IUE data analysis : radial velocities from line coincidence statistics.

Abstract

The authors have employed the method of wavelength coincidence statistics (WCS) to determine radial velocities from International Ultraviolet Explorer (IUE) satellite data for several chemically peculiar stars. By repeatedly carrying out the entire WCS procedure with a sequence of radial velocities, the authors demonstrate that significance-weighted mean velocities can be obtained which are accurate to within the uncertainties imposed by the stellar wavelengths, viz. ≤5 km s^-1 for sharp-lined stars. The use of this approach to derive velocity information from IUE spectra containing wavelength scale errors and to identify stars with composite spectra is discussed.