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Quantum and optics effects in dense plasmas with medium temperatures with implications to stellar plasmas

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 Added by Y. Ben-Aryeh
 Publication date 2018
  fields Physics
and research's language is English
 Authors Y. Ben-Aryeh




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The optical properties of plasmas with high densities and medium temperatures are analyzed by the use of a free electron model with Fermi-Dirac statistics. For the present collisional plasma the frequency of electron-ion collision is very large relative to the optical and infra-red frequencies. A quantum mechanical equation for the frequency of collisions is developed by the use of Fermi-Dirac statistics and Rutherford scattering theory. The validity of the Rutherford scattering theory is discussed. The influence of many weak collisions is taken into account by a Coulomb logarithmic function. The present analysis might have implication to stellar plasmas with medium temperatures for which Fermi-Dirac statistics is used. The relations between the present analysis and the stabilities of stars plasmas are discussed. The ratio between the radius and mass of star plasmas with the present densities and that of a typical white dwarf are discussed.

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Fermi Dirac free electron model is applied to very dense plasmas with medium or low temperatures. While Boltzmann statistics can lead to very high densities of ionized electrons, only at very high temperatures, Fermi Dirac statistics can support the high densities of ionized electrons at medium or low temperatures due to the high degeneracies obtained in this model. Since very dense plasmas may be obtained at low temperatures the corresponding black body radiation with the plasma luminosity will be quite small. On the other hand gravitational effects might be quite large due to the high densities. The optical properties for dense plasmas are calculated. The present study might have implications to dense stars plasma.
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