The vector Apodizing Phase Plate (vAPP) is a class of pupil plane coronagraph that enables high-contrast imaging by modifying the Point Spread Function (PSF) to create a dark hole of deep flux suppression adjacent to the PSF core. Furthermore, from our data, we are able to constrain the mass of any purported companion to Vega to be less than ~45MJ at 8 AU and less than ~30MJ at 16 AU, radii not previously probed at these sensitivities. The highly stable nature of speckles will exist for any program using coronagraphy and high-order AO. However, we are able to improve our dynamic range by 1.5-2 mag through subtraction of static/quasi-static speckles in two rotating frames: the telescope pupil frame and the deformable mirror frame. Because of this, we find that our detection limit is not significantly improved simply with increased exposure time alone. This is due to the fact that the AO system corrects disturbances to the stellar wave front at the level where the instrumental wave front errors dominate. We find the speckle pattern to be highly stable in both position and time in our data. This data set is unique for studying the temporal behavior of speckle noise and represents the first time such a study on highly corrected coronagraphic AO images has been carried out in a quantitative way. We have obtained a series of 284 8 s, AO-corrected, coronagraphically occulted H-band images of the star Vega at the 3.63 m AEOS telescope located on Haleakala, Hawaii. Correlated speckle noise is one of the biggest obstacles limiting such high-contrast imaging. Current instruments employing the combination of adaptive optics (AO) and coronagraphy can typically detect objects within 2'' of the star that are ~104-105 times fainter. The major obstacle to the direct detection of companions to nearby stars is the overwhelming brightness of the host star.
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