For a number of reasons, the properties of integrated stellar populations are distributed. Traditional synthesis models usually return the mean value of such distribution, and a perfect fitting to observational data is sought for to infer the age and metallicity of observed stellar populations. We show here that, while this is correct on average

Colour-magnitude diagrams in the Washington system are presented for the first time for five star clusters projected on to the outer region of the Small Magellanic Cloud (SMC). The clusters are found to have ages in the range 0.1-1.0 Gyr, as derived from the fit of isochrones with Z = 0.004. This sample increases substantially the number of young

In this paper we present the photometric properties of a sample of extremely red galaxies (EROs, R-Ks≥5.6), found in the field of the lensing cluster Abell 1835. Using optical, near- and mid-infrared colours, we compare our ERO sample with other galaxy populations with extreme colours, like distant red galaxies (DRGs, J-Ks≥2.3) and infrared

Not Available

Aims:The role of longitudinal structuring of the surrounding corona on the modes of oscillation of a coronal magnetic flux tube was studied in Donnelly et al. (2006) for a piecewise uniform profile. Here we investigate whether a more realistic continuous exponential profile changes the conclusions drawn from that paper. Methods: A partial

Division II provides a forum for astronomers studying a wide range of problems related to the structure, radiation and activity of the Sun, and its interaction with the Earth and the rest of the solar system.