The Keck Planet Imager and Characterizer (KPIC) is an upgrade to the Keck II adaptive optics system that includes an active fiber injection unit (FIU) for efficiently routing light from exoplanets to NIRSPEC, a high-resolution spectrograph. The second phase of this upgrade, beginning at the end of 2019, will add a suite of new coronagraph modes as well as a 1000-actuator deformable mirror. One of these modes, operating in the K-band (2.2µm), will be the first Vortex Fiber Nuller (VFN) to go on sky. Vortex Fiber Nulling is a new interferometric method for suppressing starlight in order to spectroscopically characterize exoplanets at angular separations that are inaccessible with conventional coronagraph systems. A monochromatic starlight suppression of 6x10^{-5} has already been demonstrated with a VFN in the lab, thereby exceeding our goal performance, and a polychromatic demonstration is underway. Here we describe the new KPIC coronagraph modes and present the expected performance of the VFN mode using realistic parameters determined from on-sky tests done during the KPIC commissioning. We will also present the latest experimental results of the system using a laboratory replica of the KPIC instrument.
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