A fast converging sparse reconstruction algorithm in ghost imaging is presented. It utilizes total variation regularization and its formulation is based on the Karush-Kuhn-Tucker (KKT) theorem in the theory of convex ...A fast converging sparse reconstruction algorithm in ghost imaging is presented. It utilizes total variation regularization and its formulation is based on the Karush-Kuhn-Tucker (KKT) theorem in the theory of convex optimization. Tests using experimental data show that, compared with the algorithm of Gradient Projection for Sparse Reconstruction (GPSR), the proposed algorithm yields better results with less computation work.展开更多
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 non...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.展开更多
Line-focused high power laser was used to irradiate a magnesium slab target in order to generate line-shaped laser-plasma.Plasma parameter profile distribution(electron temperature and electron density)on the directio...Line-focused high power laser was used to irradiate a magnesium slab target in order to generate line-shaped laser-plasma.Plasma parameter profile distribution(electron temperature and electron density)on the direction perpendicular to the target surface was obtained by spectroscopic diagnostic method,which is quite different from that of the spot-shaped laser-plasmas.New experimental phenomena that can be interpreted as“plasma satellites”were also observed.展开更多
Shear Alfven waves have been successfully excited in KT-5B small tokamak by means of the one turn longitudinal loop antenna located in the shadow area.The measured antenna loadings show their rich structure,and the lo...Shear Alfven waves have been successfully excited in KT-5B small tokamak by means of the one turn longitudinal loop antenna located in the shadow area.The measured antenna loadings show their rich structure,and the loadings are also found to be sensitive to the plasma current.Preliminary evidence of surface electrostatic wave was observed.展开更多
基金Supported by the Hi-Tech Research and Development Program of China (No. 2011AA120102)
文摘A fast converging sparse reconstruction algorithm in ghost imaging is presented. It utilizes total variation regularization and its formulation is based on the Karush-Kuhn-Tucker (KKT) theorem in the theory of convex optimization. Tests using experimental data show that, compared with the algorithm of Gradient Projection for Sparse Reconstruction (GPSR), the proposed algorithm yields better results with less computation work.
基金Supported by the National Natural High Technology Program.
文摘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.
文摘Line-focused high power laser was used to irradiate a magnesium slab target in order to generate line-shaped laser-plasma.Plasma parameter profile distribution(electron temperature and electron density)on the direction perpendicular to the target surface was obtained by spectroscopic diagnostic method,which is quite different from that of the spot-shaped laser-plasmas.New experimental phenomena that can be interpreted as“plasma satellites”were also observed.
基金Supported by the Doctoral Training Foundation of National Education Commission.
文摘Shear Alfven waves have been successfully excited in KT-5B small tokamak by means of the one turn longitudinal loop antenna located in the shadow area.The measured antenna loadings show their rich structure,and the loadings are also found to be sensitive to the plasma current.Preliminary evidence of surface electrostatic wave was observed.
