J.P. Sauppe, I. Sagert, T.H. Day, K.A. Flippo, J.L. Kline, L. Kot, S. Palaniyappan, R.A. Roycroft, D.W. Schmidt
{"title":"Double cylinder implosion experiments at the National Ignition Facility","authors":"J.P. Sauppe, I. Sagert, T.H. Day, K.A. Flippo, J.L. Kline, L. Kot, S. Palaniyappan, R.A. Roycroft, D.W. Schmidt","doi":"10.1016/j.hedp.2024.101156","DOIUrl":"10.1016/j.hedp.2024.101156","url":null,"abstract":"<div><p>Cylindrical implosion experiments are used to directly measure instability growth in a convergent geometry, providing a wealth of data for model validation. Double cylinders are a natural extension of the platform and enable measurements at a classically unstable interface, the outer surface of the inner cylinder, which experiences no ablative stabilization from the laser drive. However, the utility of this platform relies upon maintaining adequate axial uniformity of the inner cylinder during the implosion. Although previous smaller-scale double cylinder experiments exhibited acceptable levels of axial uniformity, radiation-hydrodynamics simulations of larger-scale double cylinders predict more axial non-uniformity induced by the impedance mismatch as the shock wraps around the axial ends of the inner cylinder. A mechanism to reduce axial non-uniformity in these larger double cylinder implosions is presented, and preliminary experimental data confirms the efficacy of the selected mitigation approach.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101156"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142217056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
K.L. Baker , P.A. Amendt , D.A. Mariscal , H. Sio , O.L. Landen , D.D. Ho , V.A. Smalyuk , J.D. Lindl , J.S. Ross , L. Aghaian , A. Allen , N. Aybar , N.W. Birge , D.T. Casey , P.M. Celliers , H. Chen , T. Fehrenbach , D. Fittinghoff , H. Geppert-Kleinrath , V. Geppert-Kleinrath , C.V. Young
{"title":"Frustraum 1100 experimental campaign on the national ignition facility","authors":"K.L. Baker , P.A. Amendt , D.A. Mariscal , H. Sio , O.L. Landen , D.D. Ho , V.A. Smalyuk , J.D. Lindl , J.S. Ross , L. Aghaian , A. Allen , N. Aybar , N.W. Birge , D.T. Casey , P.M. Celliers , H. Chen , T. Fehrenbach , D. Fittinghoff , H. Geppert-Kleinrath , V. Geppert-Kleinrath , C.V. Young","doi":"10.1016/j.hedp.2024.101158","DOIUrl":"10.1016/j.hedp.2024.101158","url":null,"abstract":"<div><p>We present findings from an experimental tuning campaign aimed at igniting larger DT cryogenic layered implosions using a dual frustum shaped hohlraum, denoted “frustraum”. The frustraum's distinctive shape reduces hohlraum wall losses while concurrently enhancing minimum capsule clearance with the hohlraum wall and sensitivity to pointing changes. Compared to current cylindrical hohlraum (6.4 × 11.24 mm), the frustraum has a wall area approximately 20 % smaller, resulting in a measured improvement in efficiency of around 12 %. Consequently, 12 % less laser energy is required to implode a capsule within the same acceleration timeframe. Conversely, directing the same laser energy into the frustraum yields higher ion temperatures within symmetry capsules, along with increased radiation temperatures and reduced implosion acceleration times compared to current cylindrical hohlraums.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101158"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142267927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Electron impact ionization in dense plasmas","authors":"Walter R. Johnson , Joseph Nilsen , K.T. Cheng","doi":"10.1016/j.hedp.2024.101153","DOIUrl":"10.1016/j.hedp.2024.101153","url":null,"abstract":"<div><p>The distorted-wave with exchange (DWE) method is employed to evaluate electron impact ionization cross sections in dense electron–ion plasmas. Bound and continuum electron wave functions are obtained from a non-relativistic average-atom code. Plots of DWE cross sections are presented for <span><math><mrow><mn>1</mn><mi>s</mi></mrow></math></span> electrons in Li and Be plasmas and <span><math><mrow><mn>2</mn><mi>p</mi></mrow></math></span> electrons in Na and Mg plasmas. For each of these elements, cross sections are evaluated at metallic density in a range of temperatures from 10 to 100 eV and at their respective melting points. Resonances in the cross sections appear near the incident energy threshold at high temperatures. The origin of these resonances is discussed. In general, the distorted wave (DW) method without exchange is found to be a good approximation to the DWE method for electron impact ionization calculations. In the resonance region, however, exchange effects are found to be very important and cannot be neglected.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101153"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142097586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Stable creation of a single plasma channel and collimated fast electrons using large-scale PIC simulations with new dynamic load-balancing technique","authors":"Hideaki Habara , Yoshinori Ueyama , Yutaka Nakamura , Hitoshi Sakagami","doi":"10.1016/j.hedp.2024.101147","DOIUrl":"10.1016/j.hedp.2024.101147","url":null,"abstract":"<div><p>We developed a PIC code using new load balancing technique, in which the lower load processes help the higher load processes. A test calculation indicates more than 10 times faster than that without load balancing. Large scale 3-d calculations indicate the formation of central current whose density is close to critical density, supported by the magnetic field inside the channel.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101147"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1574181824000727/pdfft?md5=b8de97496eff919d4d9acc761c6c39f1&pid=1-s2.0-S1574181824000727-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142097587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"How ignition and target gain >1 were achieved in inertial fusion","authors":"O.A. Hurricane","doi":"10.1016/j.hedp.2024.101157","DOIUrl":"10.1016/j.hedp.2024.101157","url":null,"abstract":"<div><p>For many decades the running joke in fusion research has been that “fusion” is twenty years away and always will be. Yet, in 2023 we find ourselves in a position where we can talk about the milestones of burning plasmas, fusion ignition, and target energy gain greater than unity in the past tense – a situation that is remarkable! This paper tells some of the story of the applied physics challenges that needed to be overcome to achieve these milestones and the strategy our team followed. Things did not always go well and some practical lessons learned are part of this story. The data shows, getting to a burning plasma in late 2020 and early 2021 was a key tipping-point, after which ignition (August 8, 2021) and target gain (December 5, 2022) were rapidly achieved.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101157"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142232468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Extension of the SpK atomic physics code to generate global equation of state data","authors":"Adam R. Fraser , A.J. Crilly , N.-P.L. Niasse , D.A. Chapman , J.D. Pecover , S.J. O’Neill , J.P. Chittenden","doi":"10.1016/j.hedp.2024.101136","DOIUrl":"10.1016/j.hedp.2024.101136","url":null,"abstract":"<div><p>Global microphysics models are required for the modelling of high-energy-density physics (HEDP) experiments, the improvement of which are critical to the path to inertial fusion energy. This work presents further developments to the atomic and microphysics code, <span>SpK</span>, part of the numerical modelling suite of Imperial College London and First Light Fusion. We extend the capabilities of <span>SpK</span> to allow the calculation of the equation of state (EoS). The detailed configuration accounting calculations are interpolated into finite-temperature Thomas–Fermi calculations at high coupling to form the electronic component of the model. The Cowan model provides the ionic contribution, modified to approximate the physics of diatomic molecular dissociation. By utilising bonding corrections and performing a Maxwell construction, <span>SpK</span> captures the EoS from states ranging from the zero-pressure solid, through the liquid–vapour coexistence region and into plasma states. This global approach offers the benefit of capturing electronic shell structure over large regions of parameter space, building highly-resolved tables in minutes on a simple desktop. We present shock Hugoniot and off-Hugoniot calculations for a number of materials, comparing <span>SpK</span> to other models and experimental data. We also apply EoS and opacity data generated by <span>SpK</span> in integrated simulations of indirectly-driven capsule implosions, highlighting physical sensitivities to the choice of EoS models.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101136"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142088906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"A hybrid simulation integrating molecular dynamics and particle-in-cell methods for improved laser-target interaction","authors":"Harihara Sudhan Kumar , Masayuki Takahashi , Yasuhiro Kuramitsu , Takumi Minami , Hiromitsu Kiriyama , Yuji Fukuda , Naofumi Ohnishi","doi":"10.1016/j.hedp.2024.101148","DOIUrl":"10.1016/j.hedp.2024.101148","url":null,"abstract":"<div><p>Ultra-thin targets (less than 10 nm), such as graphene, can be irradiated with relativistic intensity lasers to generate energetic ions. However, the laser prepulse can prematurely destroy these targets and significantly influence the final ion energies. Due to the limitations of the conventional hydrodynamic model, simulating the interaction between ultra-thin targets and a prepulse is infeasible. To overcome this issue, we propose a hybrid simulation technique in this study. This technique involves simulating the target-prepulse interaction using molecular dynamics (MD) simulation, which is then combined with the particle-in-cell simulation for the target-main pulse interaction, in order to accurately model the entire laser-target interaction dynamics. A realistic, experimentally measured laser intensity profile for the prepulse is used for the MD simulation, and the particle energies from this hybrid simulation are found to be in good agreement with the experiment.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101148"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Hermann Geppert-Kleinrath , Robert Dwyer , Kevin Meaney , Cathleen Fry , Yongho Kim
{"title":"Technique for an improved and time-resolved carbon areal density measurement with a single channel diagnostic for inertial confinement fusion","authors":"Hermann Geppert-Kleinrath , Robert Dwyer , Kevin Meaney , Cathleen Fry , Yongho Kim","doi":"10.1016/j.hedp.2024.101145","DOIUrl":"10.1016/j.hedp.2024.101145","url":null,"abstract":"<div><p>Measurement of the areal density and velocity of the carbon ablator shell during peak burn in inertial confinement fusion give powerful information on the state of the ablator and where in the trajectory of implosion it reaches peak burn. Detailed comparison of the absolute densities and velocities of the carbon in implosions has been prevented by the limited ability to resolve shot-to-shot variation within a shot series or within a campaign. A new approach using a single, ultra fast (<span><math><mo>∼</mo></math></span>10 ps) gamma ray channel can massively reduce uncertainties and will provide insights on improvements to target and drive variables. Small improvements in these experimental design parameters may result in much greater yields.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101145"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1574181824000703/pdfft?md5=9d8228163ee7a5b1830e6c1494d1c196&pid=1-s2.0-S1574181824000703-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142162956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexandre Do, Eduard L. Dewald, Marius Millot, Christopher R. Weber, Otto L. Landen, Vladimir A. Smalyuk
{"title":"Study of shocks and ablation front in diamond ablator during a capsule implosion experiment at the National Ignition Facility","authors":"Alexandre Do, Eduard L. Dewald, Marius Millot, Christopher R. Weber, Otto L. Landen, Vladimir A. Smalyuk","doi":"10.1016/j.hedp.2024.101161","DOIUrl":"10.1016/j.hedp.2024.101161","url":null,"abstract":"<div><div>An X-ray phase contrast imaging platform using streaked refraction enhanced radiography (RER) was recently developed for capsule implosions at the National Ignition Facility. RER was demonstrated to image in-flight capsule density gradients such as the fuel-ablator interface that is not visible in traditional absorption only radiography. The latest experiments probing the early time evolution of the implosion allowed the precise measurement of the density gradients. An iterative analysis method has been applied to the RER radiograph to allow the reconstruction of temporal evolution of the radial density distribution from the ice-ablator interface to the ablation front. The estimated density reconstruction precision is <span><math><mrow><mo>±</mo><mn>2</mn><mo>.</mo><mn>4</mn><mtext>%</mtext></mrow></math></span> with a density gradient sensitivity threshold of <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>23</mn></mrow></msup><mspace></mspace><msup><mrow><mi>cm</mi></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span> over a <span><math><mrow><mn>2</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> scale length. This enabled the study of shocks velocity and density gradients as well as ablation front scale length and shape.</div></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"53 ","pages":"Article 101161"},"PeriodicalIF":1.6,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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. Cayzac , G. Boutoux , S. Brygoo , A. Denoeud , S. Depierreux , V. Tassin , F. Albert , E. Alozy , C. Baccou , D. Batani , N. Blanchot , M. Bonneau , M. Bonnefille , R. Botrel , C. Bowen , P. Bradford , M. Brochier , T. Caillaud , A. Chaleil , S. Chardavoine , E. Lefebvre
{"title":"Experimental capabilities of the LMJ-PETAL facility","authors":"W. Cayzac , G. Boutoux , S. Brygoo , A. Denoeud , S. Depierreux , V. Tassin , F. Albert , E. Alozy , C. Baccou , D. Batani , N. Blanchot , M. Bonneau , M. Bonnefille , R. Botrel , C. Bowen , P. Bradford , M. Brochier , T. Caillaud , A. Chaleil , S. Chardavoine , E. Lefebvre","doi":"10.1016/j.hedp.2024.101125","DOIUrl":"https://doi.org/10.1016/j.hedp.2024.101125","url":null,"abstract":"<div><p>Recent progress in the experimental capabilities of the LMJ-PETAL laser facility is reviewed. Updates on the indirect-drive D<sub>2</sub> implosion experiments and equation-of-state experiments using the LMJ laser are presented, including the commissioning of new plasma diagnostics. Several recent campaigns using the PETAL laser alone are also presented, namely the development of a platform using high-resolution and high-energy X-ray sources for radiography experiments, laser wakefield acceleration studies in the self-modulated regime, and neutron generation using a Target Normal Sheath Accelerated proton beam in a pitcher-catcher configuration.</p></div>","PeriodicalId":49267,"journal":{"name":"High Energy Density Physics","volume":"52 ","pages":"Article 101125"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141478611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}