Based on the spectroscopic observations secured with the telescopes and spectrographs of the Dominion Astrophysical Observatory and Ondrejov Observatory.

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Table 2 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/459/849

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... II 6578.052 $\AA$

The measured RV of the other member of the C II doublet turned out to be influenced by a nearby weak emission line and a telluric line at certain orbital phases - see Fig. 3. The same figure shows that, although the spectral lines vary slightly in their strengths and widths, no clear phase dependence could be established.

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... one

Dataset 8 consists of only 2 RVs obtained at very similar orbital phases. This leads to a very small rms error for this dataset and the weighting scheme we use would strongly overestimate the weight of this dataset. We therefore kept the weight of dataset 8 equal to 1.

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...interchanged

It is known that during the process of mass exchange, the conservation of the orbital angular momentum causes a decrease in the orbital period until the masses of binary components get interchanged.

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