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Author Milovich, J. L. ♦ Robey, H. F. ♦ Clark, D. S. ♦ Baker, K. L. ♦ Casey, D. T. ♦ Cerjan, C. ♦ Field, J. ♦ MacPhee, A. G. ♦ Pak, A. ♦ Patel, P. K. ♦ Peterson, J. L. ♦ Smalyuk, V. A. ♦ Weber, C. R.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PLASMA PHYSICS AND FUSION TECHNOLOGY ♦ ABLATION ♦ COMPRESSION ♦ DENSITY ♦ D-T OPERATION ♦ IMPLOSIONS ♦ INERTIAL CONFINEMENT ♦ LASER RADIATION ♦ NEUTRONS ♦ PLASMA INSTABILITY ♦ PULSES ♦ THERMONUCLEAR FUELS ♦ TWO-DIMENSIONAL CALCULATIONS ♦ US NATIONAL IGNITION FACILITY ♦ YIELDS
Abstract Experimental results from indirectly driven ignition implosions during the National Ignition Campaign (NIC) [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] achieved a record compression of the central deuterium-tritium fuel layer with measured areal densities up to 1.2 g/cm{sup 2}, but with significantly lower total neutron yields (between 1.5 × 10{sup 14} and 5.5 × 10{sup 14}) than predicted, approximately 10% of the 2D simulated yield. An order of magnitude improvement in the neutron yield was subsequently obtained in the “high-foot” experiments [O. A. Hurricane et al., Nature 506, 343 (2014)]. However, this yield was obtained at the expense of fuel compression due to deliberately higher fuel adiabat. In this paper, the design of an adiabat-shaped implosion is presented, in which the laser pulse is tailored to achieve similar resistance to ablation-front instability growth, but with a low fuel adiabat to achieve high compression. Comparison with measured performance shows a factor of 3–10× improvement in the neutron yield (>40% of predicted simulated yield) over similar NIC implosions, while maintaining a reasonable fuel compression of >1 g/cm{sup 2}. Extension of these designs to higher laser power and energy is discussed to further explore the trade-off between increased implosion velocity and the deleterious effects of hydrodynamic instabilities.
ISSN 1070664X
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-12-15
Publisher Place United States
Journal Physics of Plasmas
Volume Number 22
Issue Number 12


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