A comparative analysis is performed between high-quality integrated spectral indices of 30 M31 globular clusters, 20 Milky Way globular clusters, and a sample of field and cluster elliptical galaxies. We find that the Lick CN indices in the M31 and Galactic clusters are enhanced relative to the bulges of the Milky Way, M31, and elliptical spheroids

We present a high-quality color-magnitude diagram (CMD) for a 36'×36' field located 8° (~=7 kpc) from the Large Magellanic Cloud (LMC) center, as well as a precise determination of the LMC surface brightness derived from the resolved stellar population out to this large galactocentric radius. This deep CMD shows for the first time the detailed age

Models for superbursts from neutron stars involving carbon shell flashes predict that the mass accretion rate should be anywhere in excess of one tenth of the Eddington limit. Yet, superbursts have so far only been detected in systems for which the accretion rate is derived to be between 0.1 and 0.25 times that limit. The question arises whether

SUNRISE is a balloon-borne solar telescope with an aperture of 1m, working in the UV/VIS optical domain. The main scientific goal of SUNRISE is to understand the structure and dynamics of the magnetic field in the atmosphere of the Sun. SUNRISE will provide diffraction-limited images of the photosphere and chromosphere with an unpredecented

We present near infrared (J, H and Ks) observations of a 5'× 10' sample field in the Serpens Star Formation region obtained with SOFI at the NTT. These observations are sensitive enough to detect a 20 MJup brown dwarf through an extinction of AV˜ 16 and are used to build an infrared census of this field in the cluster. From photometry and mass

We are carrying out a project for studying all the Second Byurakan Survey (SBS) interacting systems of galaxies at z 0.1. The objectives of this project are: (1) to link the histories of the star formation and nuclear activity in these systems with the morphologic type of the interacting galaxies; (2) to settle upper limits to the age of the