GSI-FAIR Colloquium

# Extra Low ENergy Antiproton ring ELENA

## by Christian Carli (CERN)

Tuesday, February 6, 2018 from to (Europe/Berlin)
at GSI Main Lecture Hall ( SB1 1.120 )
 Description The CERN Antiproton Decelerator AD provides antiproton beams with the lowest kinetic energy of 5.3 MeV possible with the given circumference of the machine to an active users community. Most experiments further decelerate the beam, typically by inserting a foil, to a few keV and capture the antiprotons in traps. With the given beam energy of 5.3 MeV, less than 1% of the delivered antiprotons can be captured. The Extra Low Energy Antiproton ring (ELENA) is a small synchrotron with a circumference of 30.4 m, a factor 6 smaller than the AD, to further decelerate antiprotons from the AD from 5.3 MeV to 100 keV. Controlled deceleration in a synchrotron equipped with an electron cooler to reduce emittances in all three planes will allow the existing AD experiments to increase substantially their antiproton capture efficiencies and render new experiments possible. Commissioning of the ELENA ring without the electron cooler has started with 100 keV H- beams from an ion source and antiprotons from the AD. The electron cooler has been installed at the end of last year and will be commissioned from February on. A status report on the ELENA project and, in particular, on ELENA ring commissioning taking place at present will be given. Material: