Identification labels: Interval: 520.2-520.3 nm---->label: 256 26.00 34328 397 256: last 3 digits of wavelengths in nm lambda=520.2256 nm 26.00 = Fe I 26=atomic number of the element (Fe), 00=charge (I) 34328=lower enrgy level in cm-1 397=per mil residual intensity of isolated line before broadening (rotational + instrumental)
In the plotted spectra RED labels are for the B star, BLACK labels are for the A starplot of the HARPS spectrum at phase 0.8167 The RV difference between the two stars is 147 km/sec. The spectrum of the B component is shifted on the left of that of the A component.