  The radial velocity curves of optical components in X-ray binary systems can
differ from the radial velocity curves of their barycenters due to tidal
distortion, gravitational darkening, X-ray heating, etc. This motivated us to
investigate how the semiamplitudes of the radial velocity curves of these
optical components can depend on the binary-system parameters in a Roche model.
The K-correction is taken to be the ratio of the radial velocity semiamplitude
for a star in the Roche model to the corresponding value for the stellar
barycenter. K-corrections are tabulated for the optical stars in the massive
X-ray binaries Cen X-3, LMC X-4, SMC X-1, Vela X-1, and 4U 1538-52.
