Optically thick plasma

Radiation Transfer in Plasma Optically Thin and Optically Thick Plasmas... 

Laser-driven plasma Optically thick plasma found near a surface heated to the point of vaporization by an intense laser beam the beam ionizes some of the vapor and through the process of avalanche breakdown creates the plasma. 

Observational evidence for the dynamic mass-flow phase includes (A) light-curves where the secondary eclipse becomes deeper at shorter wavelengths (Kondo et al. 1985), (B) the non-monotonic variation of the spectral energy distribution which is pronounced in the ultraviolet (Kondo et al. 1985), and (C) continued presence, both inside and outside the eclipses, of emission features observed in beta Lyrae (Hack et al. 1977). Phenomena (A) and (B) have been attributed to the presence of variable, optically-thick, extrastellar plasma. 

The quasi-equihbrium radiation intensity Ia>AT ) is shown here as a function of temperature and therefore, an indirect function of the optical coordinate. In relation (3-113), Tft, is the optical thickness of plasma referred to a specific ray and specific spectral range. If optical thickness is small (t, 1), it is usually referred to as the transparent... 

It should be noted that some pulse-discharge plasmas with high electron density can be optically thick... 

EXAMPLE 4.2 Sodium is a metal with a density of conduction electrons N = 2.65 X 10 cm f Determine (a) its plasma frequency, (b) the wavelength region of transparency, and (c) the optical density at very low frequencies for a Na sample of 1 mm thickness. 

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