Estimating the point spread function of the adaptive optics system ADONIS using the wavefront sensor measurements

Adaptive Optics (AO) has been developed to compensate the wavefront deformation due to the atmo- spheric turbulence. The wavefront correction, however, is often only partial and a residual blur is present in a long exposure image. It is therefore important to deconvolve the image to do accurate photometry or to detect faint structures. For this, the point spread function (PSF) has to be known. The PSF is highly variable in time and dif- cult to calibrate. We developed an algorithm which re- constructs the PSF of the ADONIS AO system from the wavefront sensor measurements. We present the results obtained for dierent observing conditions and discuss the limits of the method. We prove the existence of a local non-stationary turbulence from analyzing the spatial and temporal behaviour of the turbulent phase. We found dif- cult to achieve photometric precision higher than 5 to 10% on secondary components of multiple systems with flux ratio larger than 4.