Full Coulomb calculation of Stark broadened spectra from multielectron ions: A focus on the dense plasma line shift

Junkel, Gwyneth; Gunderson, Michael A.; Hooper, C. F.; Haynes, D. A.

doi:10.1103/physreve.62.5584

Cited by 40 publications

(33 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rather than treating the exchange term of the Hartree-Fock equations as an inhomogeneous term of the differential equation, we treat it explicitly as an integro-differential equation. We have written the exchange integral as a matrix and then, by approximating the rest of the Hamiltonian terms as finite-difference coefficients, we can use linear algebra packages such as 5 This method of using an exact exchange treatment is now being implemented in the DWE line shape code [9,43] (which was used in the SLSP4 workshop [44]), which improves upon the relaxation theory method of Junkel et al [14] to include exchange. 6 This may be a dangerous approximation because some (non-negligible) processes need to be considered when orthogonality is not guaranteed.…”

Section: Discussionmentioning

confidence: 99%

“…The integral in Equation (14) can be discretized as follows (where r 1 have been replaced with a spatial index, x∆r),…”

Section: Matrix Form Of the Hartree-fock Equationmentioning

confidence: 99%

“…Second, many calculations approximate plasma particles as classical, even if they use a more accurate radiator-plasma interaction [10][11][12]. Lastly, many calculations are performed in a high-temperature regime where exchange effects are assumed to be negligible [13,14].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

Gomez

Nagayama

Fontes

et al. 2018

Atoms

View full text Add to dashboard Cite

Atomic structure of N-electron atoms is often determined by solving the Hartree-Fock equations, which are a set of integro-differential equations. The integral part of the Hartree-Fock equations treats electron exchange, but the Hartree-Fock equations are not often treated as an integro-differential equation. The exchange term is often approximated as an inhomogeneous or an effective potential so that the Hartree-Fock equations become a set of ordinary differential equations (which can be solved using the usual shooting methods). Because the Hartree-Fock equations are an iterative-refinement method, the inhomogeneous term relies on the previous guess of the wavefunction. In addition, there are numerical complications associated with solving inhomogeneous differential equations. This work uses matrix methods to solve the Hartree-Fock equations as an integro-differential equation. It is well known that a derivative operator can be expressed as a matrix made of finite-difference coefficients; energy eigenvalues and eigenvectors can be obtained by using linear-algebra packages. The integral (exchange) part of the Hartree-Fock equation can be approximated as a sum and written as a matrix. The Hartree-Fock equations can be solved as a matrix that is the sum of the differential and integral matrices. We compare calculations using this method against experiment and standard atomic structure calculations. This matrix method can also be used to solve for free-electron wavefunctions, thus improving how the atoms and free electrons interact. This technique is important for spectral line broadening in two ways: it improves the atomic structure calculations, and it improves the motion of the plasma electrons that collide with the atom.

show abstract

Section: Discussionmentioning

confidence: 99%

“…The integral in Equation (14) can be discretized as follows (where r 1 have been replaced with a spatial index, x∆r),…”

Section: Matrix Form Of the Hartree-fock Equationmentioning

confidence: 99%

See 1 more Smart Citation

Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

Gomez

Nagayama

Fontes

et al. 2018

Atoms

View full text Add to dashboard Cite

show abstract

“…According to theoretical predictions [3][4][5][6], the widths and frequency shifts of Stark-broadened lines are strongly density dependent and relatively weakly temperature dependent. Consequently, the line widths of hydrogenic ions are standardly used for density diagnosis of laboratory plasmas.…”

Section: Introductionmentioning

confidence: 96%

Spectroscopic characterization of plasma densities of laser-irradiated Al foils

Renner¹,

Limpouch²,

Krouský³

et al. 2003

Journal of Quantitative Spectroscopy and Radiative Transfer

View full text Add to dashboard Cite

Detailed spectroscopic analysis of K-shell emission simultaneously observed at the irradiated and unirradiated surface of laser-exploded foils is reported. The space-dependent spectral line widths and relative shifts in the positions of the Al Lyman transition are interpreted in terms of the plasma density variations; the trend in the shifts data supports the idea of a density-dependent line shift. The signiÿcant features of the spectra emitted from the densest part of the plasma are compared with predictions from standard diagnostics modeling based on codes MEDUSA and FLY, and with the results of 2D ATLANT hydrodynamic simulations post-processed with a novel suite of atomic physics codes XEPAP. The results obtained corroborate the feasibility of the plasma density diagnostics based on line shifts in the intermediately coupled plasmas. ?

show abstract

“…However, further investigation into this issue is required to understand how other models of continuum-lowering can be applied to multi-component plasmas so that their predictions for edge shifts could be implemented into a spectral synthesis model. In this regard, dense plasma line shifts [23][24][25] should be included as well. Work is in progress to address these issues, including the impact of the overlap of the Lyj3 line emission with bound-free emission on temperature determination in implosion core plasmas.…”

Section: Photon Energy (Ev)mentioning

confidence: 99%

Argon K-shell and bound-free emission from OMEGA direct-drive implosion cores

Florido

Mancini

Nagayama

et al. 2010

High Energy Density Physics

View full text Add to dashboard Cite

We discuss calculations of synthetic spectra for the interpretation and analysis of K-shell and bound-free emission from argon-doped deuterium-filled OMEGA direct-drive implosion cores. The spectra are computed using a model that considers collisional-radiative atomic kinetics, continuum-lowering, detailed Stark-broadened line shapes, line overlapping, and radiation transport effects. The photon energy range covers the moderately optically thick n = 3 -• n = 1 and n = 4 -• n = 1 line transitions in He-and H-like Ar, their associated satellite lines in Li-and He-like Ar, and several radiative recombination edges. At the high-densities characteristic of implosion cores, the radiative recombination edges substantially shift to lower energies thus overlapping with several line transitions. We discuss the application of the spectra to spectroscopic analysis of doped implosion cores.

show abstract

Full Coulomb calculation of Stark broadened spectra from multielectron ions: A focus on the dense plasma line shift

Cited by 40 publications

References 34 publications

Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

Matrix Methods for Solving Hartree-Fock Equations in Atomic Structure Calculations and Line Broadening

Spectroscopic characterization of plasma densities of laser-irradiated Al foils

Argon K-shell and bound-free emission from OMEGA direct-drive implosion cores

Contact Info

Product

Resources

About