Performance of indirectly driven capsule implosions on NIF using adiabat-shaping

9th International Conference on Inertial Fusion Sciences and Applications

Robey, H.F.^1 ; Smalyuk, V.A.^1 ; Milovich, J.L.^1 ; Döppner, T.^1 ; Casey, D.T.^1 ; Baker, K.L.^1 ; Peterson, J.L.^1 ; Bachmann, B.^1 ; Hopkins, L F Berzak^1 ; Bond, E.^1 ; Caggiano, J.A.^1 ; Callahan, D.A.^1 ; Celliers, P.M.^1 ; Cerjan, C.^1 ; Clark, D.S.^1 ; Dixit, S.N.^1 ; Edwards, M.J.^1 ; Gharibyan, N.^1 ; Haan, S.W.^1 ; Hammel, B.A.^1 ; Hamza, A.V.^1 ; Hatarik, R.^1 ; Hurricane, O.A.^1 ; Jancaitis, K.S.^1 ; Jones, O.S.^1 ; Kerbel, G.D.^1 ; Kroll, J.J.^1 ; Lafortune, K.N.^1 ; Landen, O.L.^1 ; Ma, T.^1 ; Marinak, M.M.^1 ; Macgowan, B.J.^1 ; Macphee, A.G.^1 ; Pak, A.^1 ; Patel, M.^1 ; Patel, P.K.^1 ; Perkins, L.J.^1 ; Sayre, D.B.^1 ; Sepke, S.M.^1 ; Spears, B.K.^1 ; Tommasini, R.^1 ; Weber, C.R.^1 ; Widmayer, C.C.^1 ; Yeamans, C.^1 ; Giraldez, E.^2 ; Hoover, D.^2 ; Nikroo, A.^1 ; Hohenberger, M.^3 ; Johnson, M Gatu^4

Lawrence Livermore National Laboratory, Livermore

CA

94551, United States^1

General Atomics, San Diego

CA

92186, United States^2

Laboratory for Laser Energetics, Rochester

NY

14623, United States^3

Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge

MA

02139, United States^4

关键词: Ablation fronts;    Higher yield;    Instability growth;    National ignition facility;    Neutron yields;    NO reduction;    Relative contribution;    Space between;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/717/1/012045/pdf
DOI  :  10.1088/1742-6596/717/1/012045

来源: IOP

【 摘 要 】

A series of indirectly driven capsule implosions has been performed on the National Ignition Facility to assess the relative contributions of ablation-front instability growth vs. fuel compression on implosion performance. Laser pulse shapes for both low and high-foot pulses were modified to vary ablation-front growth & fuel adiabat, separately and controllably. Two principal conclusions are drawn from this study: 1) It is shown that an increase in laser picket energy reduces ablation-front instability growth in low-foot implosions resulting in a substantial (3-10X) increase in neutron yield with no loss of fuel compression. 2.) It is shown that a decrease in laser trough power reduces the fuel adiabat in high-foot implosions results in a significant (36%) increase in fuel compression together with no reduction in neutron yield. These results taken collectively bridge the space between the higher compression low-foot results and the higher yield high-foot results.