X-ray spectra from laser produced highly ionized hafnium plasma in the 4.6-5.0 angstrom range

X-ray band spectra from laser produced highly ionized hafnium plasmas have been observed in the 4.6-5.0 Angstrom range. The contributions from electro n-impact excitation and dielectronic recombination in this region are studi ed in detail using a quasi-relativistic configuration interaction method. I t is found that the spectral structure due to electron-impact excitations i s almost the same as in dielectronic recombination. The calculated spectra of 3d-5f transitions of the Ni-Ge ionization states can explain the observe d features of the band spectra in this region very well.