Cumulative histograms of minimum mass (left) and semi-major axis (right) of synthetic and observable planets around M stars. In each case, we only take into account planets whose induced Doppler semi-amplitude is larger than 10 m/s, and periods shorter than 3 years. Moreover, we exclude planets located at distances closer than 0.1 AU (the internal limit of our computational disk). For synthetic planets (heavy lines), we used the formation model around 0.5 M_⊙ stars, whereas we selected planets discovered around stars with masses between 0.3M_⊙ and 0.8M_⊙ (step-like lines). The three heavy lines represent the formation model around a 0.5M_⊙ star for α_D equal to 1.2 (solid line), 0 (dotted line), and 2 (dashed line). The thin solid line is for a primary mass of 1.0 M_⊙. The results of a statistical comparison between the different curves is indicated in Table 3.