Stellar populations in NGC 5128 with the VLT: Evidence for recent star formation

We resolve stars of the nearest giant elliptical galaxy NGC 5128 using VLT with FORS1 and ISAAC. We construct deep U, V and K-s color-magnitude and co lor-color diagrams in two different halo fields (in the halo and in the nor th-eastern diffuse shell). In the outer, shell field, at similar to 14 kpc from the center of the galaxy, there is a significant recent star formation with stars as young as 10 Myr, approximately aligned with the prominent ra dio and X-ray jet from the nucleus of the host AGN. Ionized gas filaments a re evident in ultraviolet images near the area where neutral Hi and CO mole cular gas was previously observed. The underlying stellar population of the halo of the giant elliptical is predominantly old with a very broad metall icity distribution. The presence of an extended giant branch reaching M-bol = -5 mag suggests the existence of a significant intermediate-age AGB popu lation in the halo of this galaxy.