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1.
Progress in direct-drive inertial confinement fusion research at the
laboratory for laser energetics
R. L. McCrory D. D. Meyerhofer S. J. Loucks S. Skupsky R. Betti T. R. Boehly T. J.B. Collins R. S. Craxton J. A. Delettrez D. H. Edgell R. Epstein K. A. Fletcher C. Freeman J. A. Frenje V. Yu. Glebov V. N. Goncharov D. R. Harding I. V. Igumenshchev R. L. Keck J. D. Kilkenny J. P. Knauer C. K. Li J. Marciante J. A. Marozas F. J. Marshall A. V. Maximov P. W. McKenty S. F.B. Morse J. Myatt S. Padalino R. D. Petrasso P. B. Radha S. P. Regan T. C. Sangster F. H. Séguin W. Seka V. A. Smalyuk J. M. Soures C. Stoeckl B. Yaakobi J. D. Zuegel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):233-238
Direct-drive inertial confinement fusion (ICF) is
expected to demonstrate high gain on the National Ignition Facility (NIF) in
the next decade and is a leading candidate for inertial fusion energy
production. The demonstration of high areal densities in hydrodynamically
scaled cryogenic DT or D2 implosions with neutron yields that are a
significant fraction of the “clean” 1-D predictions will validate the
ignition-equivalent direct-drive target performance on the OMEGA laser at
the Laboratory for Laser Energetics (LLE). This paper highlights the
recent experimental and theoretical progress leading toward achieving this
validation in the next few years.
The NIF will initially be configured for X-ray drive and with no beams
placed at the target equator to provide a symmetric irradiation of a
direct-drive capsule. LLE is developing the “polar-direct-drive” (PDD)
approach that repoints beams toward the target equator. Initial 2-D
simulations have shown ignition. A unique “Saturn-like” plastic ring
around the equator refracts the laser light incident near the equator toward
the target, improving the drive uniformity.
LLE is currently constructing the multibeam, 2.6-kJ/beam, petawatt laser
system OMEGA EP. Integrated fast-ignition experiments, combining the OMEGA
EP and OMEGA Laser Systems, will begin in FY08. 相似文献
2.
P. A. Holstein M. Casanova A. Casner C. Cherfils E. Dattolo L. Disdier D. Galmiche J. Giorla M. Houry J. P. Jadaud S. Laffite S. Liberatore P. Loiseau L. Lours L. Masse M. C. Monteil O. Morice M. Naudy F. Philippe F. Poggi F. Renaud G. Riazuelo Y. Saillard P. Seytor M. Vandenboomgaerde F. Wagon 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):239-247
This article sums up the theoretical and experimental studies about
ignition. Three experiments are salient this year on the Omega laser in
collaboration with DOE laboratories (1) 3 cones of beams allow to mimic the
LMJ configuration and to get symmetry measurements. (2) We measured
perturbations due to hydro-instability in CHGe planar samples with face-on
and side-on radiographs. (3) We improved our nuclear diagnostics,
particularly the neutron image system tested on direct drive implosions. As far as LMJ target design is concerned, we defined
a preliminary domain
corresponding to the possible operation at 2ω. At 3ω we studied the low mode
instability effects on the DT deformation (due to the laser or to the
target) and on the yield. The stability is clearly improved with graded
doped CH for our nominal capsule L1215. 相似文献
3.
S. W. Haan M. C. Herrmann J. D. Salmonson P. A. Amendt D. A. Callahan T. R. Dittrich M. J. Edwards O. S. Jones M. M. Marinak D. H. Munro S. M. Pollaine B. K. Spears L. J. Suter 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):249-258
Targets intended to produce ignition on NIF are being simulated and the simulations are used to set specifications for target
fabrication and other program elements. Recent design work has focused on designs that assume only 1.0 MJ of laser energy
instead of the previous 1.6 MJ. To perform with less laser energy, the hohlraum has been redesigned to be more efficient than
previously, and the capsules are slightly smaller. Three hohlraum designs are being examined: gas fill, SiO2 foam fill, and SiO2 lined. All have a cocktail wall, and shields mounted between the capsule and the laser entrance holes. Two capsule designs
are being considered. One has a graded doped Be(Cu) ablator, and the other graded doped CH(Ge). Both can perform acceptably
with recently demonstrated ice layer quality, and with recently demonstrated outer surface roughness. Complete tables of specifications
are being prepared for both targets, to be completed this fiscal year. All the specifications are being rolled together into
an error budget indicating adequate margin for ignition with the new designs. The dominant source of error is hohlraum asymmetry
at intermediate modes 4–8, indicating the importance of experimental techniques to measure and control this asymmetry. 相似文献
4.
Review of Japanese fusion program and role of inertial fusion 总被引:1,自引:0,他引:1
O. Motojima 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):219-225
The high compression of 600 times liquid density and the recent fast heating of a compressed core to 1-keV temperature have
provided proof-of-principle of the fast ignition concept, and these results have significantly contributed to approve first
phase of the Fast Ignition Realization EXperiment (FIREX) project. The goal of FIREX-I is to demonstrate fast heating of a
fusion fuel up to the ignition temperature of 5–10 keV. Although the fuel size of FIREX-I is too small to ignite, sufficient
heating will provide the scientific viability of ignition-and-burn by increasing the laser energy thereby the fuel size. Based
on the result of FIREX-I, the decision of the start of FIREX-II to achieve ignition-and-burn can be made. The FIREX program
is under the collaboration of the Institute of Laser Engineering and the National Institute for Fusion Science. 相似文献
5.
D. Besnard 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):207-213
The French Commissariat à l'énergie Atomique (CEA) is
currently building the Laser MegaJoule (LMJ), a 240-beam laser facility, at
the CEA Laboratory CESTA near Bordeaux. LMJ will be a cornerstone of CEA's
“Programme Simulation”, the French Stockpile Stewardship Program. LMJ is
designed to deliver about 2 MJ of 0.35 μm light to targets for high
energy density physics experiments, among which fusion experiments. LMJ
technological choices were validated with the Ligne d'Intégration Laser
(LIL), a scale 1 prototype of one LMJ bundle, built at CEA/CESTA. Plasma
experiments started at the end of 2004 on LIL, which is already open to the
scientific community through the Plasma and Lasers Institute. The
construction of the LMJ building itself started in March of 2003. LMJ will
be gradually commissioned from early 2011, and after an experimental program
to progress toward fusion, the first fusion experiments will begin late
2012. 相似文献
6.
蒲昱东 陈伯伦 黄天晅 缪文勇 陈家斌 张继彦 杨国洪 易荣清 韦敏习 杜华冰 彭晓世 余波 蒋炜 晏骥 景龙飞 唐琦 宋仔峰 江少恩 杨家敏 刘慎业 丁永坤 《强激光与粒子束》2015,27(03):032015
激光间接驱动惯性约束聚变利用辐射烧蚀驱动靶丸球形内爆,在减速阶段将内爆动能转化成热斑内能,同时压缩燃料,达到点火条件,实现聚变点火。根据目前认识,影响内爆压缩过程的主要因素包括内爆对称性、燃料熵增因子、内爆速度和混合。内爆物理实验研究的目的是发展对上述影响因素的实验表征方法,获取这些影响因素随靶设计参数的变化规律,建立相应的实验调控能力,最终达到不断提升内爆性能的目的。为此,在内爆对称性方面,开展了Bi球自发光实验,用于研究点火脉冲前2 ns驱动不对称性;在内爆速度方面,开展了球面弯晶单能流线实验,测量得到内爆速度和剩余质量随时间的变化;在混合方面,开展了内壳层示踪涂层内爆混合实验,测量得到环形发光图像。为考察综合内爆性能,在神光Ⅱ和神光Ⅲ原型装置上开展了DT内爆实验,获得了中子产额随初始靶参数的变化规律。 相似文献
7.
J. D. Kilkenny 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):289-292
The USA Inertial Confinement Fusion (ICF) Program evolved
from the Nuclear Test Program which had restricted shot opportunities for
experimentalists to develop sophisticated experimental techniques. In
contrast the ICF program in the US was able to increase the shot
availability on its large facilities, and develop sophisticated targets and
diagnostics to measure and understand the properties of the high energy
density plasmas (HEDP) formed. Illustrative aspects of this evolution at
Lawrence Livermore National Laboratory (LLNL), with examples of the
development of diagnostics and target fabrication are described. 相似文献
8.
A first set of shock timing, laser-plasma interaction, hohlraum energetics
and hydrodynamic experiments have been performed using the first 4 beams of
the National Ignition Facility (NIF), in support of indirect drive Inertial
Confinement Fusion (ICF) and High Energy Density Physics (HEDP). In
parallel, a robust set of optical and X-ray spectrometers, interferometer,
calorimeters and imagers have been activated. The experiments have been
undertaken with laser powers and energies of up to 8 TW and 17 kJ in flattop
and shaped 1–9 ns pulses focused with various beam smoothing options. The
experiments have demonstrated excellent agreement between measured and
predicted laser-target coupling in foils and hohlraums, even when extended
to a longer pulse regime unattainable at previous laser facilities,
validated the predicted effects of beam smoothing on intense laser beam
propagation in long scale-length plasmas and begun to test 3D codes by
extending the study of laser driven hydrodynamic jets to 3D geometries. 相似文献
9.
李志超 赵航 龚韬 李欣 杨冬 蒋小华 郑坚 刘永刚 刘耀远 陈朝鑫 李三伟 李琦 潘凯强 郭亮 理玉龙 徐涛 彭晓世 吴畅书 张桦森 郝亮 蓝可 陈耀桦 郑春阳 古培俊 王峰 蔡洪波 郑无敌 邹士阳 杨家敏 江少恩 张保汉 朱少平 丁永坤 《强激光与粒子束》2020,32(9):092004-1-092004-14
当前,激光惯性约束聚变在越来越接近点火的极端能量密度条件下,实验与模拟的偏离逐渐增大,一个关键原因是缺乏对黑腔等离子体状态及其影响黑腔能量学和内爆对称性的细致研究和判断。光学汤姆逊散射主动式、诊断精确、参数完备的优点,使之成为激光惯性约束聚变黑腔等离子体状态参数精密诊断的标准方法。中国面向激光惯性约束聚变研究的光学汤姆逊散射实验技术的发展与神光系列激光装置的建设和在其上开展的物理实验紧密相关。近年来,四倍频汤姆逊散射实验技术在神光III原型和100 kJ激光装置上相继建立,部分实验结果不仅加深了对激光惯性约束聚变靶物理的认识,还反映了实验条件对汤姆逊散射诊断的影响,促进了实验技术的精密化发展。在未来,还需要进一步发展多支路汤姆逊散射、五倍频汤姆逊散射和超热相干汤姆逊散射等新技术,面向点火黑腔条件,大幅提升激光等离子体状态参数的诊断精度,开展新物理机制的探索和研究,在激光惯性约束聚变和其他高能量密度物理科学领域发挥更重要的作用。 相似文献
10.
通过对冲击波点火内爆过程的数值模拟分析点火热斑压缩及形成机制。分析了传统中心点火的内爆过程,热斑主要经历冲击波压缩和惯性压缩过程,点火主要通过惯性压缩来实现。并仔细分析了冲击波点火的内爆压缩过程,从内爆角度来看冲击波点火并不是压缩和点火分开的两步过程,点火冲击波实际参与压缩过程,点火冲击波对热斑的直接影响很有限,热斑仍然主要通过壳层的惯性压缩实现点火。利用惯性压缩的定标关系及冲击波碰撞对壳层影响规律分析了热斑增压的物理机制,冲击波点火是通过点火冲击波与回冲击波的碰撞来提高壳层的密度,从而实现热斑压力的提升。 相似文献
11.
D. H.H. Hoffmann A. Blazevic O. N. Rosmej P. Spiller N. A. Tahir K. Weyrich T. Dafni M. Kuster P. Ni M. Roth S. Udrea D. Varentsov J. Jacoby V. Kain R. Schmidt K. Zioutas V. Mintsev V. E. Fortov B. Yu. Sharkov 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):293-300
Interaction phenomena of intense ion- and laser radiation with matter have a
large range of application in different fields of science, extending from
basic research of plasma properties to applications in energy science,
especially in inertial fusion. The heavy ion synchrotron at GSI now
routinely delivers intense uranium beams that deposit about 1 kJ/g of
specific energy in solid matter, e.g. solid lead. Our simulations show that
the new accelerator complex FAIR (Facility for Antiproton and Ion Research)
at GSI as well as beams from the CERN large hadron collider (LHC) will
vastly extend the accessible parameter range for high energy density states.
A natural example of hot dense plasma is provided by our neighbouring star
the sun, and allows a deep insight into the physics of fusion, the
properties of matter at high energy density, and is moreover an excellent
laboratory for astroparticle physics. As such the sun's interior plasma can
even be used to probe the existence of novel particles and dark matter
candidates. We present an overview on recent results and developments of
dense plasma physics addressed with heavy ion and laser beams combined with
accelerator- and nuclear physics technology. 相似文献
12.
在局域热动平衡近似下, 利用能量平衡关系, 建立热核系统整体点火能量平衡方程, 对该方程求解得到热核反应系统点火阈值. 在计算和分析的基础上给出参数空间的点火关系, 以及该条件受装量、核子数比以及返照率等因素的影响情况. 点火时刻面密度越大, 则对应的点火温度越低, 并且电子-辐射温度脱离越小, 越接近三温平衡的点火状态; 反之则在点火时刻对应较大温度脱离. 更重要的是, 该分析方法还可以根据点火时刻系统的物理状态, 通过线性稳定性分析方法, 描述出系统的后续行为, 也就是说, 可以判断出这样的热核系统能否继续升温并实现深度燃烧. 相似文献
13.
14.
在惯性约束聚变物理研究中,等离子体界面处的动理学效应及其时空演化特性近年来受到重点关注,因为它会显著影响激光能量沉积、激光等离子体不稳定性、辐照对称性、黑腔和内爆性能等诸多物理。准确描绘等离子体特征界面附近的动理学效应是惯性约束聚变物理设计的基本需求,也是高能量密度物理中的具有挑战且未完全解决的问题。重点回顾近几年来本团队围绕等离子体动理学效应及其影响开展的一些研究工作:(1)聚变黑腔中金等离子体与靶丸冕区等离子体边缘处的电场结构及其加速的高能离子对内爆对称性的影响;(2)激光光路上高Z-低Z等离子体界面处的电场产生机制及其导致的反常离子扩散对激光等离子体不稳定性的影响;(3)等离子体中电磁场结构的质子照相反演。 相似文献
15.
激光等离子体相互作用(LPI)和瑞利-泰勒流体不稳定性(RTI)是影响间接驱动惯性约束聚变成功的两个主要不确定性因素。点火黑腔内环激光通道在靠近黑腔壁的区域是内环激光SRS背反产生与发展的主要区域。内环通道在该区域满足通道内外压力平衡和能量平衡条件。据此提出了间接驱动惯性约束聚变点火黑腔等离子体定标关系。结合描述靶丸内爆飞行阶段物理以及内爆性能的两个定标关系,提出了描述稳定性相对性能的指标。该指标可以指导点火靶设计,为LPI和RTI提供需要的裕量空间,是点火阈值因子(ITF)的补充。 相似文献
16.
M. Bonelli A.C. Ferrari A. Fioravanti A. Li Bassi A. Miotello P.M. Ossi 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,25(3):269-280
Tetrahedral amorphous carbon films have been produced by pulsed laser deposition, at a wavelength of 248 nm, ablating highly
oriented pyrolytic graphite at room temperature, in a 10-2 Pa vacuum, at fluences ranging between 0.5 and 35 Jcm-2. Both (100) Si wafers and wafers covered with a SiC polycrystalline interlayer were used as substrates. Film structure was
investigated by Raman spectroscopy at different excitation wavelength from 633 nm to 229 nm and by transmission Electron Energy
Loss Spectroscopy. The films, which are hydrogen-free, as shown by Fourier Transform Infrared Spectroscopy, undergo a transition
from mainly disordered graphitic to up to 80% tetrahedral amorphous carbon (ta-C) above a threshold laser fluence of 5 J cm-2. By X-ray reflectivity roughness, density and cross-sectional layering of selected samples were studied. Film hardness as
high as 70 GPa was obtained by nanoindentation on films deposited with the SiC interlayer. By scratch test film adhesion and
friction coefficients between 0.06 and 0.11 were measured. By profilometry we obtained residual stress values not higher than
2 GPa in as-deposited 80% sp3 ta-C films.
Received 25 June 2001 相似文献