Speaker
Description
Osmium is the element of the Periodic Table with the atomic number Z equal to
76. In Tokamaks with divertors made of tungsten (Z = 74), it will be produced in the neutron-induced transmutation of the latter. Therefore one can expect that their sputtering may generate ionic impurities of all possible charge states in the fusion plasma. As a consequence, these could contribute to radiation losses in these controlled nuclear devices. The knowledge of radiative rates in all the spectra of osmium is thus important in this field. In this framework, a multiplatform approach has been used to determine the Os V radiative properties and estimate their accuracy. The transition probabilities and the oscillator strengths have been computed for the 2677 electric dipole (E1) transitions falling in the spectral range from 400 to 12000 Angstroms. Three independent atomic structure models have been considered; one based on the fully relativistic ab initio multiconfiguration Dirac-Hartree-Fock (MCDHF) method and two based on the semi-empirical pseudo-relativistic Hartree-Fock (HFR) method.
