A procedure has been developed to compute static aberrations after the PSF measured with the lucky imaging technique, using a nearby star as the point source to probe the optical system. This PSF is iteratively turned into a phase map at the pupil using the Gerchberg-Saxton algorithm, and then converted to the adequate actuation information for a

We discuss some recent integral field spectroscopy using the SAURON instrument of a sample consisting of 24 early-type spirals, part of the SAURON Survey, and 18 late-type spirals. Using 2-dimensional maps of their stellar radial velocity, velocity dispersion, and absorption line strength, it is now much easier to understand the nature of nearby

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Feedback from star formation is thought to play a key role in the formation and evolution of galaxies, but its implementation in cosmological simulations is currently hampered by a lack of numerical resolution. We present and test a subgrid recipe to model feedback from massive stars in cosmological smoothed particle hydrodynamics simulations. The

We have observed with continuous photometry some hydrogen-deficient Planetary Nebula Nuclei (PNNs) with bipolar envelopes to search for pulsations, and to characterize the pulsations found. Our sample includes the "hybrid PG 1159" stars Abell 43 and NGC 7094 which are shown to have extremely long period g-mode pulsations between 38 and 101 min

We present the work developed within the science team of the Very Large Telescope Interferometer Spectro-Imager (VSI) during the Phase A studies. VSI aims at delivering ~ 1 milliarcsecond resolution data cubes in the near-infrared, with several spectral resolutions up to 12 000, by combining up to 8 VLTI telescopes. In the design of an instrument