A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 ...A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 m/s to 2500 m/s) can be measured in the HL-1M tokamak fueling experiments. By analyzing photographs and the conditions of frozen pellets (including gas supply, gas replenishment, temperature controlling etc), the pellet-freezing technology is summarized in the paper.展开更多
A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are introduced.The assembly is based on a multi-target rotating wheel capable of hosting mor...A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are introduced.The assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3D motorized stage to allow rapid replenishment and alignment of the target material between laser irradiations.The automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 Hz.Stable and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.展开更多
The roles of laser-induced defects and native defects in multilayer mirrors under multi-shot irradiation condition are investigated. The HfO2/SiO2 dielectric mirrors are deposited by electron beam evaporation （EBE）....The roles of laser-induced defects and native defects in multilayer mirrors under multi-shot irradiation condition are investigated. The HfO2/SiO2 dielectric mirrors are deposited by electron beam evaporation （EBE）. Laser damage testing is carried out on both the 1-on-1 and S-on-1 regimes using 355-nm pulsed laser at a duration of 8 ns. It is found that the single-shot laser-induced damage threshold （LIDT） is much higher than the multi-shot LIDT. In the multi-shot mode, the main factor influencing LIDT is the accumulation of irreversible laser-induced defects and native defects. The surface morphologies of the samples are observed by optical microscopy. Moreover, the number of laser-induced defects affects the damage probability of the samples. A correlative model based on critical conduction band （CB） electron density （ED） is presented to simulate the multi-shot damage behavior.展开更多
文摘A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 m/s to 2500 m/s) can be measured in the HL-1M tokamak fueling experiments. By analyzing photographs and the conditions of frozen pellets (including gas supply, gas replenishment, temperature controlling etc), the pellet-freezing technology is summarized in the paper.
基金This work was supportedby the Spanish Ministerio de Ciencia,Innovacion y Universidades under grants RTI2018-101578-B-C21,RTI2018-101578-B-C22,FPI predoctorals BES-2017-08917 and PRE2019-090730Unidad de Excelencia Maria de Maetzu under project MdM-2016-0692-17-2+2 种基金the Xuntade Galicia grants GRC ED431C 2017/54 and ED431F2023/21 and a grant of the program Grupos de investigacion consolidados(CIAICO/2022/008)financed by Generalitat Valenciana.Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional(FEDER)of the Comunitat Valenciana 2014-2020(IDIFEDER/2021/002)This work was supported by‘la Caixa'Foundation(ID 100010434)(fellowship code LCF/BQ/PI20/11760027)grant RYC2021-032654-I funded by MICIU/AEI/10.13039/501100011033 and by‘European Union NextGenerationEU'.
文摘A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are introduced.The assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3D motorized stage to allow rapid replenishment and alignment of the target material between laser irradiations.The automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 Hz.Stable and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.
文摘The roles of laser-induced defects and native defects in multilayer mirrors under multi-shot irradiation condition are investigated. The HfO2/SiO2 dielectric mirrors are deposited by electron beam evaporation （EBE）. Laser damage testing is carried out on both the 1-on-1 and S-on-1 regimes using 355-nm pulsed laser at a duration of 8 ns. It is found that the single-shot laser-induced damage threshold （LIDT） is much higher than the multi-shot LIDT. In the multi-shot mode, the main factor influencing LIDT is the accumulation of irreversible laser-induced defects and native defects. The surface morphologies of the samples are observed by optical microscopy. Moreover, the number of laser-induced defects affects the damage probability of the samples. A correlative model based on critical conduction band （CB） electron density （ED） is presented to simulate the multi-shot damage behavior.
