76 measurement sequences were done on a dummy mirror inside the rotating enclosure of the NTT at La Silla. The table gives the azimuth angle with respect to the wind direction, the zenith angle , the position of the wind screen (d - down, u - up), the status of the flaps (o - open, c - closed), the average external wind speed in m/s, the average of the rms
of the pressure variations over the sensors in Pa (after quadratic subtraction of the noise of 1.5 Pa), and the rms of the wavefront aberration computed from the pressure distributions, scaled to the size of the VLT mirror (8.2-m).
NTT
NTT