GPI2.0 is an upgrade of the high-contrast instrument known as the Gemini Planet Imager (GPI). This new version is scheduled for installation on Gemini North telescope by the end of 2024. In this document, we outline our approach for addressing Non-Common Path Aberrations (NCPA) measurement and correction within the instrument. Our strategy differs significantly from the methods employed in the original GPI. Our proposal involves the utilization of a dedicated Wavefront Sensor (WFS) positioned within the coronagraph branch to accurately measure NCPAs. Subsequently, we will compensate for these aberrations by transmitting offset signals to the adaptive optics WFS. The chosen dedicated WFS will be a Zernike WFS (ZWFS), known for its exceptional sensitivity. This paper provides insights into the integration plan for incorporating the ZWFS into GPI2.0, details its key characteristics, and outlines the methodology for performing phase inversion based on the ZWFS measurements. Additionally, we present the initial results of experimental tests conducted on the SEAL testbed at the University of California, Santa Cruz (UCSC).
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