Adaptive Optics for Extremely Large Telescopes 4 – Conference Proceedings

ARGOS is the Ground Layer Adaptive Optics system of the Large Binocular Telescope, on each side it uses three Laser Guide Stars, generated by Rayleigh backscattered light of pulsed lasers. Three Shack-Hartmann WFS are used to measure the wavefront distortion in the Ground Layer. The SLOpe Detection And Ranging (SLODAR) is a technique used to measure the atmospheric turbulence profiles. Cross correlation of wavefronts gradients from multiple stars are used to estimate the relative strength of turbulent layers at different altitudes. We present here the first results obteined on sky of appling the SLODAR technique to ARGOS comparing then with a previous study based on end-to-end simulations.