco

Zasche P., Hoňkovà K., Juryšek J., Mašek M.

Acta Astronomica

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2015

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Vol. 65, No. 2

151--168

EN

The systems V949 Cen, V358 Pup, and V1055 Sco are triples comprised of an eclipsing binary orbiting with a distant visual component on a much longer orbit. The first detailed photometric analysis of these interesting systems was performed using also the archival data from Hipparcos, ASAS, SuperWASP, OMC, and Pi of the Sky surveys. The system V358 Pup was also analyzed using the archival ESO spectra and the radial velocities were derived. The analyses of their light curves revealed the physical properties of the eclipsing components, while the interferometric data for these systems obtained during the last century show that the binaries are also weakly gravitationally bounded with the third components on much longer orbits. The photometry was carried out with the robotic telescope FRAM (part of the Pierre Auger Cosmic Ray Observatory), located in Argentina. The BVRI light curves were analyzed with the PHOEBE program, yielding the basic physical parameters of the systems and their orbits. V949 Cen and V358 Pup were found to be detached systems, while V1055 Sco is probably a semi-detached one. V358 Pup shows a slow apsidal motion, while for V1055 Sco we detected some period variation probably due to the third body in the system, which cannot easily be attributed to the close visual companion. Therefore, we speculate that V1055 Sco can be a quadruple system. For V949 Cen a new orbit was computed, having the orbital period of about 855 yr.

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BVR Photometric Analysis of GSC 4277-0586 and GSC 3152-1202

Bulut İ., Bulut A.

Acta Astronomica

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2015

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Vol. 65, No. 1

127--138

EN

A detailed light curve analysis of the newly discovered eccentric orbit eclipsing binaries GSC 277-0586 and GSC 3152-1202 are presented for the fist time. For both systems, the B, V and R light curves were secured and also new minima times have been derived. The analysis was made using the Wilson-Devinney program. The absolute dimensions were calculated using mass-luminosity relation for main sequence stars. The O-C diagram of GSC 3152-1202 was also analyzed using all reliable times of minima and the elements of apsidal motion were computed. The apsidal motion period has been found to be 36.6±9.8 years.

20

The Study of Triple Systems V819 Her, V2388 Oph, and V1031 Ori

Zasche P., Uhlàř R., Svoboda P.

Acta Astronomica

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2014

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Vol. 64, No. 2

125--150

EN

The systems V819 Her, V2388 Oph, and V1031 Ori are triples comprised of an eclipsing binary orbiting with a distant visual component on a longer orbit. A detailed analysis of these interesting systems, combining the two observational techniques: interferometry and apparent period variation, was performed. The interferometric data for these three systems obtained during the last century determine the visual orbits of the distant components in the systems. The combined analysis of the positional measurements together with the analysis of apparent period changes of the eclipsing binary (using the minima timings) can be used to study these systems in a combined approach, resulting in a set of parameters otherwise unobtainable without the radial velocities. The main advantage of the technique presented here is the fact that one needs no spectroscopic monitoring of the visual orbits, which have rather long periods: 5.5 yr for V819 Her, 9.0 yr for V2388 Oph, and 31.3 yr for V1031 Ori, respectively. The eccentricities of the outer orbits are 0.69, 0.33, and 0.92, respectively. Moreover, the use of minima timings of the eclipsing pairs helps us to derive the orientation of the orbit in space with no ambiguity around the celestial plane. And finally, the combined analysis yielded also an independent determination of the distance of V819 Her (68.7±1.8 pc), and V2388 Oph (70.6±8.9 pc). We also present a list of similar systems, which would be suitable for a combined analysis like this one.