Systematic investigation of NLTE phenomena in the limit of small departures from LTE

Journal Article · Tue Apr 15 04:00:00 EDT 1997 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.53537· OSTI ID:21167509

Libby, S B; Graziani, F R; More, R M; Kato, T ^[1]

---

1. Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)

In this paper, we begin a systematic study of Non-Local Thermal Equilibrium (NLTE) phenomena in near equilibrium (LTE) high energy density, highly radiative plasmas. It is shown that the principle of minimum entropy production rate characterizes NLTE steady states for average atom rate equations in the case of small departures form LTE. With the aid of a novel hohlraum-reaction box thought experiment, we use the principles of minimum entropy production and detailed balance to derive Onsager reciprocity relations for the NLTE responses of a near equilibrium sample to non-Planckian perturbations in different frequency groups. This result is a significant symmetry constraint on the linear corrections to Kirchoff's law. We envisage applying our strategy to a number of test problems which include: the NLTE corrections to the ionization state of an ion located near the edge of an otherwise LTE medium; the effect of a monochromatic radiation field perturbation on an LTE medium; the deviation of Rydberg state populations from LTE in recombining or ionizing plasmas; multi-electron temperature models such as that of Busquet; and finally, the effect of NLTE population shifts on opacity models.

• OSTI ID: 21167509
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 406; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ATOMS
CORRECTIONS
DISTURBANCES
ELECTRON TEMPERATURE
ENERGY DENSITY
ENTROPY
IONIZATION
IONS
LTE
MONOCHROMATIC RADIATION
OPACITY
PLASMA
RYDBERG STATES
SYMMETRY