Acceleration of Nitrogen Ions to 7.4 Gev in the Princeton Particle Accelerator

Abstract
Nitrogen ions in charge states N5+ and N6+ have been accelerated in the Princeton Particle Accelerator to 4 and 7.4 billion electron volts (Gev), respectively. An external N5+ beam of 1 x 106 particles per second has been obtained and focused to a 6-millimeter-diameter spot. The N6+ beam was about 2 x 105 particles per second. The total charge-changing collision cross section of N5+ in water vapor was determined as a function of ion energy. The improvement in vacuum necessary to increase the N5+ beam at least tenfold was calculated. The N6+ total cross section is probably smaller than that of N5+ at the higher energies.