Radiochemistry diagnostics for the National Ignition Facility

Conference · Mon Feb 22 04:00:00 EST 2010

OSTI ID:976936

Hoffman, R D; Cerjan, C J; Shaughnessy, D A; Moody, K J; Nelson, S L; Bernstein, L A; Stoyer, M A; Fortner, R J; Schneider, D H

Radiochemistry-based techniques will be an important complement to x-ray implosion diagnostics. Simulations demonstrate the value of alpha-induced or deuteron-induced reactions as a direct measurement of static mix contamination in DT-filled ignition capsules. In this proceedings we examine to what extent neutron-induced reactions might be highly correlated with the energetically down-scattered neutron fraction which is, in turn, related to the critical quantity of fuel areal density, {rho}R. Although alpha and deuteron reactions are highly suppressed in HT/D-filled capsules, neutron-induced reactions produce robust abundances and 2% measurements of the relevant radiological ratios is achievable. We conclude that radiochemical data are strongly correlated with the down-scattered fraction and fuel areal density. Unknown physics, primarily uncertainties in the direct T-T fusion neutron cross section and, to a lesser extent, various radiochemical production cross sections are important but calibration shots can be used to reduce these errors. The primary advantage of radiochemistry remains - it is the only technique that samples down-scattered neutrons from the entire capsule during the burn. In particular radiochemistry correlated with other diagnostics can be used to minimize experimental uncertainties and thus maximize gain.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 976936
• Report Number(s): LLNL-PROC-426088
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
42 ENGINEERING
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CALIBRATION
CONTAMINATION
CROSS SECTIONS
DESIGN
DEUTERON REACTIONS
IGNITION
IMPLOSIONS
NEUTRONS
NUCLEAR EXPLOSIVES
PHYSICS
PRODUCTION
RADIOCHEMISTRY
US NATIONAL IGNITION FACILITY