Title :
Time dependent imaging of cylindrical shocks at the Pegasus facility
Author :
King, N.S.P. ; Sorenson, D.S. ; Obst, A.W. ; Gray, N. ; Holmes, V. ; Jaramillo, S. ; Yates, G.J. ; Picklesimer, A. ; Platts, D. ; Stokes, J. ; Hockaday, M.P. ; Coulter, W. ; Oona, H. ; Findley, C. ; Adams, P. ; Guzik, J. ; Lund, C. ; Bowers, R. ; Malone,
Author_Institution :
Phys. Div., Los Alamos Nat. Lab., NM, USA
Abstract :
The pulsed power Pegasus facility at Los Alamos National Laboratory has been configured to drive cylindrically symmetric shocks into a load region containing multiple density regions. A series of experiments are being performed to permit the development of diagnostic techniques to characterize the spatial distribution and temporal dependence of the cylindrical shocks generated in a 4.5 cm diameter/spl times/2 cm thick "target" region. The loads utilized in the preliminary experiments contain multiple regions. Optically transmissive regions are being diagnosed with long pulse, 694 nm laser backlighting. Framing cameras and fast optically shuttered cameras are being developed for high resolution image capture. Pulsed X-ray sources permit characterization of material boundary regions through differential X-ray absorption in a radiographic geometry. The desire for multiple visible and X-ray images requires fast time response, electronic imaging techniques. Typical shock pressures and velocities of 300 Kbar and 5 mm//spl mu/s coupled with a desired spatial resolution of better than 5lp/mm dictate temporal resolution requirements on the order of 50 ns. The current status of the diagnostic development is described as well as possible directions for future improvements.
Keywords :
X-ray imaging; high-speed optical techniques; measurement by laser beam; power supplies to apparatus; pulse generators; pulsed power technology; shock waves; 2 cm; 300 kbar; 4.5 cm; 5000 mm/s; 694 nm; Los Alamos National Laboratory; Pegasus facility; X-ray images; cylindrical shocks; cylindrically symmetric shocks; diagnostic techniques; differential X-ray absorption; fast optically shuttered cameras; framing cameras; high resolution image capture; load region; long pulse laser backlighting; material boundary regions; multiple density regions; multiple visible images; optically transmissive regions; pulsed X-ray sources; pulsed power Pegasus facility; radiographic geometry; shock pressures; shock velocities; spatial distribution; temporal dependence; time dependent imaging; Cameras; Character generation; Electric shock; Image resolution; Laboratories; Optical imaging; Optical pulses; Spatial resolution; X-ray imaging; X-ray lasers;
Conference_Titel :
Pulsed Power Conference, 1995. Digest of Technical Papers., Tenth IEEE International
Conference_Location :
Albuquerque, NM, USA
Print_ISBN :
0-7803-2791-8
DOI :
10.1109/PPC.1995.599746