A determination of the K-correction for quasars

The K-correction is made up of an emission line component and a continuum component. These two components are iteratively determined in this paper from line widths and intensities, redshifts, U,B,V colours and radio spectral indices for 355 quasars. The colors B-V and U-B, corrected for the emission line portion of the K-correction, are plotted against Z, giving 2 mean relations. Eliminating Z between these gives a mean optical continuum, which is then used to calculate the continuum portion of the K-correction.