Antiproton Beam Extraction for the ALPHA Antihydrogen Experiment

The ALPHA experiment produces antihydrogen atoms by slowly merging cold plasmas of positrons and antiprotons inside a nested Penning-Malmberg trap. During each experimental cycle, antiprotons are delivered from the the CERN Antiproton Decelerator (AD) in a dedicated Penning trap known as the Catching Trap (CT) before being transferred to other parts of the apparatus. There is around 20% loss of antiprotons during particle transfers in each experimental cycle, this antiproton loss reduces the antihydrogen atoms produced during each cycle. In order to fix this, simulations were ran in a simplified section of the current ALPHA antiproton catching trap in order to produce short pulsed beams with narrow energy distributions. A relation of between the longi- tudinal emittance of the antiproton beam and the initial Penning trap voltages was studied, along with proper time constants, initial voltages and particle numbers for running future simulations.