coupling to dynamic field $D$. This regime is almost deterministic, with pedestrians moving straight towards the exit on the shortest path. Now an increased $\mu$ value introduces a negative interaction between the particles into the system, i.e. the pedestrians hinder each other due to strong competition for the unoccupied target sites near the exit. So a strong coupling to $S$ together with a high $\mu$ value, which works as an internal local pressure between the particles, describes a typical panic situation, where an ordered outflow is inhibited due to local conflicts near bottlenecks or doors, resulting in strongly increased evacuation times (such situations are well known from emergency evacuations due to fire or other reasons in sports arenas or passenger vessels).

![Evacuation time as function of the sensitivity parameter $k_S$ for different $\mu$ values ($k_D=0$, $\rho=0.3$).[]{data-label="plot_4"}](\DIR/fig9.eps){width="0.9\columnwidth"}

This can be seen in fig. \[plot\_4\], where the influence of an increased coupling strength to $S$ for fixed $\mu$ is shown. For $k_S\longrightarrow 0$ the particles perform a pure random walk and the evacuation times are very large and almost independent of $\mu$. In this situation conflicts between the particles are not very important for the dynamics. In contrast, for $k_S\longrightarrow\infty$ they choose 