X-ray Streak Camera Cathode Development and Timing Accuracy of the 4w UV Fiducial System at the National Ignition Facility

Conference · Wed May 02 04:00:00 EDT 2012

OSTI ID:1044234

Opachich, Y P; Palmer, N; Homoelle, D; Hatch, B W; Bell, P; Bradley, D; Kalantar, D; Browning, D; Landen, O

The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a {+-}2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4-{omega} (263nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, Titanium, Gold and Silver photocathode materials have been tested. Aluminum showed the highest quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data was analyzed to determine the centroiding a statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of {+-}1.6 ps and {+-}0.7 ps respectively.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 1044234
• Report Number(s): LLNL-CONF-556394
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCURACY
ALUMINIUM
CATHODES
GOLD
LASERS
PHOTOCATHODES
PLASMA DIAGNOSTICS
QUANTUM EFFICIENCY
SILVER
STREAK CAMERAS
TITANIUM
US NATIONAL IGNITION FACILITY
VELOCITY
X-RAY SOURCES