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We present deep color-magnitud diagrams (CMDs) reaching the oldest main-sequence turnoffs for 12 fields in the SMC. The {it B}-band and {it R}-band observations were performed using the 100-inch Irenee du Pont telescope at Las Campanas Observatory, Chile, during four different campaigns (2001-2004). Our fields cover a wide range of galactocentric distance ranging from $sim1deg$ to $sim4deg$ from the center of the galaxy and are located a different position angles. Photometry was carried out using DAOPHOT II/ALLSTAR/ALLFRAME. Teramo isochrones have been overlapped. All our unprecedented deep ground-based CMDs reach the old MS turnoffs with very good photometric accuracy. They clearly show stellar population gradients as a function of both galactocentric distance and position angle. The most conspicuous difference involves the young population (age$<$1 Gyr): the young MS is much more populated on the eastern fields, located on the SMC wing area, than on the western fields located at similar galactocentric radius. In addition, the main stellar population gets progresively older on average as we go to larger galactocentric radius.
This is a summary of my lectures during the 2011 IAC Winter School in Puerto de la Cruz. I give an introduction to the field of stellar populations in galaxies, and highlight some new results. Since the title of the Winter School was {it Secular Evol
The vast volume of data generated by modern astronomical surveys offers test beds for the application of machine-learning. It is important to evaluate potential existing tools and determine those that are optimal for extracting scientific knowledge f
We present near infrared JHK imaging of the Small Magellanic Cloud compact H II region N81 using the ISAAC camera at the ESO Very Large Telescope (Antu). Our analysis of the stellar environment of this young massive star region reveals the presence o
Studying the stellar populations in the outskirts of spiral galaxies can provide important constraints on their structure, formation, and evolution. To that end, we present VI photometry obtained with the Advanced Camera for Surveys for three fields
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here we reeval