High-Spatial Resolution Imaging Combining High-Order Adaptive Optics, Frame Selection, and Speckle Masking Reconstruction

Abstract. We present, for the first time, high-spatial resolution observations combining high-order adaptive optics (AO), frame selection, and post-facto image correction via speckle masking. The data analysis is based on observations of solar active region NOAA 10486 taken with the Dunn Solar Tele-scope (DST) at the Sacramento Peak Observatory (SPO) of the National Solar Observatory (NSO) on 2003 October 29. The high Strehl-ratio encountered in AO corrected short-exposure images provides highly improved signal-to-noise ratios leading to a superior recovery of the object’s Fourier phases. This allows reliable detection of small-scale solar features near the diffraction limit of the telescope. Speckle masking imaging provides access to high-order wavefront abberations, which predominantly originate at high atmospheric layers and are only partially corrected by the high-order AO system. In addition, the observations provided qualitative measures of the image correction away from the lock point of the AO system. We further present a brief inspection of the underlying imaging theory discussing the limitations and prospects of this multi-facetted image reconstruction approach in terms of the recovery of spatial information, photometric accuracy, and spectroscopic applications