Time-Evolution of X-Ray Emission Nonuniformity in Line-Shaped Laser Plasmas

The spatially and time resolved 2D images of x-ray emission of line-shaped Ti laser plasmas have been obtained with a pinhole transmission grating spectrometer coupled with a x-ray streak camera. The x-ray emission nonuniformity of the plasma is quantitatively analyzed using a perturbation spectrum analysis method. The results show that the nonuniformity has a minimum value at a time corresponding to the peak time of the pumping laser pulse, and increases after that. A brief discussion on the nonuniformity mechanism has also been presented.