ELENA Commissioning

The Extra Low ENergy Antiproton storage ring (ELENA) is an upgrade project at the CERN AD (Antiproton Decelerator). ELENA will further decelerate the 5.3 MeV antiprotons coming from the AD down to 100 keV. ELENA features electron cooling for emittance control during deceleration thus preserving the beam intensity and allowing to extract bright bunches towards the experiments. The lower energy will allow for increasing the antiproton trapping efficiency up to two orders of magnitude, which is typically less than 1% with the present beam from AD. The ring was completed with the installation of the electron cooler at the beginning of 2018. Decelerated beams with characteristics close to the design values were obtained before the start of CERN Long Shutdown 2 (LS2). During LS2 electrostatic transfer lines from the ELENA ring to the experimental zones will be installed, replacing the magnetic transfer lines from the AD ring. The latest results of commissioning with H⁻ and antiprotons and the first observation of electron cooling in ELENA will be presented, together with an overview of the project and status and plans for LS2 and beyond.