First row: periodogram of the total RV signal added to the RV signal due to a 1 M_Earth at 1.2 AU after correction (method described in Sect. 4.2), with the Set 1 sampling (all days) and no Ca noise. The vertical dotted line indicates the position of the planet peak. The left panel shows the best detection case out of 7 planet phases, while the right panel shows the worse case. Second row: same for Set 2 and no Ca noise. Third row: same for Set 1, high Ca S/N, and a Ca realisation leading to a detection limit below 1 M_Earth. Fourth row:same for Set 1, high Ca S/N, and a Ca realisation leading to a detection limit above 1 M_Earth for the correlation method (1.6 M_Earth). Power is in arbitrary unit but on the same scale on all plots.