Observation of a reflected shock in an indirectly driven spherical implosion at the national ignition facility

S Le Pape; L Divol; L Berzak Hopkins; A Mackinnon; N B Meezan; D Casey; J Frenje; H Herrmann; J McNaney; T Ma; K Widmann; A Pak; G Grimm; J Knauer; R Petrasso; A Zylstra; H Rinderknecht; M Rosenberg; M Gatu-Johnson; J D Kilkenny

doi:10.1103/PhysRevLett.112.225002

Observation of a reflected shock in an indirectly driven spherical implosion at the national ignition facility

Phys Rev Lett. 2014 Jun 6;112(22):225002. doi: 10.1103/PhysRevLett.112.225002. Epub 2014 Jun 4.

Authors

S Le Pape¹, L Divol¹, L Berzak Hopkins¹, A Mackinnon¹, N B Meezan¹, D Casey¹, J Frenje², H Herrmann³, J McNaney¹, T Ma¹, K Widmann¹, A Pak¹, G Grimm³, J Knauer⁴, R Petrasso², A Zylstra², H Rinderknecht², M Rosenberg², M Gatu-Johnson², J D Kilkenny⁵

Affiliations

¹ Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
² Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
³ Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
⁴ Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA.
⁵ General Atomics Corporation, La Jolla, California 92121, USA.

PMID: 24949774
DOI: 10.1103/PhysRevLett.112.225002

Abstract

A 200 μm radius hot spot at more than 2 keV temperature, 1 g/cm^{3} density has been achieved on the National Ignition Facility using a near vacuum hohlraum. The implosion exhibits ideal one-dimensional behavior and 99% laser-to-hohlraum coupling. The low opacity of the remaining shell at bang time allows for a measurement of the x-ray emission of the reflected central shock in a deuterium plasma. Comparison with 1D hydrodynamic simulations puts constraints on electron-ion collisions and heat conduction. Results are consistent with classical (Spitzer-Harm) heat flux.