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Plasmon resonance in warm dense matter.
R Thiele1, T Bornath, C Fortmann
1Institut für Physik, Universität Rostock, D-18051 Rostock, Germany. robert.thiele@uni-rostock.de
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 15, 2008
Summary
Collective Thomson scattering provides a robust method for measuring free electron density in dense plasmas. Including collisions in the analysis is crucial for accuracy in the transition region of scattering.
Area of Science:
- Plasma physics
- Scattering diagnostics
Background:
- Dense plasmas require accurate free electron density measurements.
- Collective Thomson scattering is a key diagnostic technique.
Purpose of the Study:
- To demonstrate robust free electron density measurement using collective Thomson scattering.
- To investigate the applicability of dispersion relations and the impact of collisions.
Main Methods:
- Utilizing extreme ultraviolet or X-ray light for collective Thomson scattering.
- Comparing standard and improved dispersion relations with dielectric function calculations.
- Generalizing Thomson scattering treatment using the Born-Mermin approximation to include collisions.
Main Results:
- Collective excitations (plasmons) appear as signal maxima, directly relating to electron density.
- The range of applicability for dispersion relations was investigated.
- Collisions were found to be important in the transition region from collective to noncollective scattering.
Conclusions:
- Collective Thomson scattering is a reliable method for determining free electron density in dense plasmas.
- The inclusion of collisions in scattering models is essential for accurate diagnostics, particularly in mixed scattering regimes.
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