Excitation of atoms and molecules in collisions with highly charged ions

Much of the work this year has been directed toward studies of charge exchange and ionization in single collisions of heavy ions with gaseous atoms and molecules. A study of the double ionization of He by high energy N7+ ions, which began last year, was extended up in energy to 40 MeV/amu. These measurements verified the deviations from the predictions of theory observed in our previous work and indicated that the energy required to reach the limiting value of the ratio of double-to-single ionization cross sections may be as high as 70 MeV/amu