Contour plots of the detection significance of the four selected chemical species. The solid (dashed) lines represent the 1 σ (2 σ) interval around the peak value of the significance (marked with a red cross). These intervals are computed as described in the text. The point of the K_p – V_rest map in which the 2 black dashed lines (the horizontal one corresponds to the expected K_p value, while the vertical one corresponds to V_rest = 0 km s⁻¹) cross each other represents the expected detection significance peak position in the case in which the detected signal has a planetary origin. As it can be the significance peak position is compatible with the planetary origin hypothesis at better than 1 σ for all the 4 species.