SIMBAD references

We present the results of contemporaneous seeing measurements using a multi-object Shack-Hartmann wavefront sensor, SCIDAR optical turbulence profiling, and a DIMM seeing monitor at the William Herschel Telescope in La Palma. The data are used to determine the accuracy with which angular anisoplanatism can be predicted from generalized SCIDAR turbulence profile measurements. Theoretical predictions of the angular correlation of the Zernike aberration coefficients, based on the SCIDAR profiles, agree with direct measurements from the wavefront sensor to within 7 per cent rms. Estimates of the total seeing (integrated optical turbulence strength) from the methods agree to 10 per cent rms. We conclude that SCIDAR represents a reliable means for calibration of the spatially and temporally variable point-spread function for imaging with adaptive optics in astronomy.