Indications of flow near maximum compression in layered deuterium-tritium implosions at the National Ignition Facility

Gatu Johnson, M.; Knauer, J. P.; Cerjan, C. J.; Eckart, M. J.; Grim, G. P.; Hartouni, E. P.; Hatarik, R.; Kilkenny, J. D.; Munro, D. H.; Sayre, D. B.; Spears, B. K.; Bionta, R. M.; Bond, E. J.; Caggiano, J. A.; Callahan, D.; Casey, D. T.; Doppner, T.; Frenje, J. A.; Glebov, V. Yu.; Hurricane, O.; Kritcher, A.; LePape, S.; Ma, T.; Mackinnon, A.; Meezan, N.; Patel, P.; Petrasso, R. D.; Ralph, J. E.; Springer, P. T.; Yeamans, C. B.

doi:10.1103/PhysRevE.94.021202

Title: Indications of flow near maximum compression in layered deuterium-tritium implosions at the National Ignition Facility

Journal Article · 15 August 2016 · Physical Review E

DOI: https://doi.org/10.1103/PhysRevE.94.021202 · OSTI ID:1313547

Gatu Johnson, M. ^[1]; Knauer, J. P. ^[2]; Cerjan, C. J. ^[3]; Eckart, M. J. ^[3]; Grim, G. P. ^[3]; Hartouni, E. P. ^[3]; Hatarik, R. ^[3]; Kilkenny, J. D. ^[4]; Munro, D. H. ^[3]; Sayre, D. B. ^[3]; Spears, B. K. ^[3]; Bionta, R. M. ^[3]; Bond, E. J. ^[3]; Caggiano, J. A. ^[3]; Callahan, D. ^[3]; Casey, D. T. ^[3]; Doppner, T. ^[3]; Frenje, J. A. ^[1]; Glebov, V. Yu. ^[2]; Hurricane, O. ^[3] more »

Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Univ. of Rochester, Rochester, NY (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
General Atomics, San Diego, CA (United States)

Here, an accurate understanding of burn dynamics in implosions of cryogenically layered deuterium (D) and tritium (T) filled capsules, obtained partly through precision diagnosis of these experiments, is essential for assessing the impediments to achieving ignition at the National Ignition Facility. We present measurements of neutrons from such implosions. The apparent ion temperatures T_ion are inferred from the variance of the primary neutron spectrum. Consistently higher DT than DD T_ion are observed and the difference is seen to increase with increasing apparent DT T_ion. The line-of-sight rms variations of both DD and DT T_ion are small, ~150eV, indicating an isotropic source. The DD neutron yields are consistently high relative to the DT neutron yields given the observed T_ion. Spatial and temporal variations of the DT temperature and density, DD-DT differential attenuation in the surrounding DT fuel, and fluid motion variations contribute to a DT Tion greater than the DD T_ion, but are in a one-dimensional model insufficient to explain the data. We hypothesize that in a three-dimensional interpretation, these effects combined could explain the results.

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Research Organization:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA)

Grant/Contract Number:: AC52-07NA27344; NA0001857; NA0002949

OSTI ID:: 1313547

Alternate ID(s):: OSTI ID: 1294718; OSTI ID: 1324684

Report Number(s):: LLNL-JRNL-682118; PLEEE8

Journal Information:: Physical Review E, Vol. 94, Issue 2; ISSN 2470-0045

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 49 works

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