A quantitative measure of carrier shocking

I propose a definition for a "shocking coefficient" $S$ intended to make determinations of the degree of waveform shocking, and comparisons thereof, more quantitative. This means we can avoid having to make ad hoc judgements on the basis of the visual comparison of wave profiles.Comment: 5 pages, 6 figure

Limits of the uni-directional pulse propagation approximation

I apply the method of characteristics to both bi-directional and uni-directional pulse propagation in dispersionless media containing nonlinearity of arbitrary order. The differing analytic predictions for the shocking distance quantify the effects of the uni-directional approximation used in many pulse propagation models. Results from numerical simulations support the theoretical predictions, and reveal the nature of the coupling between forward and backward waves.Comment: 6 pages, 6 figures; this version contains an additional appendix not present in the published versio