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We present new spectroscopic observations of the early type, double-lined eclipsing binary V1441,Aql. The radial velocities and the available photometric data obtained by $ASAS$ is analysed for deriving the parameters of the components. The components of V1441,Aql are shown to be a B3,IV primary with a mass M$_p$=8.02$pm$0.51 M$_{odot}$ and radius R$_p$=7.33$pm$0.19 R$_{odot}$ and a B9 III secondary with a mass M$_s$=1.92$pm$0.14 M$_{odot}$ and radius R$_s$=4.22$pm$0.11 R$_{odot}$. Our analyses show that V1441,Aql is a double-contact system with rapidly rotating components. Based on the position of the components plotted on the theoretical Hertzsprung-Russell diagram, we estimate that the ages of V1441,Aql is about 30,Myr, neglecting the effects of mass exchange between the components. Using the UBVJHK magnitudes and interstellar absorption we estimated the mean distance to the system V1441,Aql as 550$pm$25,pc.
We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the eclipsing
We present the analysis of photometric and spectroscopic data of two classical Cepheids, FN Aquilae and V1344 Aquilae. Based on the joint treatment of the new and earlier radial velocity data, both Galactic Cepheids have been found to be a member in
The first photometric analysis of V811 Cep was carried out. The first complete light curves of V, R and I bands are given. The analysis was carried out by Wilson-Devinney (W-D) program, and the results show that V811 Cep is a median-contact binary ($
Eclipsing binary DI Herculis (DI Her) is known to exhibit anomalously slow apsidal precession, below the rate predicted by the general relativity. Recent measurements of the Rossiter-McLauglin effect indicate that stellar spins in DI Her are almost o
We have carried out a spectroscopic variability survey of some of the most massive stars in the Arches cluster, using K-band observations obtained with SINFONI on the VLT. One target, F2, exhibits substantial changes in radial velocity; in combinatio