Nuclear rings are in most cases thought to be by-products of gas shock-focusing at Inner Lindblad Resonances (ILRs). AINUR (Atlas of Images of NUclear Rings) is an Atlas which includes images and metric measurements of all 109 known nuclear rings. This Atlas has been produced by checking and processing Hubble Space Telescope archive data from a

We present high-resolution spectroscopic measurements of the abundances of the α element titanium (Ti) and s-process elements yttrium (Y) and lanthanum (La) for 59 candidate M giant members of the Sagittarius (Sgr) dwarf spheroidal (dSph) + tidal tail system pre-selected on the basis of position and radial velocity (RV). As expected, the majority

Deriving the azimuthally averaged radial surface brightness profile of a galaxy is a schematic way of presenting the light and then the mass structure of disc galaxies. In this overview we will dwell on the outer discs, as it has become possible, with modern data to explore the light profile out to ever increasing galactocentric radii. We find that

We have investigated the physics of flares in M-dwarfs by means of optical/X-ray observations and modeling. The great efficiency of current optical spectrographs and detectors has allowed us to detect and analyze a great number of non white-light flares with intermediate spectral resolution and high temporal resolution. Although this kind of flares

High resolution solar images in the near UV have been obtained with the Solar UV Filtergraph (SUFI) onboard the Sunrise balloon borne observatory, amongst others in wavelength regions not accessible from the ground. We present intensity distributions of the quiet Sun at different heliocentric angles, from disk center to the solar limb. These

The excitation and temporal evolution of fast and Alfvén magnetohydrodynamic oscillations in a two-dimensional coronal arcade are investigated. The approach is to consider an equilibrium magnetic and plasma structure and then to introduce a perturbation trying to mimic a nearby disturbance, such as a flare or filament eruption. By numerically