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The present work concerns the Asteroseismology of the Kepler detached eclipsing binary KIC 8504570. Particularly, it focuses on the pulsational behaviour of the oscillating component of this system and the estimation of its physical parameters in order to enrich the so far poor sample of this kind of systems. Using spectroscopic observations, the spectral type of the primary component was determined and used to create accurate light curves models and estimate its absolute parameters. The light curve residuals were subsequently analysed using Fourier transformation techniques to obtain the pulsation models. Theoretical models of $\delta$ Scuti stars were employed to identify the oscillation modes of the six detected independent frequencies of the pulsator. In addition, more than 385 combination frequencies were also detected. The absolute and the pulsational properties of the $\delta$ Scuti star of this system are discussed and compared with all the currently known similar cases. Moreover, using a recent (empirical) luminosity-pulsation period relationship for $\delta$ Scuti stars, the distance of the system was estimated., Comment: 26 pages, 12 figures, accepted for publication in Galaxies in the special issue "Astrophysics of Eclipsing Binaries in the Era of Space-Borne Telescopes"

The catalogue contains 199 confirmed cases of binary systems containing at least one pulsating component of {\delta} Scuti type. The sample is divided into subgroups in order to describe the properties and characteristics of the {\delta} Sct type stars in binaries according to their Roche geometry. Demographics describing quantitatively our knowledge for these systems as well as the distributions of their pulsating components in the Mass-Radius, Colour-Magnitude and Evolutionary Status-Temperature diagrams are presented and discussed. It is shown that a threshold of ~13 days of the orbital period regarding the influence of binarity on the pulsations is established. Finally, the correlations between the pulsation periods and the orbital periods, evolutionary status, and companion's gravity influence are updated based on the largest sample to date., Comment: 20 pages, 12 figures, 5 tables

The results of our six year systematic observational survey on candidate eclipsing binaries with a delta Sct component are briefly presented. A new catalogue for this kind of systems as well as the properties of their delta Sct members are also presented. The comparison between the components-pulsators and the single delta Sct stars shows that both the evolution and the pulsating properties differ significantly. Finally, we introduce the new era of studying stellar pulsations using high accuracy data from Kepler mission and emphasizing the great opportunities that are now opened for a deep knowledge of the properties of stellar pulsations., Comment: 4 pages, 6 figures, Proceedings of the 12th Hellenic Astronomical Conference, held 28 June - 2 July, 2015 in Thessaloniki, Greece

Results from a six year systematic observational survey on candidate eclipsing binaries with a $\delta$ delta Sct component are presented. More than a hundred systems with component(s) of A-F spectral types were observed in the frame of this survey in order to be checked for possible pulsational behaviour. The 14% (13 cases) of the currently known such systems were discovered during this survey. Using all the available information from the literature, an updated list with all the currently known systems of this type is presented, while possible correlations between their pulsational and binarity properties are discussed., Comment: 5 pages, 5 figures, 1 table, Proceedings of the international conference: Living Together: Planets, Stellar Binaries and Stars with Planets, 8-12 September 2014, Litomy\v{s}l, Czech Republic

CCD observations of 68 eclipsing binary systems, candidates for containing {\delta} Scuti components, were obtained. Their light curves are analysed using the PERIOD04 software for possible pulsational behaviour. For the systems QY Aql, CZ Aqr, TY Cap, WY Cet, UW Cyg, HL Dra, HZ Dra, AU Lac, CL Lyn and IO UMa, complete light curves were observed due to the detection of a pulsating component. All of them, except QY Aql and IO UMa, are analysed with modern astronomical softwares in order to determine their geometrical and pulsational characteristics. Spectroscopic observations of WY Cet and UW Cyg were used to estimate the spectral class of their primary components, while for HZ Dra radial velocities of its primary were measured. O - C diagram analysis was performed for the cases showing peculiar orbital period variations, namely CZ Aqr, TY Cap, WY Cet and UW Cyg, with the aim of obtaining a comprehensive picture of these systems. An updated catalogue of 74 close binaries including a {\delta} Scuti companion is presented. Moreover, a connection between orbital and pulsation periods, as well as a correlation between evolutionary status and dominant pulsation frequency for these systems, is discussed., Comment: 13 pages, 22 figures, 8 tables

CCD multi-band light curves of the neglected eclipsing binaries V405 Cep, V948 Her, KR Mon and UZ Sge were obtained and analysed using the Wilson-Devinney code. New geometric and absolute parameters were derived and used to determine their current evolutionary state. V405 Cep, V948 Her and KR Mon are detached systems with their components in almost the same evolutionary stage. UZ Sge is a classical Algol system with a tertiary companion around it. Moreover, since the systems V405 Cep, V948 Her and UZ Sge contain an early type component, their light curves were examined for possible pulsation behaviour., Comment: 9 pages, 14 figures, 4 tables

New CCD light curves of the recently detected eclipsing variable GSC 4589-2999 were obtained and analysed using the Wilson-Deninney code. Spectroscopic observations of the system allowed the spectral classification of the components and the determination of their radial velocities. The physical properties and absolute parameters of the components and an updated ephemeris of the system are given., Comment: 5 pages, 9 figures, 5 tables

Aims: We aim to derive the absolute parameters of the components of AD And, AL Cam, and V338 Her, interpret their orbital period changes and discuss their evolutionary status. Methods: New and complete multi-filter light curves of the eclipsing binaries AD And, AL Cam, and V338 Her were obtained and analysed with modern methods. Using all reliably observed times of minimum light, we examined orbital period irregularities using the least squares method. In addition, we acquired new spectroscopic observations during the secondary eclipses for AL Cam and V338 Her. Results: For AL Cam and V338 Her, we derive reliable spectral types for their primary stars. Statistical checks of orbital period analysis for all systems are very reassuring in the cases of V338 Her and AD And, although less so for AL Cam. The LIght-Time Effect (LITE) results are checked by inclusion of a third light option in the photometric analyses. Light curve solutions provide the means to calculate the absolute parameters of the components of the systems and reliably estimate their present evolutionary status. Conclusions: AL Cam and V338 Her are confirmed as classical Algols of relatively low mass in similar configurations. Unlike AL Cam, however, V338 Her is still transferring matter between its components, raising interest in the determinability of the evolutionary histories of Algols. AD And is found to be a detached system in which both close stars are of age ~109 yr and is probably a "non-classical" young triple, at an interesting stage of its dynamical evolution., Comment: 9 pages, 12 figures, 4 tables

CCD light curves of the Algol type eclipsing binaries DP Cep, AL Gem, FG Gem, UU Leo, CF Tau and AW Vul were analysed using the Wilson-Deninney code and new geometric and absolute parameters were derived. Due to cyclic apparent orbital period changes of the systems, probably caused by the Light-Time Effect, the contribution of a third light was taken into account in the light curve solution. All the reliable timings of minima found in the literature were used to study the period variations and search for the presence of a tertiary component in the systems. A comparison between the parameters of the third body derived from the light curve and orbital period analyses is also discussed. Moreover, the absolute parameters of the eclipsing binary components were also used to determine their current evolutionary state., Comment: 14 pages, 13 figures, 5 tables

New BVRI CCD photometric observations of the contact system DF Hya have been obtained. The light curves were analyzed with the Wilson-Devinney code and new geometric and photometric elements were derived. Moreover, the light curve solution, with the assumption of a third light in the system, revealed the existence of a tertiary component around the eclipsing pair. The present results are compared with those of other recent studies., Comment: 2 pages, 2 figures, Proceedings of the 10th Hellenic Astronomical Conference, held at Ioannina, Greece, 5-8 September 2011

New BVRI CCD observations of the semi-detached eclipsing binary EG Cep are presented. The observed light curves are analyzed with the Wilson-Devinney program and new geometrical and photometric elements are derived. These elements are used to compute the physical parameters of the system in order to study its evolutionary status., Comment: 4 pages, 2 figures, contribution to the conference proceedings: 5th SREAC's meeting: Latest progess in Astrophysics, Athens, Hellas, 5-6 Oct.2007

New BVRI light curves of the system V1464 Aql (ellipsoidal variable with a delta Scuti component) were obtained. Using these observations and taking into account previous studies of the system, its light curve model was reproduced and the pulsation frequencies of the delta Scuti component were recalculated. Moreover, the derived parameters were used to estimate the evolutionary status of both components., Comment: 2 pages, 3 figures, 2 tables, Proceedings of the 11th Hellenic Astronomical Conference, held 8-12 September, 2013 in Athens, Greece

New times of minima of the eclipsing binaries GK Cep and VY Cet, obtained at the Observatory of the University of Athens, have been used together with all reliable timings found in the literature in order to study the period variation and search for the presence of third body in the systems., Comment: 2 pages, 1 figure, contribution to "First Middle East-Africa, Regional IAU Meeting", held 5-10 April, 2008 in Cairo, Egypt

New complete light and radial velocities curves were obtained for the eclipsing binaries CC Her and CM Lac. The data are analysed with modern techniques in order to derive the physical parameters of the systems and study their present evolutionary status. We found that CC Her is a classical Algol type binary, while CM Lac is a detached system with two Main Sequence stars in asynchronous orbit., Comment: 10 pages, 13 figures

New and complete multi-band light curves of the oEA stars QY Aql, BW Del, TZ Dra, BO Her and RR Lep were obtained and analysed with the Wilson-Devinney code. The light curves residuals were further analysed with the Fourier method in order to derive the pulsation characteristics of the oscillating components. All the reliable observed times of minimum light were used to examine orbital period irregularities. The orbital period analyses revealed secular changes for QY Aql and BW Del, while the Light-Time Effect seems to be the best explanation for the cyclic period changes in TZ Dra and BO Her. RR Lep has a rather steady orbital period. Light curve solutions provided the means to calculate the absolute parameters of the components of the systems, which subsequently were used to make an estimate of their present evolutionary status., Comment: 12 pages, 22 figures

New transit light curves of the third body in the system AV CMi have been obtained. The eclipsing pair's light curves were re-analysed with the W-D code and new absolute elements were derived for the two components. Moreover the new light curves (together with those given by Liakos & Niarchos 2010) of the third body transiting one of the components were analysed with the Photometric Software for Transits (PhoS-T). The results from both analyses are combined with the aim to study the nature of the third component., Comment: 2 pages, 4 figures, contribution to the conference proceedings: IAU Symposium 282 - From Interacting Binaries to Exoplanets: Essential Modeling Tools, Tatransk\'a Lomnica, Slovakia, 18-22 Jul. 2011

CCD photometric observations of the Algol-type eclipsing binary AT Peg have been obtained. The light curves are analyzed with modern techniques and new geometric and photometric elements are derived. A new orbital period analysis of the system, based on the most reliable timings of minima found in the literature, is presented and apparent period modulations are discussed with respect to the Light-Time effect (LITE) and secular changes in the system. The results of these analyses are compared and interpreted in order to obtain a coherent view of the system's behaviour., Comment: 2 pages, 2 figures, contribution to the conference proceedings: IAU Symposium 282 - From Interacting Binaries to Exoplanets: Essential Modeling Tools, Tatransk\'a Lomnica, Slovakia, 18-22 Jul. 2011