Skipper mosaic on the SOAR Integral Field Spectrograph

Current Skipper CCD technology has been in use in particle physics experiments since its successful testing in 2017 at Fermilab and LBNL[3] while achieving readout noise values as low as 0.039 e-[4]. This extremely low noise presents a very interesting potential for certain astronomical applications where the background photon noise does not dominate, and the ability of Skipper CCDs to be tuned for a desired readout noise allows for a wide range of applications. In this current paper we present the engineering work performed in cryo-mechanics and electronics (Dewar, detector mount, preamplifier, etc.) at NOIRLab-CTIO to test a 4-Skipper CCD mosaic on sky with the SOAR Integral Field Spectrograph (SIFS). This work was performed in the context of a NOIRLab/FermiLab/U.Chicago/LBNL collaboration for testing of the Skipper devices on the sky. We also present the mosaic characterization results of the detectors from the laboratory, as well as the final engineering performance results from on sky observations.