STUDY OF RELATIVE LEVEL POPULATIONS IN BEAM-FOIL EXCITED LI, BE, AND MG

We have studied the optical beam-foil spectra of Li, Be, and Mg in the wavelength region 200-550 nm by use of a quantum efficiency calibrated monochromator at projectile energies of 210 keV for Li, 156, 256, and 356 keV for Be, and 100 keV for Mg. The relative population for different Rydberg levels of the same term series decreases in most cases somewhat faster than (n*)-3, as is also observed in ion-atom encounters under single collision conditions. The relative level population for levels of the same principal quantum number increases generally with the orbital angular momentum quantum number, and superimposed on this increase is a peaking for p levels. The relative population of levels of the same charge state and with the same core configuration is unaffected by change of the projectile energy. © 1979 Springer-Verlag.