AD/ELENA Electron Cooling Experience During and after CERNs Long Shutdown (LS2)

Electron cooling is a key ingredient of the Antimatter Factory at CERN, now composed of the AD and ELENA rings, both featuring an electron cooler. After the successful commissioning of the ELENA ring and electron cooling with antiprotons in 2018, the facility was shut down for the CERN long shutdown (LS2). In the meantime, ELENA has been operating with H⁻ ions generated from a local source, and electron cooling of H⁻ was demonstrated. The facility has restarted with antiproton operation during summer 2021, and it is now delivering 100 keV production beams through newly installed electro-static extraction lines to all the experiments for the very first time. We will give an overview of the experience gained and difficulties encountered during the restart of the AD and ELENA electron coolers. The experience with electron cooling of H⁻ beam in ELENA and the comparison with antiproton cooling will also be presented.