Propagation of chirped pulses inside self-action temporal guide

Based on two order approximation of the variation of refraction index produced by self-action while optical pulses are traveling in Kerr-medium,the propagation equation has been solved.Furthermore,the strict analytical expressions of the amplitude,width and chirp parameter of chirped Gaussian pulse,relative to the propagation distance,are deduced.The solitary wave traveling conditions of fundamental mode Gaussian pulse have been discussed.