Discrete structure in the 3dphotoabsorption spectra of neutral, singly ionized and doubly ionized bromine

The 3d photoabsorption spectra of Br, ${\mathrm{Br}}^{+}$, and ${\mathrm{Br}}^{2+}$ have been recorded photographically in the 60–90 eV region using the dual-laser-produced plasma technique. In each case intense 3d→4p transitions were observed while 3d→np (n≳4) features were also obtained in the spectrum of neutral bromine. The transitions were classified with the aid of multiconfiguration Hartree-Fock calculations. The excited states are predicted to decay by direct autoionization involving 4s or 4p electrons and the rates for the different processes and resulting linewidths were also calculated. From these data theoretical cross sections for the observed features were also computed. © 1996 The American Physical Society.