We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and a recent reanalysis of Type Ia supernova (SN) data. In particular, we take advantage of high-precision BAO measurements from galaxy clustering and the

Galactic globular clusters (GCs) are known to host multiple stellar populations: a first generation (FG) with a chemical pattern typical of halo field stars and a second generation (SG) enriched in Na and Al and depleted in O and Mg. Both stellar generations are found at different evolutionary stages (e.g., the main-sequence turnoff, the subgiant

Aims: We aim at constraining evolutionary models at low mass and young ages by identifying interesting transiting system members of the nearest OB association to the Sun, Upper Scorpius (USco), which has been targeted by the Kepler mission. Methods: We produced light curves for M-dwarf members of the USco region that has been surveyed during the

We study the population of asymptotic giant branch (AGB) stars in the Small Magellanic Cloud (SMC) by means of full evolutionary models of stars of mass 1 M⊙ ≤ M ≤ 8 M⊙, evolved through the thermally pulsing phase. The models also account for dust production in the circumstellar envelope. We compare Spitzer infrared colours with results from

We present an analysis of the nuclear infrared (IR, 1.6-18 μm) emission of the ultraluminous IR galaxy UGC 5101 to derive the properties of its active galactic nucleus (AGN) and its obscuring material. We use new mid-IR high angular resolution (0.3-0.5 arcsec) imaging using the Si-2 filter (λC = 8.7 μm) and 7.5-13 μm spectroscopy taken with

The solar atmosphere has been studied for decades by means of observations, theory and numerical simulations. However, due to its complexity, it is difficult to fully understand all the phenomena taking place in the atmosphere. Starting from the photosphere up to the corona, the solar atmosphere is strongly stratified and the magnetic fields