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We present progress on a conceptual design for a new Keck multi-conjugate adaptive optics system capable of visible light correction with a near-diffraction-limited spatial resolution. The KOLA (Keck Optical LGS AO) system will utilize a planned adaptive secondary mirror (ASM), 2 additional high-altitude deformable mirrors (DMs), and ≳ 8 laser guide stars (LGS) to sense and correct atmospheric turbulence. The field of regard for selecting guide stars will be 2’ and the corrected science field of view will be 60”. We describe science cases, system requirements, and performance simulations for the system performed with error budget spreadsheet tools and MAOS physical optics simulations. We will also present results from trade studies for the actuator count on the ASM. KOLA will feed a new optical imager and IFU spectrograph in addition to the planned Liger optical + infrared (λ > 850 nm) imager and IFU spectrograph. Performance simulations show KOLA will deliver a Strehl of 12% at g’, 21% at r’, 53% at Y, and 87% at K bands on axis with nearly uniform image quality over a 40”×40” field of view in the optical and over 60”×60” beyond 1 μm. Ultimately, the system will deliver spatial resolutions superior to HST and JWST (∼17 mas at r’-band) and comparable to the planned first-generation infrared AO systems for the ELTs. 

As part of the High order Advanced Keck Adaptive optics (HAKA) project, a state-of-the-art ALPAO 2844 actuator deformable mirror (DM) will replace the more than 25 years old 349 actuator DM on the Keck Adaptive Optics (AO) bench. The increase in the number of DM actuators requires a new set of pupil-relay optics (PRO) to map the 2.5mm DM actuator spacing to the 200μm lenslet spacing on the Shack-Hartmann wavefront sensor (WFS). A new lenslet array with increased focal lengths will be procured in order to maintain current plate scales. HAKA will initially support science with the near-infrared camera (NIRC2), a single mode fiber fed spectrograph (KPIC + NIRSPEC) and a fast visible imager (ORKID). In addition, a new infrared wavefront sensor (`IWA) is being designed to support science with ORKID and a suite of new science instruments: a mid-infrared coronagraphic integral field spectrograph (SCALES) and a fiber-fed high-resolution spectrograph (HISPEC). We present the opto-mechanical design of the HAKA DM, Shack-Hartmann WFS upgrades and the `IWA system. A mount for the HAKA DM will allow for quick integration and alignment to the Keck AO bench. The upgrade to the WFS PRO includes a new set of optics and associated mounting that fits within the mechanical constraints of the existing WFS and meets the requirements of the HAKA DM. 

The Keck All-Sky Precision Adaptive Optics (KAPA) system project will upgrade the Keck I AO system to enable laser tomography with a four laser guide star (LGS) asterism. This paper describes the new infrastructure which is being built for daytime calibration and testing of the KAPA tomographic algorithms. 

Abstract Wolf 359 (CN Leo, GJ 406, Gaia DR3 3864972938605115520) is a low-mass star in the fifth-closest neighboring system (2.41 pc). Because of its relative youth and proximity, Wolf 359 offers a unique opportunity to study substellar companions around M stars using infrared high-contrast imaging and radial velocity monitoring. We present the results ofMs-band (4.67μm) vector vortex coronagraphic imaging using Keck-NIRC2 and add 12 Keck-HIRES and 68 MAROON-X velocities to the radial velocity baseline. Our analysis incorporates these data alongside literature radial velocities from CARMENES, the High Accuracy Radial velocity Planet Searcher, and Keck-HIRES to rule out the existence of a close (a< 10 au) stellar or brown dwarf companion and the majority of large gas giant companions. Our survey does not refute or confirm the long-period radial velocity candidate, Wolf 359 b (P∼ 2900 days), but rules out the candidate's existence as a large gas giant (>4M_Jup) assuming an age of younger than 1 Gyr. We discuss the performance of our high-contrast imaging survey to aid future observers using Keck-NIRC2 in conjunction with the vortex coronagraph in theMsband and conclude by exploring the direct imaging capabilities with JWST to observe Jupiter- and Neptune-mass planets around Wolf 359. 

Uncorrected residual wavefront errors limit the ultimate performance of adaptive optics (AO) systems. We present different contributing factors and techniques to estimate and compensate these wavefront errors in the Keck natural guide star (NGS) AO systems. The error terms include low order static and semi-static aberrations from multiple sources, periodic and random segment piston errors, single-segment low order aberrations, wavefront sensor aliasing, vibrations, calibration drifts, and AO-to-telescope offload related errors. We present the design of a new AO subsystem, a residual wavefront controller (rWFC) to monitor the performance of the AO control loops and the image quality of the AO science instruments and apply the necessary changes to the telescope and AO parameters to minimize the residual wavefront errors. The distributed system consists of components at the telescope, AO bench and the science instruments. A few components of this system are already tested as on-demand standalone tools and will be integrated into a high-level graphical user interface (GUI) to operate the system. The software tool will periodically collect AO telemetry data, perform control loop parameter optimization and update AO parameters such as loop gains, centroid gain, etc. In addition, the system will analyze the science data at the end of each exposure and estimate telescope/AO performance when a bright point source is available in the science field. The benefits of reducing or eliminating the residual wavefront errors have broad implications for optical astronomy. Testing these techniques on a segmented telescope will be extremely useful to the teams developing high contrast AO systems for all extremely large telescopes and future segmented space telescopes. 

We report on progress at the University of Hawaii on the integration and testing setups for the adaptive secondary mirror (ASM) for the University of Hawaii 2.2-meter telescope on Maunakea, Hawaii. We report on the development of the handling fixtures and alignment tools we will use along with progress on the optical metrology tools we will use for the lab and on-sky testing of the system. 

Abstract Multiwavelength high-resolution imaging of protoplanetary disks has revealed the presence of multiple, varied substructures in their dust and gas components, which might be signposts of young, forming planetary systems. AB Aurigae bears an emblematic (pre)transitional disk showing spiral structures observed in the inner cavity of the disk in both the submillimeter (Atacama Large Millimeter/submillimeter Array (ALMA); 1.3 mm, 12 CO) and near-infrared (Spectro-polarimetric High-contrast Exoplanet Research; 1.5–2.5 μ m) wavelengths, which have been claimed to arise from dynamical interactions with a massive companion. In this work, we present new deep K s (2.16 μ m) and L ′ (3.7 μ m) band images of AB Aurigae obtained with the L/M-band Infrared Camera on the Large Binocular Telescope, aimed for the detection of both planetary companions and extended disk structures. No point source is recovered, in particular at the outer regions of the disk, where a putative candidate ( ρ = 0.″681, PA = 7.°6) had been previously claimed. The nature of a second innermost planet candidate ( ρ = 0.″16, PA = 203.°9) cannot be investigated by the new data. We are able to derive 5 σ detection limits in both magnitude and mass for the system, going from 14 M Jup at 0.″3 (49 au) down to 3–4 M Jup at 0.″6 (98 au) and beyond, based on the ATMO 2020 evolutionary models. We detect the inner spiral structures (<0.″5) resolved in both CO and polarimetric H -band observations. We also recover the ring structure of the system at larger separation (0.″5–0.″7) showing a clear southeast/northwest asymmetry. This structure, observed for the first time at L ′ band, remains interior to the dust cavity seen at ALMA, suggesting an efficient dust trapping mechanism at play in the disk.