Figure 4: Observations of Efimov physics on Feshbach resonances in $39K$ and $7Li$. The decay of the trapped atomic samples is analyzed according to Eq. (2) and expressed in terms of the loss rate coefficient $L3$ as a function of the $s$-wave scattering length $a$. The results in (a) were obtained in Florence on a broad Feshbach resonance in $39K$ atoms [30]. The data in (b) and (c) show the results on $7Li$ from Bar Ilan University [31] and Rice University [32], respectively. These two experiments employed Feshbach resonances in two different atomic states.