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Title: Purgatorio - A new implementation of the Inferno algorithm

Journal Article · · Journal of Quantitative Spectroscopy and Radiative Transmission, vol. 99, no. 1-3, June 1, 2006, pp. 658-679
OSTI ID:936469

For astrophysical applications, as well as modeling laser-produced plasmas, there is a continual need for equation-of-state data over a wide domain of physical conditions. This paper presents algorithmic aspects for computing the Helmholtz free energy of plasma electrons for temperatures spanning from a few Kelvin to several KeV, and densities ranging from essentially isolated ion conditions to such large compressions that most bound orbitals become delocalized. The objective is high precision results in order to compute pressure and other thermodynamic quantities by numerical differentiation. This approach has the advantage that internal thermodynamic self-consistency is ensured, regardless of the specific physical model, but at the cost of very stringent numerical tolerances for each operation. The computational aspects we address in this paper are faced by any model that relies on input from the quantum mechanical spectrum of a spherically symmetric Hamiltonian operator. The particular physical model we employ is that of INFERNO; of a spherically averaged ion embedded in jellium. An overview of PURGATORIO, a new implementation of the INFERNO equation of state model, is presented. The new algorithm emphasizes a novel decimation scheme for automatically resolving the structure of the continuum density of states, circumventing limitations of the pseudo-R matrix algorithm previously utilized.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
936469
Report Number(s):
UCRL-JRNL-211007; TRN: US0805527
Journal Information:
Journal of Quantitative Spectroscopy and Radiative Transmission, vol. 99, no. 1-3, June 1, 2006, pp. 658-679, Vol. 99, Issue 1-3
Country of Publication:
United States
Language:
English