Distributions of all observations, emission and the occurrence probability of the emission detected by the Nançay Decameter Array from 1990 to 2020. (a) and (b): Number of Jovian observations by the Nançay Decameter Array (NDA) plotted as a function of the Jovian longitude of the observer (CML) and the Io phase (PhIo) (in (a)) or Europa phase (PhEu) (in (b)), in 1° × 1° bins. (c) and (d): Number of emission detected by the NDA in 1° × 1° bins (CML×Φ_Io) (in (c)) and (CML×Φ_Eu) (in (d)). (e) and (f): occurrence probability of all the emission in 1° × 1°. (g) and (h): integration of the emission occurrence probability over the CML range of 210° × 320° as a function of the Europa phase, in 1° bins (in (g)) and in 5° bins (in (h)). This CML range corresponds to the one in plot (f) with most enhanced probability.