Extra Low Energy Antiproton ring
Extra Low ENergy Antiproton ring (ELENA) is a 30 m hexagonal storage ring that decelerates antiproton beams and delivers it to different AD experiments. It is situated inside the Antiproton Decelerator (AD) complex at CERN, Geneva. It is designed to further decelerate the antiproton beam coming from the Antiproton decelerator to an energy of 0.1 MeV for more precise measurements. The first beam circulated ELENA on 18 November 2016. The ring is expected to be fully operational by the end of the Long Shutdown 2 (LS2) in 2021.
| ELENA | Extra low energy antiproton ring – further decelerates antiprotons coming from AD |
|---|---|
| AD experiments | |
| ATHENA | AD-1 Antihydrogen production and precision experiments |
| ATRAP | AD-2 Cold antihydrogen for precise laser spectroscopy |
| ASACUSA | AD-3 Atomic spectroscopy and collisions with antiprotons |
| ACE | AD-4 Antiproton cell experiment |
| ALPHA | AD-5 Antihydrogen laser physics apparatus |
| AEgIS | AD-6 Antihydrogen experiment gravity interferometry spectroscopy |
| GBAR | AD-7 Gravitational behaviour of anti-hydrogen at rest |
| BASE | AD-8 Baryon antibaryon symmetry experiment |
| PUMA | AD-9 Antiproton unstable matter annihilation |
GBAR experiment (AD-7) was the first experiment to use a beam from ELENA, with the rest of the AD experiments following suit after LS2 when beam transfer lines from ELENA will have been laid to all the experiments using the facility. Long Shutdown 2 (LS2) officially ended on July 5, 2022 with the beginning of LHC Run 3. Antiprotons from ELENA have been available to the MUSASHI trap of the ASACUSA CUSP experiment from August 2021.