deletions | additions       diff --git a/Figure_ref_fig_force_on_proton_shows__.tex b/Figure_ref_fig_force_on_proton_shows__.tex  index a49156c..1fab243 100644  --- a/Figure_ref_fig_force_on_proton_shows__.tex  +++ b/Figure_ref_fig_force_on_proton_shows__.tex 
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Figure \ref{fig:force_on_proton} shows the force on proton with $v = 1.8 ~\mathrm{a.u.}$ vs. the distance traveled. Note that the force in the direction of the velocity (solid green) does not average to zero, the average (negative) value agrees with the stopping power calculated from the energy increase (Fig. {fig:energy_distance}). \ref{fig:energy_distance}).  Note that there is transient effect at first ($\lesssim 5~a_0$), then the projectile reenters in the periodic supercell ($\gtrsim 20.46~a_0$). The consistency between energy slope and drag force is discussed in Ref. \cite{Schleife_2015}