Accession Number : ADP007058

Title :   Radiation Cooling in Photopumped C VI Inversion,

Corporate Author : LEHIGH UNIV BETHLEHEM PA DEPT OF PHYSICS

Personal Author(s) : Pakula, Ricardo A.

Report Date : 22 MAY 1992

Pagination or Media Count : 5

Abstract : Radiation cooling as a means to reach inversion in photoionized C VI is analyzed in the context of energy transfer between excited ions and free electrons. The application of this scheme for the specific case of a hydrogen-like C VI plasma, exposed to the soft x-ray emissions of a titanium-laser-produced plasma was considered. Necessary conditions for the achievement of inversion are a low plasma temperature (approx. 10 eV), and a high electron density (approx. 10 to the 19th)/cu. cm). Both are required for the establishment of a strong collisional-recombination regime, favouring the cascading of electrons towards the upper excited levels, leaving the lower levels almost unpopulated. Radiative cooling was originally proposed as a means to reach the desired temperature in similar recombination schemes, however posterior work has shown that his regime was not attainable for low-Z materials. In this paper we consider in detail the hypothesis of radiative cooling for the case of C VI pumped by the Ti-plasma.

Descriptors :   *PLASMAS(PHYSICS), *COHERENT OPTICAL RADIATION, *IONIZING RADIATION, SOFT X RAYS, IONIZATION, TITANIUM, ELECTRON DENSITY, SHORT WAVELENGTHS, COHERENT RADIATION, SYMPOSIA.

Subject Categories : Plasma Physics and Magnetohydrodynamics
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE