Jianpeng Gao, Liang Sheng, Xinyi Wang, Yanhong Zhang, Liang Li, Baojun Duan, Mei Zhang, Yang Li, Dongwei Hei
Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights into the generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of the pulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography 3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are often available for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete data may introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction method using cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. We augment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have been carried out at Qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns between adjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstruction results and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma.
{"title":"Five-view three-dimensional reconstruction for ultrafast dynamic imaging of pulsed radiation sources","authors":"Jianpeng Gao, Liang Sheng, Xinyi Wang, Yanhong Zhang, Liang Li, Baojun Duan, Mei Zhang, Yang Li, Dongwei Hei","doi":"10.1063/5.0177342","DOIUrl":"https://doi.org/10.1063/5.0177342","url":null,"abstract":"Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights into the generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of the pulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography 3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are often available for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete data may introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction method using cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. We augment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have been carried out at Qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns between adjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstruction results and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"128 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139084762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chaoxin Chen, Tao Gong, Zhichao Li, Liang Hao, Yonggang Liu, Xiangming Liu, Hang Zhao, Yaoyuan Liu, Kaiqiang Pan, Qi Li, Sanwei Li, Zhijun Li, Sai Jin, Feng Wang, Dong Yang
In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatial growth of stimulated Brillouin scattering (SBS) in a gas-filled Hohlraum by detecting the SBS-driven ion acoustic wave. High-quality time-resolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on the ray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma; as a result, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-density plasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of the laser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping with the interaction beam.
在 "神光三号 "原型激光设备上进行的一项实验中，通过探测受激布里渊散射（SBS）驱动的离子声波，利用集合汤姆逊散射（TS）来研究充满气体的霍室中受激布里渊散射（SBS）的空间增长。实验中同时获得了高质量的时间分辨 SBS 和 TS 光谱，并通过基于射线追踪模型的稳态代码对其进行了分析。分析表明，离子-离子碰撞可能在抑制金等离子体中的 SBS 生长方面发挥了重要作用；因此，在填充气体区域激发的 SBS 占主导地位。在激光脉冲的早期阶段，SBS 主要来自相互作用光束通道边缘的高密度等离子体，这些等离子体是由相互作用光束加热堆积而成的。在整个激光脉冲持续期间，TS 探头光束的存在可能会扰动与相互作用光束重叠区域周围的密度分布，从而缓解 SBS。
{"title":"Study of the spatial growth of stimulated Brillouin scattering in a gas-filled Hohlraum via detecting the driven ion acoustic wave","authors":"Chaoxin Chen, Tao Gong, Zhichao Li, Liang Hao, Yonggang Liu, Xiangming Liu, Hang Zhao, Yaoyuan Liu, Kaiqiang Pan, Qi Li, Sanwei Li, Zhijun Li, Sai Jin, Feng Wang, Dong Yang","doi":"10.1063/5.0173023","DOIUrl":"https://doi.org/10.1063/5.0173023","url":null,"abstract":"In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatial growth of stimulated Brillouin scattering (SBS) in a gas-filled Hohlraum by detecting the SBS-driven ion acoustic wave. High-quality time-resolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on the ray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma; as a result, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-density plasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of the laser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping with the interaction beam.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"45 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139083550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Relay, for a better MRE!","authors":"Ke Lan","doi":"10.1063/5.0187709","DOIUrl":"https://doi.org/10.1063/5.0187709","url":null,"abstract":"","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"120 37","pages":""},"PeriodicalIF":5.1,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139453919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J.-R. Marquès, L. Lancia, P. Loiseau, P. Forestier-Colleoni, M. Tarisien, E. Atukpor, V. Bagnoud, C. Brabetz, F. Consoli, J. Domange, F. Hannachi, P. Nicolaï, M. Salvadori, B. Zielbauer
We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet [Marquès et al., Phys. Plasmas 28, 023103 (2021)]. In a continuation of this numerical work, we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases: without tailoring, by tailoring only the entrance side of the picosecond laser, and by tailoring both sides of the gas jet. Without tailoring, the acceleration is transverse to the laser axis, with a low-energy exponential spectrum, produced by Coulomb explosion. When the front side of the gas jet is tailored, a forward acceleration appears, which is significantly enhanced when both the front and back sides of the plasma are tailored. This forward acceleration produces higher-energy protons, with a peaked spectrum, and is in good agreement with the mechanism of collisionless shock acceleration (CSA). The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe beam. The refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma tailoring. Comparison with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas jet. These parameters are in good agreement with those required for CSA.
{"title":"Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves","authors":"J.-R. Marquès, L. Lancia, P. Loiseau, P. Forestier-Colleoni, M. Tarisien, E. Atukpor, V. Bagnoud, C. Brabetz, F. Consoli, J. Domange, F. Hannachi, P. Nicolaï, M. Salvadori, B. Zielbauer","doi":"10.1063/5.0178253","DOIUrl":"https://doi.org/10.1063/5.0178253","url":null,"abstract":"We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet [Marquès et al., Phys. Plasmas 28, 023103 (2021)]. In a continuation of this numerical work, we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases: without tailoring, by tailoring only the entrance side of the picosecond laser, and by tailoring both sides of the gas jet. Without tailoring, the acceleration is transverse to the laser axis, with a low-energy exponential spectrum, produced by Coulomb explosion. When the front side of the gas jet is tailored, a forward acceleration appears, which is significantly enhanced when both the front and back sides of the plasma are tailored. This forward acceleration produces higher-energy protons, with a peaked spectrum, and is in good agreement with the mechanism of collisionless shock acceleration (CSA). The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe beam. The refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma tailoring. Comparison with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas jet. These parameters are in good agreement with those required for CSA.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"41 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139031811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Philip Dalladay-Simpson, Bartomeu Monserrat, Li Zhang, Federico Gorelli
Evidence for metallization in dense oxygen has been reported for over 30 years [Desgreniers et al., J. Phys. Chem. 94, 1117 (1990)] at a now routinely accessible 95 GPa [Shimizu et al., Nature 393, 767 (1998)]. However, despite the longevity of this result and the technological advances since, the nature of the metallic phase remains poorly constrained [Akahama et al., Phys. Rev. Lett. 74, 4690 (1995); Goncharov et al., Phys. Rev. B 68, 224108 (2003); Ma, Phys. Rev. B 76, 064101 (2007); and Weck et al., Phys. Rev. Lett. 102, 255503 (2009)]. In this work, through Raman spectroscopy, we report the distinct vibrational characteristics of metallic ζ-O2 from 85 to 225 GPa. In comparison with numerical simulations, we find reasonable agreement with the C2/m candidate structure up to about 150 GPa. At higher pressures, the C2/m structure is found to be unstable and incompatible with experimental observations. Alternative candidate structures, C2/c and Ci, with only two molecules in the primitive unit cell, are found to be stable and more compatible with measurements above 175 GPa, indicative of the dissociation of (O2)4 units. Further, we report and discuss a strong hysteresis and metastability with the precursory phase ϵ-O2. These findings will reinvigorate experimental and theoretical work into the dense oxygen system, which will have importance for oxygen-bearing chemistry, prevalent in the deep Earth, as well as fundamental physics.
{"title":"Distinct vibrational signatures and complex phase behavior in metallic oxygen","authors":"Philip Dalladay-Simpson, Bartomeu Monserrat, Li Zhang, Federico Gorelli","doi":"10.1063/5.0160060","DOIUrl":"https://doi.org/10.1063/5.0160060","url":null,"abstract":"Evidence for metallization in dense oxygen has been reported for over 30 years [Desgreniers et al., J. Phys. Chem. 94, 1117 (1990)] at a now routinely accessible 95 GPa [Shimizu et al., Nature 393, 767 (1998)]. However, despite the longevity of this result and the technological advances since, the nature of the metallic phase remains poorly constrained [Akahama et al., Phys. Rev. Lett. 74, 4690 (1995); Goncharov et al., Phys. Rev. B 68, 224108 (2003); Ma, Phys. Rev. B 76, 064101 (2007); and Weck et al., Phys. Rev. Lett. 102, 255503 (2009)]. In this work, through Raman spectroscopy, we report the distinct vibrational characteristics of metallic ζ-O2 from 85 to 225 GPa. In comparison with numerical simulations, we find reasonable agreement with the C2/m candidate structure up to about 150 GPa. At higher pressures, the C2/m structure is found to be unstable and incompatible with experimental observations. Alternative candidate structures, C2/c and Ci, with only two molecules in the primitive unit cell, are found to be stable and more compatible with measurements above 175 GPa, indicative of the dissociation of (O2)4 units. Further, we report and discuss a strong hysteresis and metastability with the precursory phase ϵ-O2. These findings will reinvigorate experimental and theoretical work into the dense oxygen system, which will have importance for oxygen-bearing chemistry, prevalent in the deep Earth, as well as fundamental physics.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"40 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138688556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Q. Wang, J. J. Honrubia, Y. Yin, X. H. Yang, F. Q. Shao
The Brown–Preston–Singleton (BPS) stopping power model is added to our previously developed hybrid code to model ion beam–plasma interaction. Hybrid simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target, in which they compete with each other. When the target is not completely ionized, the self-generated resistive field effect dominates over the ion scattering effect. However, when the target is completely ionized, this situation is reversed. Moreover, it is found that Ohmic heating is important for higher current densities and materials with high resistivity. The energy fraction deposited as Ohmic heating can be as high as 20%–30%. Typical ion divergences with half-angles of about 5°–10° will modify the proton energy deposition substantially and should be taken into account.
{"title":"Resistive field generation in intense proton beam interaction with solid targets","authors":"W. Q. Wang, J. J. Honrubia, Y. Yin, X. H. Yang, F. Q. Shao","doi":"10.1063/5.0172035","DOIUrl":"https://doi.org/10.1063/5.0172035","url":null,"abstract":"The Brown–Preston–Singleton (BPS) stopping power model is added to our previously developed hybrid code to model ion beam–plasma interaction. Hybrid simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target, in which they compete with each other. When the target is not completely ionized, the self-generated resistive field effect dominates over the ion scattering effect. However, when the target is completely ionized, this situation is reversed. Moreover, it is found that Ohmic heating is important for higher current densities and materials with high resistivity. The energy fraction deposited as Ohmic heating can be as high as 20%–30%. Typical ion divergences with half-angles of about 5°–10° will modify the proton energy deposition substantially and should be taken into account.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"53 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138546926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Since the discovery of hydride superconductors, a significant challenge has been to reduce the pressure required for their stabilization. In this context, we propose that alloying could be an effective strategy to achieve this. We focus on a series of alloyed hydrides with the AMH6 composition, which can be made via alloying A15 AH3 (A = Al or Ga) with M (M = a group ⅢB or IVB metal), and study their behavior under pressure. Seven of them are predicted to maintain the A15-type structure, similar to AH3 under pressure, providing a platform for studying the effects of alloying on the stability and superconductivity of AH3. Among these, the A15-type phases of AlZrH6 and AlHfH6 are found to be thermodynamically stable in the pressure ranges of 40–150 and 30–181 GPa, respectively. Furthermore, they remain dynamically stable at even lower pressures, as low as 13 GPa for AlZrH6 and 6 GPa for AlHfH6. These pressures are significantly lower than that required for stabilizing A15 AlH3. Additionally, the introduction of Zr or Hf increases the electronic density of states at the Fermi level compared with AlH3. This enhancement leads to higher critical temperatures (Tc) of 75 and 76 K for AlZrH6 and AlHfH6 at 20 and 10 GPa, respectively. In the case of GaMH6 alloys, where M represents Sc, Ti, Zr, or Hf, these metals reinforce the stability of the A15-type structure and reduce the lowest thermodynamically stable pressure for GaH3 from 160 GPa to 116, 95, 80, and 85 GPa, respectively. Particularly noteworthy are the A15-type GaMH6 alloys, which remain dynamically stable at low pressures of 97, 28, 5, and 6 GPa, simultaneously exhibiting high Tc of 88, 39, 70, and 49 K at 100, 35, 10, and 10 GPa, respectively. Overall, these findings enrich the family of A15-type superconductors and provide insights for the future exploration of high-temperature hydride superconductors that can be stabilized at lower pressures.
{"title":"Design of high-temperature superconductors at moderate pressures by alloying AlH3 or GaH3","authors":"Xiaowei Liang, Xudong Wei, Eva Zurek, Aitor Bergara, Peifang Li, Guoying Gao, Yongjun Tian","doi":"10.1063/5.0159590","DOIUrl":"https://doi.org/10.1063/5.0159590","url":null,"abstract":"Since the discovery of hydride superconductors, a significant challenge has been to reduce the pressure required for their stabilization. In this context, we propose that alloying could be an effective strategy to achieve this. We focus on a series of alloyed hydrides with the AMH6 composition, which can be made via alloying A15 AH3 (A = Al or Ga) with M (M = a group ⅢB or IVB metal), and study their behavior under pressure. Seven of them are predicted to maintain the A15-type structure, similar to AH3 under pressure, providing a platform for studying the effects of alloying on the stability and superconductivity of AH3. Among these, the A15-type phases of AlZrH6 and AlHfH6 are found to be thermodynamically stable in the pressure ranges of 40–150 and 30–181 GPa, respectively. Furthermore, they remain dynamically stable at even lower pressures, as low as 13 GPa for AlZrH6 and 6 GPa for AlHfH6. These pressures are significantly lower than that required for stabilizing A15 AlH3. Additionally, the introduction of Zr or Hf increases the electronic density of states at the Fermi level compared with AlH3. This enhancement leads to higher critical temperatures (Tc) of 75 and 76 K for AlZrH6 and AlHfH6 at 20 and 10 GPa, respectively. In the case of GaMH6 alloys, where M represents Sc, Ti, Zr, or Hf, these metals reinforce the stability of the A15-type structure and reduce the lowest thermodynamically stable pressure for GaH3 from 160 GPa to 116, 95, 80, and 85 GPa, respectively. Particularly noteworthy are the A15-type GaMH6 alloys, which remain dynamically stable at low pressures of 97, 28, 5, and 6 GPa, simultaneously exhibiting high Tc of 88, 39, 70, and 49 K at 100, 35, 10, and 10 GPa, respectively. Overall, these findings enrich the family of A15-type superconductors and provide insights for the future exploration of high-temperature hydride superconductors that can be stabilized at lower pressures.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"31 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138537070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peipei Wang, Honghai An, Zhiheng Fang, Jun Xiong, Zhiyong Xie, Chen Wang, Zhiyu He, Guo Jia, Ruirong Wang, Shu Zheng, Lan Xia, Wei Feng, Haitao Shi, Wei Wang, Jinren Sun, Yanqi Gao, Sizu Fu
The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions (LPIs). In this study, several preliminary experiments into broadband-laser-driven LPIs are carried out using a newly established hundreds-of-joules broadband second-harmonic-generation laser facility. Through direct comparison with LPI results for a traditional narrowband laser, the actual LPI-suppression effect of the broadband laser is shown. The broadband laser had a clear suppressive effect on both back-stimulated Raman scattering and back-stimulated Brillouin scattering at laser intensities below 1 × 1015 W cm−2. An abnormal hot-electron phenomenon is also investigated, using targets of different thicknesses.
宽带激光技术是抑制激光等离子体相互作用(lpi)过程的一种新方法。在这项研究中，使用新建立的数百焦耳宽带二次谐波产生激光设备进行了宽带激光驱动lpi的几个初步实验。通过与传统窄带激光器的LPI结果的直接比较，展示了宽带激光器抑制LPI的实际效果。在激光强度低于1 × 1015 W cm−2时，宽带激光器对背激拉曼散射和背激布里渊散射均有明显的抑制作用。利用不同厚度的靶材，研究了异常热电子现象。
{"title":"Backward scattering of laser plasma interactions from hundreds-of-joules broadband laser on thick target","authors":"Peipei Wang, Honghai An, Zhiheng Fang, Jun Xiong, Zhiyong Xie, Chen Wang, Zhiyu He, Guo Jia, Ruirong Wang, Shu Zheng, Lan Xia, Wei Feng, Haitao Shi, Wei Wang, Jinren Sun, Yanqi Gao, Sizu Fu","doi":"10.1063/5.0122406","DOIUrl":"https://doi.org/10.1063/5.0122406","url":null,"abstract":"The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions (LPIs). In this study, several preliminary experiments into broadband-laser-driven LPIs are carried out using a newly established hundreds-of-joules broadband second-harmonic-generation laser facility. Through direct comparison with LPI results for a traditional narrowband laser, the actual LPI-suppression effect of the broadband laser is shown. The broadband laser had a clear suppressive effect on both back-stimulated Raman scattering and back-stimulated Brillouin scattering at laser intensities below 1 × 1015 W cm−2. An abnormal hot-electron phenomenon is also investigated, using targets of different thicknesses.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"61 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138537061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Extrapolation of implosion performance between different laser energy scales is investigated for indirect drive through a semi-hydro-equivalent design. Since radiation transport is non-hydro-equivalent, the peak radiation temperature of the hohlraum and the ablation velocity of the capsule ablator are not scale-invariant when the sizes of the hohlraum and the capsule are scale-varied. A semi-hydro-equivalent design method that keeps the implosion velocity Vi, adiabat αF, and PL/Rhc2 (where PL is the laser power and Rhc is the hohlraum and capsule scale length) scale-invariant, is proposed to create hydrodynamically similar implosions. The semi-hydro-equivalent design and the scaled implosion performance are investigated for the 100 kJ Laser Facility (100 kJ-scale) and the National Ignition Facility (NIF-scale) with about 2 MJ laser energy. It is found that the one-dimensional implosion performance is approximately hydro-equivalent when Vi and αF are kept the same. Owing to the non-hydro-equivalent radiation transport, the yield-over-clean without α-particle heating (YOCnoα) is slightly lower at 100 kJ-scale than at NIF-scale for the same scaled radiation asymmetry or the same initial perturbation of the hydrodynamic instability. The overall scaled two-dimensional implosion performance is slightly lower at 100 kJ-scale. The general Lawson criterion factor scales as χnoα2D∼S1.06±0.04 (where S is the scale-variation factor) for the semi-hydro-equivalent implosion design with a moderate YOCnoα. Our study indicates that χnoα ≈ 0.379 is the minimum requirement for the 100 kJ-scale implosion to demonstrate the ability to achieve marginal ignition at NIF-scale.
{"title":"Semi-hydro-equivalent design and performance extrapolation between 100 kJ-scale and NIF-scale indirect drive implosion","authors":"Huasen Zhang, Dongguo Kang, Changshu Wu, Liang Hao, Hao Shen, Shiyang Zou, Shaoping Zhu, Yongkun Ding","doi":"10.1063/5.0150343","DOIUrl":"https://doi.org/10.1063/5.0150343","url":null,"abstract":"Extrapolation of implosion performance between different laser energy scales is investigated for indirect drive through a semi-hydro-equivalent design. Since radiation transport is non-hydro-equivalent, the peak radiation temperature of the hohlraum and the ablation velocity of the capsule ablator are not scale-invariant when the sizes of the hohlraum and the capsule are scale-varied. A semi-hydro-equivalent design method that keeps the implosion velocity Vi, adiabat αF, and PL/Rhc2 (where PL is the laser power and Rhc is the hohlraum and capsule scale length) scale-invariant, is proposed to create hydrodynamically similar implosions. The semi-hydro-equivalent design and the scaled implosion performance are investigated for the 100 kJ Laser Facility (100 kJ-scale) and the National Ignition Facility (NIF-scale) with about 2 MJ laser energy. It is found that the one-dimensional implosion performance is approximately hydro-equivalent when Vi and αF are kept the same. Owing to the non-hydro-equivalent radiation transport, the yield-over-clean without α-particle heating (YOCnoα) is slightly lower at 100 kJ-scale than at NIF-scale for the same scaled radiation asymmetry or the same initial perturbation of the hydrodynamic instability. The overall scaled two-dimensional implosion performance is slightly lower at 100 kJ-scale. The general Lawson criterion factor scales as χnoα2D∼S1.06±0.04 (where S is the scale-variation factor) for the semi-hydro-equivalent implosion design with a moderate YOCnoα. Our study indicates that χnoα ≈ 0.379 is the minimum requirement for the 100 kJ-scale implosion to demonstrate the ability to achieve marginal ignition at NIF-scale.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"254 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138537071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Constantin Aniculaesei, Thanh Ha, Samuel Yoffe, Lance Labun, Stephen Milton, Edward McCary, Michael M. Spinks, Hernan J. Quevedo, Ou Z. Labun, Ritwik Sain, Andrea Hannasch, Rafal Zgadzaj, Isabella Pagano, Jose A. Franco-Altamirano, Martin L. Ringuette, Erhart Gaul, Scott V. Luedtke, Ganesh Tiwari, Bernhard Ersfeld, Enrico Brunetti, Hartmut Ruhl, Todd Ditmire, Sandra Bruce, Michael E. Donovan, Michael C. Downer, Dino A. Jaroszynski, Bjorn Manuel Hegelich
An intense laser pulse focused onto a plasma can excite nonlinear plasma waves. Under appropriate conditions, electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic velocities. This scheme is called a laser wakefield accelerator. In this work, we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the wakefields. We find that a 10-cm-long, nanoparticle-assisted laser wakefield accelerator can generate 340 pC, 10 ± 1.86 GeV electron bunches with a 3.4 GeV rms convolved energy spread and a 0.9 mrad rms divergence. It can also produce bunches with lower energies in the 4–6 GeV range.
{"title":"The acceleration of a high-charge electron bunch to 10 GeV in a 10-cm nanoparticle-assisted wakefield accelerator","authors":"Constantin Aniculaesei, Thanh Ha, Samuel Yoffe, Lance Labun, Stephen Milton, Edward McCary, Michael M. Spinks, Hernan J. Quevedo, Ou Z. Labun, Ritwik Sain, Andrea Hannasch, Rafal Zgadzaj, Isabella Pagano, Jose A. Franco-Altamirano, Martin L. Ringuette, Erhart Gaul, Scott V. Luedtke, Ganesh Tiwari, Bernhard Ersfeld, Enrico Brunetti, Hartmut Ruhl, Todd Ditmire, Sandra Bruce, Michael E. Donovan, Michael C. Downer, Dino A. Jaroszynski, Bjorn Manuel Hegelich","doi":"10.1063/5.0161687","DOIUrl":"https://doi.org/10.1063/5.0161687","url":null,"abstract":"An intense laser pulse focused onto a plasma can excite nonlinear plasma waves. Under appropriate conditions, electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic velocities. This scheme is called a laser wakefield accelerator. In this work, we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the wakefields. We find that a 10-cm-long, nanoparticle-assisted laser wakefield accelerator can generate 340 pC, 10 ± 1.86 GeV electron bunches with a 3.4 GeV rms convolved energy spread and a 0.9 mrad rms divergence. It can also produce bunches with lower energies in the 4–6 GeV range.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"45 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138537069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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