| Abstrakt: |
Impulse generation by superintense (I ... 10[sup 16] W/cm²) ultrashort-duration (τ ... 100 fs) laser pulses interacting with solid targets in vacuum, and the possible diagnostic utility of impulse or shock pressure measurements in this regime, are examined by means of computations and simple theory. Easily observable impulse levels, up to several hundred dyne s/cm², should be attainable with present lasers. However, the anticipated rapid attenuation of these high-pressure, short-duration shocks in propagating through the target material will pose a significant challenge for target design. When combined with other diagnostic information (e.g., pulse reflectivity, ablation plasma properties, and plasma radiation emission) and a comprehensive modeling capability, we show that impulse or shock pressure data can clarify the laser/target interaction physics, especially regarding the energy absorption efficiency and depth, and the rate energy diffuses into the target during the brief irradiation time. This work was supported by U.S. DOE under contract W-7405-ENG-48 by LLNL. [ABSTRACT FROM AUTHOR] |
