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Title: Radiation Transfer Effects on the Spectra of Laser-Generated Plasmas

Abstract

Experimental x-ray spectra of the H-like 2p{yields}1s (Lyman-{alpha}) doublet have been obtained using time-integrated high-resolution spectroscopy of a constrained-flow, laser-generated aluminum plasma. These spectra show monotonic alteration of the relative intensities of the doublet components with distance from the target surface. Excellent agreement between experiment and theory is found only if the modeling includes both ion collisional rates between the fine-structure components of the n=2 level and, more importantly, the radiative pumping of one Lyman-{alpha} component by the other component along the direction of the major velocity gradient (i.e., perpendicular to the direction of spectra observation). Understanding radiation transfer in plasmas with high velocity gradients is important in modeling many astrophysical objects, and this experiment acts as a benchmark for such complex calculations.

Authors:
; ; ; ; ; ; ; ;  [1];  [2];  [3]
  1. Institute of Physics, Czech Academy of Sciences, 18211 Prague (Czech Republic)
  2. (United Kingdom)
  3. (United States)
Publication Date:
OSTI Identifier:
20777224
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevLett.96.185002; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALUMINIUM; BENCHMARKS; FINE STRUCTURE; LASERS; PLASMA; PLASMA DIAGNOSTICS; RADIANT HEAT TRANSFER; RESOLUTION; SIMULATION; SPECTROSCOPY; VELOCITY; X-RAY SPECTRA

Citation Formats

Renner, O., Kerr, F.M., Wolfrum, E., Hawreliak, J., Chambers, D., Rose, S.J., Wark, J.S., Scott, H.A., Patel, P., Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, and Lawrence Livermore National Laboratory, Livermore, California 94550. Radiation Transfer Effects on the Spectra of Laser-Generated Plasmas. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.185002.
Renner, O., Kerr, F.M., Wolfrum, E., Hawreliak, J., Chambers, D., Rose, S.J., Wark, J.S., Scott, H.A., Patel, P., Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, & Lawrence Livermore National Laboratory, Livermore, California 94550. Radiation Transfer Effects on the Spectra of Laser-Generated Plasmas. United States. doi:10.1103/PhysRevLett.96.185002.
Renner, O., Kerr, F.M., Wolfrum, E., Hawreliak, J., Chambers, D., Rose, S.J., Wark, J.S., Scott, H.A., Patel, P., Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, and Lawrence Livermore National Laboratory, Livermore, California 94550. Fri . "Radiation Transfer Effects on the Spectra of Laser-Generated Plasmas". United States. doi:10.1103/PhysRevLett.96.185002.
@article{osti_20777224,
title = {Radiation Transfer Effects on the Spectra of Laser-Generated Plasmas},
author = {Renner, O. and Kerr, F.M. and Wolfrum, E. and Hawreliak, J. and Chambers, D. and Rose, S.J. and Wark, J.S. and Scott, H.A. and Patel, P. and Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU and Lawrence Livermore National Laboratory, Livermore, California 94550},
abstractNote = {Experimental x-ray spectra of the H-like 2p{yields}1s (Lyman-{alpha}) doublet have been obtained using time-integrated high-resolution spectroscopy of a constrained-flow, laser-generated aluminum plasma. These spectra show monotonic alteration of the relative intensities of the doublet components with distance from the target surface. Excellent agreement between experiment and theory is found only if the modeling includes both ion collisional rates between the fine-structure components of the n=2 level and, more importantly, the radiative pumping of one Lyman-{alpha} component by the other component along the direction of the major velocity gradient (i.e., perpendicular to the direction of spectra observation). Understanding radiation transfer in plasmas with high velocity gradients is important in modeling many astrophysical objects, and this experiment acts as a benchmark for such complex calculations.},
doi = {10.1103/PhysRevLett.96.185002},
journal = {Physical Review Letters},
number = 18,
volume = 96,
place = {United States},
year = {Fri May 12 00:00:00 EDT 2006},
month = {Fri May 12 00:00:00 EDT 2006}
}
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