Caption of ElectronsMotionsAndPulseMovieR16M26.avi = Video1-mmc3:

Trajectories  (gone in about 150 fs) of electrons initially located at  
the longitudinal positions 
\  $Z/Z_{{\scriptscriptstyle M}}=0,  0.25 , 0.5 ,  0.75 ,1$, from bottom up.  
The conditions are the same as   in fig. 5.


Caption of DensityMovieR16M26.avi = Video2-mmc2:

Evolution of the  pulse amplitude (purple), normalized ion density (red) and normalized
electron density
(blue), under the same conditions as in fig. 5.



Caption of  ChargeDensityPlotMovieR16M26.avi = Video3-mmc1:

Normalized charge density plot $1\!-\!n/n_0$ under the same conditions as in fig. 5;
after a while the electrons travelling backwards
make  light yellow-striped the region between the yellow  and the blue striped ones.