Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH). These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3).
View Article and Find Full Text PDFWe have developed a new spectro-gonio radiometer, SHADOWS, to study in the laboratory the bidirectional reflectance distribution function of dark and precious samples. The instrument operates over a wide spectral range from the visible to the near-infrared (350-5000 nm) and is installed in a cold room to operate at a temperature as low as -20°. The high flux monochromatic beam is focused on the sample, resulting in an illumination spot of about 5.
View Article and Find Full Text PDFThe realization and the characterization of the leaky loop integrated Fourier transform spectrometer (LLIFTS) is described. The principle of the LLIFTS lies on a two-beam interferometer in planar design using a leaky loop waveguide structure. The interference pattern is measured at the edge of the component.
View Article and Find Full Text PDFWe propose a new concept of pupil motion sensor for astronomical adaptive optics systems and present experimental results obtained during the first laboratory validation of this concept. Pupil motion is an important issue in the case of extreme adaptive optics, high contrast systems, such as the proposed Planet Finder instruments for the ESO and Gemini 8-meter telescopes. Such high contrast imaging instruments will definitively require pupil stabilization to minimize the effect of quasi-static aberrations.
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