Acceleration and stacking of α particles in the CERN Linac, PS and ISR

The CERN Intersecting Storage Rings (ISR) have been successfully operated with sufficient α particles for experiments at total center of mass energies up to 120 GeV. Initially, the small beam currents obtainable from the (old) Linac hampered machine studies with the PS so that conclusive experiments similar to those done with deuterons were not possible. Recent attempts to increase the intensity by stripping a He+ beam at 520 keV succeeded and gave 10 mA of α particles from the Linac. Multiturn injection and acceleration in the PS produced 2×1011particles/pulse and stacking in the ISR resulted in a maximum stored beam intensity of 4.2 A at 52 GeV. After further acceleration by phase displacement in the ISR, luminosities of 4×1028cm-2s-1for α-α and 9×1029cm-2s-1for α-p experiments were obtained.