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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)We present the first science results and new technical milestones from the Robo-AO-2 facility at the University of Hawaii 2.2-m telescope. Following successful commissioning, the system began science operations in 2025. We are starting a large-scale survey of young stars in the Scorpius-Centaurus association to detect sub-stellar companions, vetting the Habitable Worlds Observatory Target Stars and Systems list, and discovering stellar blends for TESS exoplanet host candidates. We report on the commissioning of the natural guide star wavefront sensor, supporting science and future hybrid laser-stellar sensing demonstrations. Finally, we detail the automation of the telescope facility, Robo88, via updated telescope control systems and absolute encoders, and the integration of Robo-AO-2 with the telescope’s new adaptive secondary mirror.more » « lessFree, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)IRTF-ASM-1 has been functioning well since its first light in 2024. This adaptive secondary mirror (ASM) was primarily developed to be an on-sky demonstration of the new hybrid variable reluctance actuator technology at the NASA Infrared Telescope Facility (IRTF). However, due to its physical robustness and our previous demonstrations of sensitivity enhancements with the ASM, we are interested in using it to optimize telescope image quality on a nightly basis. This will directly benefit science observations. However, as IRTF does not currently have adaptive optics expertise, we have been developing the system to be used with minimal human intervention. We present our progress in developing software for active optics mode with IRTF-ASM-1 using the single conjugate, facility 2 × 2 Shack-Hartmann wavefront sensor Felix. We also present techniques for removing low-order, large amplitude non-common path aberrations between Felix and our science instruments.more » « lessFree, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Free, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Subaru/SCExAO/CHARIS enables near-infrared integral field spectropolarimetry. Quantitative polarimetry is useful for a variety of science cases, particularly measurements related to dust grain properties in circumstellar disks. This capability requires correcting for polarization effects from the optical path via a Mueller matrix model. We present an updated model accounting for the recently installed SCExAO near-infrared wavefront sensor YJH50 dichroic beamsplitter and the major Subaru Nasmyth beam-switcher upgrade. Using internal light source measurements from before and after the beam switcher installation, we find an elliptical retarder model for the image derotator improves polarimetric accuracy over the previous linear retarder model. We additionally find the YJH50 dichroic produces faint polarization effects that we cannot characterize with our Mueller matrix modeling capabilities, and that the Nasmyth beam-switcher has minimal polarization effects other than inducing a sign flip in Q and V polarized light. Using unpolarized standard star calibration measurements, we fit the diattenuation of Subaru's tertiary mirror as a function of wavelength and find that the diattenuation has increased since the previous CHARIS calibration. We calculate that the polarimetric accuracy of the model in the degree of linear polarization ranges from 0.02% to 0.12% for a 1% polarized target. This model update will soon be incorporated into CHARIS's data processing pipeline, and should be used for any polarimetric data taken after the Nasmyth beam-switcher update in October 2025. Additionally, we provide the code for this calibration as part of an open-source Python package for polarimetric calibration called pyPolCal, enabling straightforward re-calibration of the system after any future changes, e.g. the recent recoating of M3.more » « lessFree, publicly-accessible full text available August 19, 2027
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Schmidt, Dirk; Vernet, Elise; Jackson, Kathryn J (Ed.)Advanced astronomical instrumentation requires accessible, reconfigurable platforms to validate novel technologies and algorithms before on-sky deployment. We present the design, architecture, and alignment validation of the Hawaii Experimental Engineering Lab (He'e-Lab), a state-of-the-art modular testbed dedicated to two complementary research tracks: (A) the integration and characterization of astrophotonics components within a real-time computing loop, and (B) the development of advanced wavefront sensing and control (WFS&C) algorithms. The testbed features a broadband supercontinuum source (500 nm to 2 microns), a high-order 1k-actuator Boston Micromachines deformable mirror, and a 37-segment hexagonal mirror assembly providing piston-tip-tilt control to emulate segmented apertures like Keck and JWST. Downstream capabilities include a HASO 126 Shack-Hartmann sensor, a real-time computing environment driven by the CACAO package, and a modular injection platform coupled to a visible-wavelength spectrograph (R3, 000). We report on the successful system alignment and outline the roadmap for upcoming adaptive optics and photonic device validation frameworks.more » « lessFree, publicly-accessible full text available August 19, 2027
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