ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
We report results from two separate experiments fielded on the AWE Helen laser facility both diagnosed by interferometry. In the first experiment, measurements were made on preheat in flat targets indirectly driven by 1.8 and 2.2 mm (length and diameter) hohlraums heated by two 0.53 μm, 3 ns duration shaped laser pulses, each of 400 J. The rear surface of the target acts as one mirror of a Michelson interferometer, and the fringe pattern produced is temporally resolved using an optical streak camera. Motion of the fringes prior to the arrival of the shock at the rear surface enables expansion due to preheating to be measured. In the second experiment spallation measurements were made on pure Al. Cylindrical targets (800 μm diameter×500 μm long) were directly driven with one beam of 0.53 μm. 200 ps duration laser pulses of 3–15 J. A time resolved Michelson interferometer recorded the motion of the free surface. Pull back, elastic precursor, and spallation signatures were observed and strain rates of 3×106 s−1 and spall strengths of 33 kbar were measured. © 2001 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1326013
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