Design and test of a beam line for extraction of slow antiprotons from a multi-ring electrode ion trap

A new monoenergetic slow antiproton beam facility has recently been installed at the CERN Antiproton Decelerator (AD). The system is designed to deliver pulsed or continuous antiproton beams in the 10-1000 eV energy region which is suitable for various interesting atomic and molecular spectroscopic and collision studies. The antiprotons obtained from the AD are slowed down to around 100 keV by passing the Radio Frequency Quadrupole Decelerator (RFQD) and then captured in a multi-ring electrode ion trap. After electron cooling down to a few eV, the antiprotons will be extracted out from the trap into a collision chamber via a differential pumping system. In this paper, we present recent results in which the antiproton capture and cooling phases of this scheme have been successfully demonstrated. Furthermore, the design and tests of the extraction and differential pumping system are presented. (8 refs)