Panel a: period distributions of synthetic CEMP-s stars computed with our model set M2 and with different adopted detection thresholds for radial-velocity variations. The dashed black line shows the period distribution of all the CEMP-s stars in our simulation. The dot-dashed blue and dotted orange lines show the period distributions of the simulated CEMP-s stars with detection thresholds of K_min = 0.1 and 0.5 km s⁻¹, respectively. Panel b: same as in panel a for synthetic CEMP-s stars that would be detected as singles with the above thresholds. Panel c: the cumulative orbital-period distributions corresponding to the models in panel a are compared with the observed distribution calculated with the data of Hansen et al. (2016, solid grey line).