Experimental measurement of Au M-band flux in indirectly-driven double-shell implosions

Journal Article · Fri Sep 17 04:00:00 EDT 2004 · Physics of Plasmas

OSTI ID:875671

Robey, H F; Perry, T S; Park, H S; Amendt, P; Sorce, C M; Compton, S M; Campbell, K M; Knauer, J P

Indirectly-driven double-shell implosions are being investigated as a possible noncryogenic path to ignition on the National Ignition Facility (NIF). In recent double-shell implosions, the inner shell trajectory was shown to exhibit a strong sensitivity to the temporal history of the M-band (2-5 keV) radiation emitted from the Au hohlraum wall. A large time-dependent discrepancy was observed between measurement and simulation of the x-ray flux in this range. In order to better characterize the radiation environment seen in these implosions, an experimental campaign was conducted on the Omega Laser. A number of diagnostics were used to measure both the temporal and spectral nature of the M-band flux. Results were obtained from an absolutely calibrated 12 channel filtered x-ray diode array (Dante) as well as two streaked crystal spectrometers and an absolutely calibrated time-integrated spectrometer (Henway). X-ray backlighting was also used to directly measure the effect of M-band radiation on the trajectory of the inner shell. The data from all diagnostics are shown to be in excellent agreement and provide a consistent picture of the M-band flux. These results are being used to improve the simulation of hohlraum-generated M-band radiation that will be necessary for the design of future double-shell implosions employing higher Z inner shells.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 875671
• Report Number(s): UCRL-JRNL-207771
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Vol. 12; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DESIGN
IGNITION
IMPLOSIONS
RADIATIONS
SENSITIVITY
SIMULATION
SPECTROMETERS
US NATIONAL IGNITION FACILITY