Three radio cm sources in the central star-forming kpc of the closeby barred Seyfert galaxy NGC 1365 are observed. The complete dataset includes VLT infrared J, K, L and N images and spectra. The main observed features include (i) a rising dust continuum towards the mid-infrared (MIR), (ii) bright H emission lines and PAH (polycyclic aromatic hydrocarbon) features, (iii) a bright MIR [Neii] line, and (iv) no detection of MIR [Siv] or [Ariii] lines. For a typical cluster star-formation history and initial mass function, the [Ariii]/[Neii] and [Siv]/[Neii] ratios exhibit an abrupt decrease of several orders of magnitude at an age of ~ 7 Myr. The nondetection of [Ariii] and [Siv] indicates that the clusters are of approximately this age.

We report on the recent developments of our long-term investigation of the near-IR luminosity-metallicity relation for dwarf irregular galaxies in nearby groups. A very well-defined relation is emerging from our observational database, and a preliminary discussion of its implications is given.

We provide an overview of a high spatial resolution study of the molecular emission (H2 and CO) in the few central arcsec region around the AGN in NGC1068. A 0.5″ resolution H2 2.12 μm line map obtained with VLT/ISAAC is presented and reveals interesting characteristics: two unequally bright knots located at 1″ (70 pc) from the nucleus, along a direction perpendicular to the ionizing cone axis. We propose a model involving differential extinction, produced in the emitting molecular disc itself, to explain the intensity difference between the two knots. This effect can arise from a simple configuration, in which the orientation of the molecular disc is slightly tilted with respect to that of the central Compton thick absorber, which blocks the X-rays along our line of sight.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present a set of star cluster integrated spectra based on observations from the ultraviolet to the near-infrared. Mean template spectra were built following a ranking of clusters according to age and metallicity, which were taken from recent studies and put on consistent scales. The complete spectral database including star clusters, galaxies and stars (templates and individuals) is available through the CDS.

As the closest Seyfert nucleus, NGC 1068 is a key object to establish on firm grounds the model of active galactic nuclei (AGN). Two important questions relative to AGNs are : i) can we actually see the parsec-scale torus of dust and molecular gas around the central engine predicted by the popular Unified Model model (e.g. Antonucci, 1993)?; ii) how the gas is brought down to the parsec scale to feed the monster, and, in particular, is there a micro spiral/bar system that could produce the required torque ? Adaptive Optics in the near-IR has potential advantages to make a significant progress in those two questions : the low dust opacity and the excellent angular resolution.

Population synthesis is a powerful tool to study stellar populations where the analysis of the stellar content of a composite system is based on the results of breaking down into components (of a given base) the spectrum of the observed system. Such process constitutes an inverse problem which can have a multitude of possible or “acceptable” solutions. This degenerative character of the synthesis rises mainly from observable errors and from the base of components itself with respect to its internal consistency and its (in)capacity to fully embrace all the free parameters involved.

This paper is aimed at providing a review of recent observational facts regarding blue compact galaxies. Tightening together flux measurements from the UV to the radio range now allow us to draw a somewhat improved, more self-consistent picture of these objects. Many questions are still open however, about their nature and evolution.