We have investigated the dynamical interaction of low- and intermediate-mass stars (from 1 to 5 Msolar) with their interstellar medium (ISM). In this first paper, we examine the structures generated by the stellar winds during the asymptotic giant branch (AGB) phase using a numerical code and the wind history predicted by stellar evolution. The

With a sample of 17 delta Scuti stars belonging to 5 young open clusters, we study correlations between fundamental parameters and the oscillation amplitude. The results published in a paper recently accepted by A and A show a significant correlation between the parameter i´(estimation of the angle of inclination of the star) and the oscillation

We present high-resolution Very Large Telescope/Ultraviolet Visual Echelle Spectrograph observations of 56 stars in the extended horizontal-branch (EHB) of the Galactic globular clusters NGC 1904, NGC 2808, NGC 6093, and NGC 7078. Our data reveal for the first time the presence in NGC 1904 of a sizable population of fast (vsini>=20 km s-1)

We present VR observations of QSO 2237+0305 conducted by the Gravitational Lensing International Time Project collaboration from 1999 October 1 to 2000 February 3. The observations were made with the 2.56 m Nordic Optical Telescope at Roque de los Muchachos Observatory, La Palma (Spain). The point-spread function (PSF) fitting method and an adapted

We use long-slit spectroscopy along the major axis of a sample of 23 nearby disk galaxies to study the kinematic properties of the ionized-gas component in their inner regions. For each galaxy, we derive the position-velocity diagram of the ionized gas from its emission lines. We discuss the variety of shapes observed in such position-velocity

This Letter presents wide-field optical and near-IR (UBVRIHαK') images of the galaxy M74 that were taken between 0.6 and 8.3 yr before the discovery of the Type Ic supernova 2002ap. We have located the position of the supernova on these images with an accuracy of 0.3". We find no sign of a progenitor object on any of the images. The deepest of