ONE-DIMENSIONAL SPECTRA OF TURBULENCE-INDUCED ZERNIKE ABERRATIONS - TIME-DELAY AND ISOPLANICITY ERROR IN PARTIAL ADAPTIVE COMPENSATION

A simple derivation is given for the expression of one-dimensional spe ctra of turbulence-induced Zernike aberration terms in the case of a s tellar source at infinity. Numerical results are presented for several terms. Expressions are given for the maximum acceptable delay and the maximum isoplanatic angle in a partially compensating adaptive optics system. Temporal-frequency spectra of the Zernike terms, recorded at the Canada-France-Hawaii telescope, are well reproduced when one convo lves all the corresponding theoretical spectra with the same turbulenc e distribution. Only a few atmospheric layers are found to contribute to image degradation.