Related papers: Delta Scorpii 2011 periastron: worldwide observati…
We report high-precision observations of the linear polarization of the F1$\,$III star $\theta$ Scorpii. The polarization has a wavelength dependence of the form expected for a rapid rotator, but with an amplitude several times larger than…
The high-precision astrometric mission GAIA recently reported the remarkable discovery of a Sun-like star closely orbiting a dark object, with a semi-major axis and period of $1.4\, \rm{AU}$ and $187.8$ days respectively. While the…
U Sco is a recurrent nova with eleven observed eruptions, most recently in 2010.1 and 2022.4. I report on my program (running since 1989) of measuring eclipse times and brightnesses of U Sco in quiescence, from 2010 to 2022. The orbital…
The first two of a total of six nano-satellites that will constitute the BRITE-Constellation space photometry mission have recently been launched successfully. In preparation for this project, we carried out time-resolved colour photometry…
In this work we propose a preliminary seismic investigation of $\delta$ Scuti stars in the Pleiades cluster, focusing on potential diagnostics of convection and core-overshooting. Taking into account the effect of fast rotation in the…
Period changes of Delta Scuti stars have been collected or redetermined from the available observations and are compared with values computed from evolutionary models with and without convective core overshooting. For the radial pulsators…
We present the first results of an observational project, which addresses the period changing behaviour of a sample of high-amplitude delta Scuti stars. In this paper we discuss the double-mode nature of V567 Ophiuchi. It was observed on 15…
We present new photometric data for seven high-amplitude delta Scuti stars. The observations were acquired between 1996 and 2002, mostly in the Johnson photometric system. For one star (GW UMa), our observations are the first since the…
Belonging to the group of B[e] stars, V921 Scorpii is associated with a strong infrared excess and permitted and forbidden line emission, indicating the presence of low- and high-density circumstellar gas and dust. Many aspects of V921 Sco…
The multi-color CCD photometric study of 27 Delta Scuti stars is presented. By using approximately three years of photometric observations, we obtained the times of maxima and magnitude changes during the observation time interval for each…
Eclipsing binary stars with Delta Scuti components are exceptional systems for gaining a deeper understanding of stellar systems. WY Leo is one such system, exhibiting Delta Scuti-type oscillations. However, it has not been extensively…
Zeta Aquarii is a bright and nearby (28 pc) triple star with a 26-year astrometric subsystem. Almost a half of the outer 540-year visual orbit has been covered in 238 years of its observations. Both inner and outer orbits are revised here…
We present a list of delta Scuti stars in double and multiple systems, ranging from the very wide binaries to the very close ones such as spectroscopic and eclipsing systems including the optical visual pairs which are of no further use…
High-mass binary stars are known to show an unexplained discrepancy between the dynamical masses of the individual components and those predicted by models. In this work, we study Sigma Scorpii, a double-lined spectroscopic binary system…
The mysterious 3rd magnitude long period eclipsing binary star system epsilon Aurigae is predicted to be starting its 2 year eclipse in the late summer of 2009. While this is when the real excitement starts, much is to be learned before…
The very wide double star CCDM 23239-5349 is an interesting study case of a pulsating star within a common origin pair or wide binary. Both stars are located in the Delta Scuti instability strip. Based on data obtained at La Silla (Chile),…
The preliminary results of a multisite photometric campaign on the Pleiades Delta Scuti variable V650 Tauri are reported. The star was observed photometrically for 14 days during 2008 November from three observatories distributed in…
Delta Scuti (delta Sct) stars are opacity-driven pulsators with masses of 1.5-2.5M$_{\odot}$, their pulsations resulting from the varying ionization of helium. In less massive stars such as the Sun, convection transports mass and energy…
The bright southern binary star beta Centauri (HR 5267) has been observed with the Sydney University Stellar Interferometer (SUSI) and spectroscopically with the ESO CAT and Swiss Euler telescopes at La Silla. The interferometric…
Preliminary results on the discovery and follow-up observations of a new $\delta$ Scuti pulsator in the Cygnus field are presented. The variability of the star HD 207331 was detected while testing a Str\"omgren spectrophotometer attached to…