Non-common path aberrations (NCPA) in an adaptive optics system are static aberrations that appear due to the difference in optical path between light arriving at the wavefront sensor (WFS) and at the science detector. If the adaptive optics are calibrated to output an unaberrated wavefront, then any optics outside the path of the light arriving at the WFS inherently introduce aberrations to this corrected wavefront. NCPA corrections calibrate the adaptive optics system such that it outputs a wavefront that is inverse in phase to the aberrations introduced by these non-common path optics, and therefore arrives unaberrated at the science detector, rather than at the output of the corrective elements. Focal plane sharpening (FPS) is one technique used to calibrate for NCPA in adaptive optics systems. Small changes in shape to the deformable element(s) are implemented and images are taken and analyzed for image quality (IQ) on the science detector. This process is iterated until the image quality is maximized and hence the NCPA are corrected. The work carried out as described in this paper employs two FPS techniques at Gemini North to attempt to mitigate up to 33% of the adaptive optics performance and image quality degradations currently under investigation. Changes in the NCPA correction are made by varying the Zernike polynomial coefficients in the closed-loop correction file for Altair (the facility adaptive optics system). As these coefficients are varied during closed-loop operation, a calibration point-source at the focal plane of the telescope is imaged through Altair and NIRI (the facility near-infrared imager) at f/32 in K-prime (2.12 μm). These images are analyzed to determine the Strehl ratio, and a parabolic fit is used to determine the appropriate coefficient correction that maximizes the Strehl ratio. Historic calibrations of the NCPA file in Altair's control loop were done at night on a celestial point source, and used a separate, high-resolution WFS (with its own inherent aberrations not common to either NIRI nor Altair) to measure phase corrections directly. In this paper it is shown that using FPS on a calibration source negates both the need to use costly time on the night sky and the use of separate optical systems (which introduce their own NCPA) for analysis. An increase of 6% in Strehl ratio is achieved (an improvement over current NCPA corrections of 11%), and discussions of future improvements and extensions of the technique is presented. Furthermore, a potentially unknown problem is uncovered in the form of high spatial frequency degradation in the PSF of the calibration source.

Cycladenia humilis (Apocynaceae) is a rare perennial herb native to western North America and has a fragmented distribution in California, Utah, and Arizona. Populations in Utah and Arizona are federally listed as threatened, while there is no conservation status applied to California populations. Using genetic (three chloroplast and two nuclear DNA loci) and morphological characters, intraspecific variation between populations of C. humilis and current taxonomic conventions were assessed. Nested Clade Phylogeographic Analysis and Bayesian phylogenies were used to assess patterns within C. humilis and supported three main population groupings: a northern California, southern California, and Colorado Plateau group. The northern California populations represent a distinct group and include populations from the Santa Lucia Mountains contrary to current classifications. The southern California group consistently includes populations in the San Gabriel and Inyo Mountains and was unique from any other region. The Colorado Plateau represents a group distinct from all other groups. The resilience of C. humilis on the Colorado Plateau to human threats remains unknown, but based on its frequency being comparable to California and our findings that considerable genetic variation exists within the species and within populations on the Colorado Plateau, we recommend that the threatened status of C. humilis be lifted.