Opacity calculations for laser plasma applications

Conference · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6969911

Magee, Jr, N H

The Los Alamos LTE light element detailed configuration opacity code (LEDCOP) has been revised to provide more accurate absorption coefficients and group means for modern radiation-hydrodynamic codes. The new group means will be especially useful for computing the transport of thermal radiation from laser deposition. The principal improvement is the inclusion of a complete set of accurate and internally consistent LS term energies and oscillator strengths in both the EOS and absorption coefficients. Selected energies and oscillator strengths were calculated from a Hartree-Fock code, then fitted by a quantum defect method. This allowed transitions at all wavelengths to be treated consistently and accurately instead of being limited to wavelength regions covered by experimental observations or isolated theoretical calculations. A second improvement is the use of more accurate photoionization cross sections for excited as well as ground state configurations. These cross sections are now more consistent with the bound-bound oscillator strengths, leading to a smooth transition across the continuum limit. Results will be presented showing the agreement of the LS term energies and oscillator strengths with observed values. The new absorption coefficients will be compared with previous calculations. 5 refs., 9 figs., 1 tab.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6969911
• Report Number(s): LA-UR-86-4153; CONF-861177-4; ON: DE87003728
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700100* -- Fusion Energy-- Plasma Research
ALUMINIUM
COMPUTER CODES
CROSS SECTIONS
ELECTROMAGNETIC RADIATION
ELEMENTS
IONIZATION
LASER RADIATION
METALS
NONMETALS
OPACITY
OPTICAL PROPERTIES
OXYGEN
PHOTOIONIZATION
PHYSICAL PROPERTIES
PLASMA
RADIATIONS