| High energy density physics is the research about the structure or the evolution of the matter under the situation of the energy density higher than1011J/m3, or equivalent to the pressure is1million atmospheres. The subject of laser-plasmas research is also about the substances’behavior in the high energy density. The parameters of the studying subjects covers the number density in range of ne～[1019,1026]cm-3and the temperature covers Te～[0.1eV,10keV], all materials in this regime are the objects to study. And the study about the hot and low-density plasma has been launched for many years and the experimental technic and theory are mature.but we still know little about the behaviors and the evolution of the dense plasmas, in which the electron density researches the liquid or solid even over-solid density. The samples in the warm dense state should be created firstly and the basic parameters of the samples needed to diagnosed. And it is the only way to understand the more dense materials and the stars in universe. And It is the basement to research and understand the evolutionary process of the main fuel layer in ICF and the outer of the stellar and the inner core of the giant planets.The powerful probe, no matter what is the particles or the photons, is needed to penestrate through the dense sample, and record on recording. The hard x-ray photon is feasible to be probe applied in the diagnose experiments about the dense plasma. In this dissertation, the progresses on the x-ray Thomson scattering experiment of warm dense carbon plasma are presented. The scattering happened between the isochoric heated carbon plasma and the x-ray photon. The x-ray probe is emitted from the Titanium foils in the intense laser field, and the structure of the probe is clear and quasi-monoenergetic. And the result shows that the x-ray Thomson scattering is reliable and precise, and the experiment of x-ray Thomson scattering can be launched on the kilo-Joules laser facility.The main achievements presented in the dissertation are:(1) Based on Random Phase Approximation (RPA) model, in which the short-range interaction between the electrons is ignored, the dynamic structure factor (DSF) of the warm dense plasma is deduced and the calculation program for the DSF is developed. And we can accurately obtain the parameters by fitting non-collective Thomson scattering profiles, such as the electron temperature, density and average ionization degree in the plasma.(2) Added the collisions between electron and ion into the RPA model, this model is called as Born-Mermin approximation(BMA) in which collision is treated the interaction between the ion and electron as perturbation and keep the local electron number conversation. The BMA model can provide more precise than RPA model in calculation of the collective motion in the warm dense plasma. And in the non-collective scattering, the results of two model is coincident.(3) designed the crystal spectrometers with different resolution for the x-ray Thomson scattering experiment. The resolution is relatively E/△E=300E/△E=500. For the x-ray photon with4750eV, the resolving power is18eV and10.6eV. and the lower resolving spectrometer is for diagnosis of non-coherence scattering, and the higher one is for the coherence scattering. For the coherence scattering, the energy shift of resonance peak is always above15eV, so it is enough to resolve the scattering signal.(4) The x-ray Thomson scattering has been demonstrated on the SGII laser facility. And warm dense carbon plasma is produced. The size of sample cyclinder is400um diam,600um length, heated by the M-band of Tantalum. The probe light is the He-a lines of the Titanium, and the pulse width of probe is one nanosecond. Using the RPA model program, we get that the electron temperature is33eV and the electron density is1.6*1023cm-3. |
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