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As part of the Keck Planet Finder (KPF) project, a Fiber Injection Unit (FIU) was implemented and will be deployed on the Keck Ⅰ telescope, with the aim of providing dispersion compensated and tip/tilt corrected light to the KPF instrument and accompanying H&K spectrometer. The goal of KPF is to characterize exoplanets via the radial velocity technique, with a single measurement precision of 30cm/s or better. To accomplish this, the FIU must provide a stable F-number and chief ray angle to the Science and Calcium H&K fibers. Our design approach was use a planar optical layout with atmospheric dispersion compensation for both the Science and Calcium H&K arms. A SWIR guider camera and piezo tip/tilt mirror are used to keep the target centered on the fibers. 

As part of the Keck All-sky Precision Adaptive optics (KAPA) project a laser Asterism Generator (AG) is being implemented on the Keck I telescope. The AG provides four Laser Guide Stars (LGS) to the Keck Adaptive Optics (AO) system by splitting a single 22W laser beam into four beams of equal intensity. We present the design and implementation of the AG for KAPA. We discuss the optical design and layout, the details of the mechanical design and fabrication, and the challenges of designing the assembly to fit into the limited available space on the Keck telescope. 

We calculate an optical distortion solution for the OSIRIS Imager on the Keck I telescope, by matching observations of globular clusters to a Hubble reference catalogue. This solution can be applied to correct astrometric distortions in OSIRIS frames, improving the astrometric accuracy of observations. We model the distortion with a 5th order Legendre polynomial. The distortion we find matches the expected OSIRIS distortion, and has a fit error of 0.6 mas, but has large residuals of 7 mas. We are currently iterating on an improved reference frame to improve the residual. Additionally, we have installed the Precision Calibration Unit (PCU) on the Keck I optical bench, which will generates an artificial grid of stars for use in future distortion calculations. 

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. 

The W. M. Keck Observatory Adaptive Optics (AO) facilities have been operating with a Field Programmable Gate Array (FPGA) based real time controller (RTC) since 2007. The RTC inputs data from various AO wavefront and tip/tilt sensors; and corrects image blurring from atmospheric turbulence via deformable and tip/tilt mirrors. Since its commissioning, the Keck I and Keck II RTCs have been upgraded to support new hardware such as pyramid wavefront and infrared tip-tilt sensors. However, they are reaching the limits of their capabilities in terms of processing bandwidth and the ability to interface with new hardware. Together with the Keck All-sky Precision Adaptive optics (KAPA) project, a higher performance and a more reliable RTC is needed to support next generation capabilities such as laser tomography and sensor fusion. This paper provides an overview of the new RTC system, developed with our contractor/collaborators (Microgate, Swinburne University of Technology and Australian National University), and the initial on-sky performance. The upgrade includes an Interface Module to interface with the wavefront sensors and controlled hardware, and a Graphical Processing Unit (GPU) based computational engine to meet the system’s control requirements and to provide a flexible software architecture to allow future algorithms development and capabilities. The system saw first light in 2021 and is being commissioned in 2022 to support single conjugate laser guide star (LGS) AO, along with a more sensitive EMCCD camera. Initial results are provided to demonstrate single NGS & LGS performance, system reliability, and the planned upgrade for four LGS to support laser tomography. 

We present the status and plans for the Keck All sky Precision Adaptive optics (KAPA) program. KAPA includes (1) an upgrade to the Keck I laser guide star adaptive optics (AO) facility to improve image quality and sky coverage, (2) the inclusion of AO telemetry-based point spread function estimates with all science exposures, (3) four key science programs, and (4) an educational component focused on broadening the participation of women and underrepresented groups in instrumentation. For this conference we focus on the KAPA upgrades since the 2020 SPIE proceedings1 including implementation of a laser asterism generator, wavefront sensor, real-time controller, asterism and turbulence simulators, the laser tomography system itself along with new operations software and science tools, and modifications to an existing near-infrared tip-tilt sensor to support multiple natural guide star and focus measurements. We will also report on the results of daytime and on-sky calibrations and testing. 

We present the status and plans for the Keck All sky Precision Adaptive optics (KAPA) program. KAPA includes four key science programs, an upgrade to the Keck I laser guide star (LGS) adaptive optics (AO) facility to improve image quality and sky coverage, AO telemetry based point spread function (PSF) estimates for all science exposures, and an educational component focused on broadening the participation of women and underrepresented groups in instrumentation. For the purpose of this conference we will focus on the AO facility upgrade which includes implementation of a new laser, wavefront sensor and real-time controller to support laser tomography, the laser tomography system itself, and modifications to an existing near-infrared tip-tilt sensor to support multiple natural guide star (NGS) and focus measurements. 

Since the start of science operations in 1993, the twin 10-meter W. M. Keck Observatory (WMKO) telescopes have continued to maximize their scientific impact and to produce transformative discoveries that keep the observing community on the frontiers of astronomical research. Upgraded capabilities and new instrumentation are provided though collaborative partnerships with Caltech, the University of California, and the University of Hawaii instrument development teams, as well as industry and other organizations. This paper summarizes the performance of recently commissioned infrastructure projects, technology upgrades, and new additions to the suite of observatory instrumentation. We also provide a status of projects currently in design or development phases and, since we keep our eye on the future, summarize projects in exploratory phases that originate from our 2022 strategic plan developed in collaboration with our science community to adapt and respond to evolving science needs. 

The Keck Planet Finder (KPF) is a fiber-fed, high-resolution, high-stability spectrometer in development at the UC Berkeley Space Sciences Laboratory for the W.M. Keck Observatory. KPF is designed to characterize exoplanets via Doppler spectroscopy with a goal of a single measurement precision of 0.3 m s-1 or better, however its resolution and stability will enable a wide variety of astrophysical pursuits. Here we provide post-preliminary design review design updates for several subsystems, including: the main spectrometer, the fabrication of the Zerodur optical bench; the data reduction pipeline; fiber agitator; fiber cable design; fiber scrambler; VPH testing results and the exposure meter. 

Using the Keck Planet Imager and Characterizer, we obtained high-resolution (R∼ 35,000)K-band spectra of the four planets orbiting HR 8799. We clearly detected H₂O and CO in the atmospheres of HR 8799 c, d, and e, and tentatively detected a combination of CO and H₂O in b. These are the most challenging directly imaged exoplanets that have been observed at high spectral resolution to date when considering both their angular separations and flux ratios. We developed a forward-modeling framework that allows us to jointly fit the spectra of the planets and the diffracted starlight simultaneously in a likelihood-based approach and obtained posterior probabilities on their effective temperatures, surface gravities, radial velocities, and spins. We measured$v\sin (i)$values of${10.1}_{-2.7}^{+2.8}\mathrm{km}{\mathrm{s}}^{-1}$for HR 8799 d and${15.0}_{-2.6}^{+2.3}\mathrm{km}{\mathrm{s}}^{-1}$for HR 8799 e, and placed an upper limit of <14 km s⁻¹of HR 8799 c. Under two different assumptions of their obliquities, we found tentative evidence that rotation velocity is anticorrelated with companion mass, which could indicate that magnetic braking with a circumplanetary disk at early times is less efficient at spinning down lower-mass planets.