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  1. Evans, Christopher J. ; Bryant, Julia J. ; Motohara, Kentaro (Ed.)
    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. 
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  2. Evans, Christopher J. ; Bryant, Julia J. ; Motohara, Kentaro (Ed.)
    NIRSPEC is a high-resolution near-infrared echelle spectrograph on the Keck II telescope that was commissioned in 1999 and upgraded in 2018. This recent upgrade was aimed at improving the sensitivity and longevity of the instrument through the replacement of the spectrometer science detector (SPEC) and slit-viewing camera (SCAM). Commissioning began in 2018 December, producing the first on-sky images used in the characterization of the upgraded system. Through the use of photometry and spectroscopy of standard stars and internal calibration lamps, we assess the performance of the upgraded SPEC and SCAM detectors. First, we evaluate the gain, readnoise, dark current, and the charge persistence of the spec detector. We then characterize the newly upgraded spectrometer and the resulting improvements in sensitivity, including spectroscopic zero points, pixel scale, and resolving power across the spectrometer detector field. Finally, for SCAM, we present zero points, pixel scale, and provide a map of the geometric distortion of the camera. 
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  3. Evans, Christopher J. ; Bryant, Julia J. ; Motohara, Kentaro (Ed.)
    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. 
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  4. Evans, Christopher J. ; Bryant, Julia J. ; Motohara, Kentaro (Ed.)
    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. 
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  5. Abstract

    Since the start of science operations in 1993, the twin 10‐m 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 through collaborative partnerships with Caltech, the University of California, and the University of Hawaii instrument development teams along with industry and other organizations. The observatory adapts and responds to the observers' evolving needs as defined in the observatory's strategic plan periodically refreshed in collaboration with the science community. This paper is an overview of the instrumentation projects that range from commissioning to early conceptual stages. An emphasis is placed on the detector, detector controllers, and capability needs that are driven by the desired future technology defined in the 2022 strategic plan.

     
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