Temporal,spectral and spatial characters of 0.3-nm-bandwidth high-energy laser pulse propagating through a long path are studied in detail in one newly constructed beamline of our laser facility.The evolution of propa...Temporal,spectral and spatial characters of 0.3-nm-bandwidth high-energy laser pulse propagating through a long path are studied in detail in one newly constructed beamline of our laser facility.The evolution of propagation,pulse energy and near-field deterioration are analyzed theoretically and experimentally.Substituting argon for air is demonstrated effectively to suppress stimulated rotational Raman scattering and the experimental result provides operating criterion,and engineering parameters for the under-constructed beamlines.展开更多
Low density and low convergence implosion occurs in the exploding-pusher target experiment, and generates neutrons isotropically to develop a high yield platform.In order to validate the performance of ShenGuang(SG) l...Low density and low convergence implosion occurs in the exploding-pusher target experiment, and generates neutrons isotropically to develop a high yield platform.In order to validate the performance of ShenGuang(SG) laser facility and test nuclear diagnostics, all 48-beam lasers with an on-target energy of 48 kJ were firstly used to drive room-temperature, DT gas-filled glass targets.The optimization has been carried out and optimal drive uniformity was obtained by the combination of beam repointing and target.The final irradiation uniformity of less than 5% on polar direct-drive capsules of 540 μm in diameter was achieved, and the highest thermonuclear yield of the polar direct-drive DT fuel implosion at the SG was 1.04 × 10^(13).The experiment results show neutron yields severely depend on the irradiation uniformity and laser timing,and decrease with the increase of the diameter and fuel pressure of the target.The thin CH ablator does not impact the implosion performance, but the laser drive uniformity is important.The simulated results validate that the cos γ distribution laser design is reasonable and can achieve a symmetric pressure distribution.Further optimization will focus on measuring the symmetry of the hot spot by self-emission imaging, increasing the diameter, and decreasing the fuel pressure.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61205110the Key Laboratory Foundation of China Academy of Engineering Physics(No 9140C680301100C6806)the Innovation Foundation of Laser Fusion Research Center.
文摘Temporal,spectral and spatial characters of 0.3-nm-bandwidth high-energy laser pulse propagating through a long path are studied in detail in one newly constructed beamline of our laser facility.The evolution of propagation,pulse energy and near-field deterioration are analyzed theoretically and experimentally.Substituting argon for air is demonstrated effectively to suppress stimulated rotational Raman scattering and the experimental result provides operating criterion,and engineering parameters for the under-constructed beamlines.
基金Project supported by the National Natural Science Foundation of China(Grant No.11605178)the Science Challenging Project,China(Grant Nos.JCKY2016212A505 and TZ2016001)
文摘Low density and low convergence implosion occurs in the exploding-pusher target experiment, and generates neutrons isotropically to develop a high yield platform.In order to validate the performance of ShenGuang(SG) laser facility and test nuclear diagnostics, all 48-beam lasers with an on-target energy of 48 kJ were firstly used to drive room-temperature, DT gas-filled glass targets.The optimization has been carried out and optimal drive uniformity was obtained by the combination of beam repointing and target.The final irradiation uniformity of less than 5% on polar direct-drive capsules of 540 μm in diameter was achieved, and the highest thermonuclear yield of the polar direct-drive DT fuel implosion at the SG was 1.04 × 10^(13).The experiment results show neutron yields severely depend on the irradiation uniformity and laser timing,and decrease with the increase of the diameter and fuel pressure of the target.The thin CH ablator does not impact the implosion performance, but the laser drive uniformity is important.The simulated results validate that the cos γ distribution laser design is reasonable and can achieve a symmetric pressure distribution.Further optimization will focus on measuring the symmetry of the hot spot by self-emission imaging, increasing the diameter, and decreasing the fuel pressure.
