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Analysis of eclipsing binaries containing non-radial pulsators allows i) combining two different and independent sources of information on the internal structure and evolutionary status of the components and ii) studying the effects of tidal forces on pulsations. KIC 3858884 is a bright Kepler target whose light curve shows deep eclipses, complex pulsation patterns with pulsation frequencies typical of δ Sct, and a highly eccentric orbit. We present the result of the analysis of Kepler photometry and of high resolution phaseresolved spectroscopy. Spectroscopy yielded both the radial velocity curves and, after spectral disentangling, the primary-component effective temperature and metallicity, and line-of-sight projected rotational velocities. The Kepler light curve was analyzed with an iterative procedure that was devised to disentangle eclipses from pulsations and takes the visibility of the pulsating star into account during eclipses. The search for the best set of binary parameters was performed by combining the synthetic light curve models with a genetic minimization algorithm, which yielded a robust and accurate determination of the system parameters. The binary components have very similar masses (1.88 and 1.86 M☉) and effective temperatures (6800 and 6600 K), but different radii (3.45 and 3.05 R☉). The comparison with the theoretical models showed a somewhat different evolutionary status of the components and the need to introduce overshooting in the models. The pulsation analysis indicates the hybrid nature of the pulsating (secondary) component, where the corresponding high order g-modes might be excited by an intrinsic mechanism or by tidal forces. [ABSTRACT FROM AUTHOR]

We report the discovery of a multiple system with a quadruple-lined spectrum and a double eclipsing feature. Our photometric and high-resolution spectroscopic data show that V994 Herculis (V994 Her; ADS 11373 AB) is composed of two pairs of double-lined eclipsing binaries, which we designate as A and B. System A consists of a B8V+A0V binary with an orbital period of 2.083 264 d and system B of a A2V+A4V binary with 1.420 033 d. Our light curves show that both of them have a detached binary configuration. We derive masses and radii of four components (Aa, Ab, Ba and Bb) from the synthetic analyses of light curves and radial velocity curves. The masses of systems A and B are and , with radii and , respectively. These masses and radii are well consistent with the empirical relation for double-lined eclipsing binaries. [ABSTRACT FROM AUTHOR]

We have made an asteroseismic analysis of the variable blue stragglers in the open cluster M67. The data set consists of photometric time-series from eight sites using nine 0.6–2.1 m telescopes with a time-baseline of 43 d. In two stars, EW Cnc and EX Cnc, we detect the highest number of frequencies (41 and 26) detected in δ Scuti stars belonging to a stellar cluster, and EW Cnc has the second highest number of frequencies detected in any δ Scuti star. We have computed a grid of pulsation models that take the effects of rotation into account. The distribution of observed and theoretical frequencies shows that in a wide frequency range a significant fraction of the radial and non-radial low-degree modes are excited to detectable amplitudes. Despite the large number of observed frequencies we cannot constrain the fundamental parameters of the stars. To make progress we need to identify the degrees of some of the modes from either multicolour photometry or spectroscopy. [ABSTRACT FROM AUTHOR]