49th Annual Meeting of the Division of Plasma Physics
Volume 52, Number 11
Monday–Friday, November 12–16, 2007;
Orlando, Florida
Session GI1: Direct Drive Inertial Confinement Fusion and Z Pinches
9:30 AM–12:30 PM,
Tuesday, November 13, 2007
Rosen Centre Hotel
Room: Junior Ballroom
Chair: Craig Sangster, University of Rochester, Laboratory for Laser Energetics
Abstract ID: BAPS.2007.DPP.GI1.2
Abstract: GI1.00002 : OMEGA Experiments on the Shock-Ignition ICF Concept
10:00 AM–10:30 AM
Preview Abstract
Abstract
Author:
W. Theobald
(Laboratory for Laser Energetics, U. of Rochester)
Shock ignition\footnote{ R. Betti \textit{et al}., Phys. Rev. Lett. \textbf{98}, 155001
(2007).} is an ICF concept that assembles thermonuclear fuel to high areal
densities and then ignites it by launching a strong shock wave into the
compressed fuel. The low-adiabat fuel assembly implodes with a velocity that
is less than that required for hot-spot ignition. An intensity spike at the
end of the main drive pulse generates a strong shock that is timed to meet
the return shock bouncing back from the capsule center in the hot spot. The
resulting fuel assembly is non-isobaric and will ignite with less energy
than a conventional isobaric implosion.$^{1}$ Experiments to study the
shock-ignition concept were performed on the OMEGA Laser System using
40-\textit{$\mu $}m-thick, 0.9-mm-diam plastic shells filled with D$_{2}$ gas. The targets
were driven by a relaxation adiabat-shaping laser pulse with a short picket
pulse\footnote{ K. Anderson and R. Betti, Phys. Plasmas \textbf{11}, 5
(2004).} and a high-intensity spike. The implosion was optimized by
measuring the fuel assembly performance as a function of the timing of the
picket pulse and the spike. Neutron-averaged areal densities of $\sim $200
mg/cm$^{2}$ were measured. The shock-generated implosion showed fusion
product yields enhanced by a factor of $\sim $4 compared to an implosion
without the spike. The measured neutron yield for a 25-atm fill, an adiabat
of 1.6, and 17 kJ of laser energy was $\sim $10{\%} of the 1-D simulation
prediction. This work was supported by the U.S. Department of Energy Office
of Inertial Confinement Fusion under Cooperative Agreements
DE-FC52-92SF19460 and DE-FC02-04ER54789. Contributors: R. Betti,$^{\ast }$
C. Stoeckl, K.S. Anderson,$^{\ast }$ J.A. Delettrez, V.Yu. Glebov, F.J.
Marshall, D.N. Maywar, R.L. McCrory, D.D. Meyerhofer, P.B. Radha, T.C.
Sangster, V.A. Smalyuk, A.A. Solodov,$^{\ast }$ B. Yaakobi, and C.D. Zhou,
\textit{UR/LLE}; J.A. Frenje, C.K. Li, R.D. Petrasso, and F.H. S\'{e}guin, \textit{MIT-PSFC}; L.J. Perkins,
\textit{LLNL}; D. Shvarts, \textit{NRCN (Israel)}. $^{\ast }$Also at the Fusion Science Center for Extreme
States of Matter and Fast Ignition.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.DPP.GI1.2