K-edge Absorption spectra in Warm Dense Matter

Journal Article · Thu Sep 10 04:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3241191· OSTI ID:21344614

Peyrusse, O; Dorchies, F; Harmand, M; Levy, A ^[1]; Mazevet, S; Recoules, V; Renaudin, P ^[2]; Fuchs, J; Mancic, A; Nakatsutsumi, M; Audebert, P ^[3]

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1. CELIA, UMR 5107, Universite Bordeaux 1-CEA-CNRS, 351 Cours de la Liberation, Talence (France)
2. CEA, DAM, DIF, F-91297, Arpajon (France)
3. LULI, UMR 7605, Ecole Polytechnique, 91128 Palaiseau (France)

The recent development of compact, short (ps or sub-ps) X-ray sources gives access to the structural nature of short time-scale phenomena and to the study of very transient systems such as warm dense materials. Among the structural tools used for the study of static (solid) materials, X-ray Absorption Fine Structure (XAFS) spectroscopy has proven to provide useful information on the local structure (atomic arrangement) and on the electronic Density of States. In a context where the matter is disordered but highly correlated, we present K-edge absorption studies of warm, dense aluminum. The range of temperature starts from the solid and extend to the strongly correlated plasma regime. We describe here two theoretical approaches for the the calculation of the K-edge absorption features. The first one involves a (Modified) HyperNetted Chain--Neutral Pseudo Atom (MHNC-NPA) model of dense matter coupled with a specific model of the XAFS features. The second one is based on ab initio Quantum Molecular Dynamics (QMD) simulations from which a Kubo-Greenwood formulation combined with the Projector Augmented Wave (PAW) formalism gives a direct access to the X-ray absorption spectra. These spectra are compared with recent K-edge absorption measurements in aluminum targets isochorically heated by laser-created protons and probed by a short X-ray backlighting source.

• OSTI ID: 21344614
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1161; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION SPECTRA
ABSORPTION SPECTROSCOPY
ALUMINIUM
ATOMS
BARYONS
CALCULATION METHODS
ELECTRON GAS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY-LEVEL DENSITY
FERMIONS
FINE STRUCTURE
FINITE DIFFERENCE METHOD
HADRONS
ITERATIVE METHODS
LASER TARGETS
LASER-PRODUCED PLASMA
MATHEMATICAL SOLUTIONS
METALS
MOLECULAR DYNAMICS METHOD
NUCLEONS
NUMERICAL SOLUTION
PLASMA
PROTONS
RADIATION SOURCES
SOLIDS
SPECTRA
SPECTROSCOPY
TARGETS
TRANSIENTS
X-RAY SOURCES
X-RAY SPECTRA
X-RAY SPECTROSCOPY