Technical description and performance of the phase II version of the Keck Planet Imager and Characterizer
Abstract
The Keck Planet Imager and Characterizer (KPIC) is a series of upgrades for the Keck II Adaptive Optics (AO) system and the NIRSPEC spectrograph to enable diffraction limited, high resolution (R>30000) spectroscopy of exoplanets and low mass companions in the K and L bands. Phase I consisted of single mode fiber injection/extraction units (FIU/FEU) used in conjunction with a H band pyramid wavefront sensor. The use of single mode fibers provides a gain in stellar rejection, a substantial reduction in sky background, and an extremely stable line spread function in the spectrograph. Phase II, deployed and commissioned in 2022, brought a 1000 actuator deformable mirror, beam shaping optics, a vortex mask, and other upgrades to the FIU/FEU. An additional service mission in 2024 extended operations down to y band, delivered an atmospheric dispersion corrector, and provided access to two laser frequency combs. KPIC phase II brings higher planet throughput, lower stellar leakage and many new observing modes which extend its ability to characterize exoplanets at high spectral resolution, building on the success of phase I. In this paper we present a description of the final phase II version of KPIC, along with results of system level laboratory testing and characterization showing the instrument's phase II throughput, stability, repeatability, and other key performance metrics prior to delivery and during installation at Keck. We outlined the capabilities of the various observing modes enabled by the new modules as well as efforts to compensate for static aberrations and non common path errors at Keck, which were issues that plagued phase I. Finally, we show results from commissioning.
Cite
@article{arxiv.2502.01863,
title = {Technical description and performance of the phase II version of the Keck Planet Imager and Characterizer},
author = {Nemanja Jovanovic and Daniel Echeverri and Jacques-Robert Delorme and Luke Finnerty and Tobias Schofield and Jason J. Wang and Yinzi Xin and Jerry Xuan and J. Kent Wallacee and Dimitri Mawet and Aniket Sanghi and Ashley Baker and Randall Bartos and Charlotte Z. Bond and Benjamin Calvin and Sylvain Cetre and Greg Doppmann and Michael P. Fitzgerald and Jason Fucik and Maodong Gao and Jinhao Ge and Charlotte Guthery and Katelyn Horstman and Chih-Chun Hsud and Joshua Liberman and Stephanie Leifer and Scott Lilley and Ronald Lopez and Eduardo Marin and Emily C. Martin and Bertrand Mennesson and Evan Morris and Reston Nash and Jacklyn Pezzato and Michael Porter and Mitsuko Roberts and Garreth Ruane and Jean-Baptiste Ruffio and Ben Sappey and Eugene Serabyn and Boqiang Shen and Andrew Skemer and Ji Wang and Edward Wetherell and Peter Wizinowich and Maissa Salama and Vincent Chambouleyron and Rebecca Jensen-Clem and Chas Beichman},
journal= {arXiv preprint arXiv:2502.01863},
year = {2025}
}
Comments
36 pages, 16 figures