Electron-impact excitations of the autoionizing states of bismuth

Electron-impact excitation from the ground state of bismuth has been studied with electron energy-loss spectra. We have identified 14 autoionized states in the region up to 13.5 eV. Three states at 7.34, 9.97 and 11.2 eV have been recorded for the first time, they have not been observed previously either in photoabsorption spectroscopy or in arc spectra. The present energy level values are compared with the limited number of available data.