  This article presents a numerical investigation of overtaking collisions
between two solitary waves in the context of the Schamel equation. Our study
reveals different regimes characterized by the behavior of the wave
interactions. In certain regimes, the collisions maintain two well-separated
crests consistently over time, while in other regimes, the number of local
maxima undergoes variations following the patterns of $2\rightarrow
1\rightarrow 2\rightarrow 1\rightarrow 2$ or $2\rightarrow 1\rightarrow 2$.
These findings demonstrate that the geometric Lax-categorization observed in
the Korteweg-de Vries equation (KdV) for two-soliton collisions remains
applicable to the Schamel equation. However, in contrast to the KdV, we
demonstrate that an algebraic Lax-categorization based on the ratio of the
initial solitary wave amplitudes is not feasible for the Schamel equation.
Additionally, we show that the statistical moments for two-solitary wave
collisions are qualitatively similar to the KdV equation and the phase shifts
after soliton interactions are close to ones in integrable KdV and modified KdV
models.

Plasma Physics;Pattern Formation and Solitons