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Updated: Jun 1, 2026
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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Time evolution of collisionless shock in counterstreaming laser-produced plasmas
Y Kuramitsu1, Y Sakawa, T Morita
1Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka, 565-0871 Japan. kuramitsu-y@ile.osaka-u.ac.jp
Physical Review Letters
|June 4, 2011
Summary
We observed the formation of a strong collisionless shock in counterstreaming plasmas created by a high-power laser. The shock was remarkably thin, thinner than the ion mean free path, indicating high Mach numbers.
Area of Science:
- Plasma physics
- High-energy-density physics
- Astrophysical shock waves
Background:
- Collisionless shocks are crucial in astrophysical phenomena.
- Understanding shock formation in laboratory plasmas provides insights into space environments.
- High-power lasers enable the creation of extreme plasma conditions.
Purpose of the Study:
- To investigate the time evolution and characteristics of a strong collisionless shock.
- To analyze shock formation in laser-driven counterstreaming plasmas.
- To determine the shock thickness and Mach numbers in this experimental setup.
Main Methods:
- Generating counterstreaming plasmas by irradiating a CH double-plane target with a high-power laser pulse.
- Utilizing self-emission streaked optical pyrometry to observe shock formation.
- Employing two-dimensional snapshots of self-emission and shadowgrams for structural analysis.
Main Results:
- Observed steepening of the self-emission profile, indicating shock formation.
- Determined that the shock thickness is less than the mean free path of counterstreaming ions.
- Estimated very high Mach numbers based on flow velocity and brightness temperatures.
Conclusions:
- Confirmed the formation of a strong collisionless shock in laser-produced counterstreaming plasmas.
- Demonstrated the existence of extremely thin shock structures in this regime.
- The findings suggest high-energy-density conditions and significant shock strengths were achieved.
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