We present optical integral field spectroscopy analysis of the main components, with the exception of the halo, as well as of the detected small-scale structures of the planetary nebulae NGC 3242. The observations were obtained with the VIMOS instrument attached to VLT-UT3. Spatially resolved maps of the electronic density (N e), temperatures (T e)

We have derived masses and radii for both components in five short-period single-lined eclipsing binary stars discovered by the TrES wide-angle photometric survey for transiting planets. All these systems consist of a visible F-star primary and an unseen M-star secondary (M A >= 0.8 M sun, M B

Spectroscopic and photometric observations are used to determine the distributions of gas and the kinematics in the central zones of a number of spirals. In addition to a ring structure in the gas, there is often found a measurable expansion with high radial velocity near the nucleus. A significant correlation is noted between the absence of

Chromospheric model calculations of the Hα line for selected red giant branch and asymptotic giant branch (AGB) stars in the globular clusters M13, M15, and M92 are constructed to derive mass loss rates (MLRs). The model spectra are compared to the observations obtained with the Hectochelle on the MMT telescope. These stars show strong Hα emissions

The best-fitting two-dimensional plane within the three-dimensional space of spiral galaxy disc observables (rotational velocity vrot, central disc surface brightness μ0=-2.5logI0 and disc scalelength h) has been constructed. Applying the three-dimensional bisector method of regression analysis to a sample of ~100 spiral galaxy discs that span more

We present the first results of a project aimed at the combined study of massive stars and their surrounding nebulae by means of a detailed study of Galactic H II regions ionized by only one massive star. With this, we intend to check the validity of the new generation of massive star model atmosphere codes in terms of ionizing flux distribution