We analyzed seven, target ID 31686, Swift follow-up observations of the neutron-star X-ray transient Swfit J1749.4-2807 (Wijnands et al. 2009) currently in outburst and which was found to be an accreting millisecond X-ray pulsar (ATel #2565). The observations span from April 11 to April 20.

At high-z the most superdense massive galaxies are supposed to be the result of gas-rich mergers resulting in compact remnant (Khochfar & Silk (2006); Naab et al. (2007)). After this, dry mergers are expected to be the mechanism that moves these very massive galaxies towards the current stellar mass size relation. Whitin these merging scenarios, a

We present extensive photometric and spectroscopic study to give a new insight in the bulge stellar population. Super-solar α/Fe and its constant value along the radial profile, in most of the galaxies, suggest that the star formation in these objects has been fast and occurred at the same time in the whole bulge.

The goal of this work is to determine the properties of the stellar populations in a sample of LIRGs and ULIRGs. Using the ages as a clock we investigate: a) whether LIRGs-ULIRGs evolve into Radio Galaxies and QSOs; b) whether cool LIRGs-ULIRGs can evolve into warm LIRGs-ULIRGs; c) the merger sequence deduced from the morphological studies is

We present the results of an investigation of a large sample of brightest cluster galaxies (BCGs), their kinematic and stellar population properties and the relationships between these and the properties of the host clusters. We have obtained high signal-to-noise, long-slit spectra of 49 BCGs in the nearby Universe with the Gemini and WHT

A full understanding of the physical properties of integrated stellar systems demands a multiwavelength approach since each spectral window shows us the contribution of different types of stars. However, most of the observational effort in stellar population studies has been focused on the optical range. Now, the new generation of instruments allow