Stark broadening effect in hot DA white dwarfs: Ultraviolet lines of Fe V

Stark widths and shifts have been calculated for 17 ultraviolet lines of Fe V of astrophysical interest. The calculations have been made using semiclassical perturbation approach. The work is motivated by the importance of ultraviolet lines for the study of hot white dwarf atmospheres specially for investigations of the variation of fine structure constant in strong gravitational field. Our Stark broadening parameters are presented for a range of temperature from 50,000 to 600,000 K. Our results are used to investigate the importance of electron impact broadening in plasma conditions of hot DA white dwarfs. Electron impact Stark width is compared to Doppler width as a function of atmospheric layer temperature and as a function of logarithm of Rosseland optical depth.