This award supports cooperative research in the physics of atomic collisions between Walter Meyerhof of Stanford University and E.C. Montenegro of the Catholic University in Rio de Janeiro, Brazil. They will study the charge capture and loss by electron transfer during the ionic bombardment of gaseous atomic targets. The total and differential charge changing cross-sections will be measured at both laboratories to investigate the transition region from low to intermediate velocities. Stanford has a Tandem accelerator which can provide projectile energies from 6 to 40 MeV while the Van de Graaff accelerator at the Catholic University yields 1 to 4 MeV. Both facilities are currently being improved but they cover a wider energy range than either alone. Therefore the two groups, both through the facilities and their experience, complement each other. The Brazilians have expertise in atomic theory helpful to Stanford with its expertise in the higher energy, heavy-ion regime. This effort will continue a recent collaboration which has produced three papers in 16 months.
