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where f<sub>0</sub> is the center frequency, t<sub>0</sub> is the time delay, t is the Gaussian pulse width, and F Φ is a constant phase. In the limits, the above waveform can be reduced either to a simple Gaussian pulse:
:<math> E_j^{inc}(r,t) = E_0(r) \exp \left(-\frac{(t-t_0)^2}{\tau ^2} \right),\quad j=x,y,z </math>