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Title: The importance of EBIT data for Z-pinch plasma diagnostics

Abstract

The results from the last six years of x-ray spectroscopy and spectropolarimetry of high energy density Z-pinch plasmas complemented by experiments with the electron beam ion trap (EBIT) at the Lawrence Livermore National Laboratory (LLNL) are presented. The two topics discussed are the development of M-shell x-ray W spectroscopic diagnostics and K-shell Ti spectropolarimetry of Z-pinch plasmas. The main focus is on radiation from a specific load configuration called an 'X-pinch'. X-pinches are excellent sources for testing new spectral diagnostics and for atomic modelling because of the high density and temperature of the pinch plasmas, which scale from a few {micro}m to several mm in size. They offer a variety of load configurations, which differ in wire connections, number of wires, and wire materials. In this work the study of X-pinches with tungsten wires combined with wires from other, lower-Z materials is reported. Utilizing data produced with the LLNL EBIT at different energies of the electron beam the theoretical prediction of line positions and intensity of M-shell W spectra were tested and calibrated. Polarization-sensitive X-pinch experiments at the University of Nevada, Reno (UNR) provide experimental evidence for the existence of strong electron beams in Ti and Mo X-pinch plasmas andmore » motivate the development of x-ray spectropolarimetry of Z-pinch plasmas. This diagnostic is based on the measurement of spectra recorded simultaneously by two spectrometers with different sensitivity to the linear polarization of the observed lines and compared with theoretical models of polarization-dependent spectra. Polarization-dependent K-shell spectra from Ti X-pinches are presented and compared with model calculations and with spectra generated by a quasi-Maxwellian electron beam at the LLNL EBIT-II electron beam ion trap.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
972838
Report Number(s):
UCRL-JRNL-229819
Journal ID: ISSN 0008-4204; CJPHAD; TRN: US1001550
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Canadian Journal of Physics, vol. 86, no. 1, January 1, 2008, pp. 267-276; Journal Volume: 86; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 70 PLASMA PHYSICS AND FUSION; CONFIGURATION; ELECTRON BEAMS; ENERGY DENSITY; FORECASTING; K SHELL; LAWRENCE LIVERMORE NATIONAL LABORATORY; M SHELL; NEVADA; PLASMA DIAGNOSTICS; POLARIZATION; RADIATIONS; SENSITIVITY; SPECTRA; SPECTROMETERS; TESTING; TUNGSTEN; X-RAY SPECTROSCOPY

Citation Formats

Safronova, A S, Kantsyrev, V L, Neill, P, Safronova, U I, Fedin, D A, Ouart, N D, Yilmaz, M F, Osborne, G, Shrestha, I, Williamson, K, Hoppe, T, Harris, C, Beiersdorfer, P, and Hansen, S. The importance of EBIT data for Z-pinch plasma diagnostics. United States: N. p., 2007. Web.
Safronova, A S, Kantsyrev, V L, Neill, P, Safronova, U I, Fedin, D A, Ouart, N D, Yilmaz, M F, Osborne, G, Shrestha, I, Williamson, K, Hoppe, T, Harris, C, Beiersdorfer, P, & Hansen, S. The importance of EBIT data for Z-pinch plasma diagnostics. United States.
Safronova, A S, Kantsyrev, V L, Neill, P, Safronova, U I, Fedin, D A, Ouart, N D, Yilmaz, M F, Osborne, G, Shrestha, I, Williamson, K, Hoppe, T, Harris, C, Beiersdorfer, P, and Hansen, S. Wed . "The importance of EBIT data for Z-pinch plasma diagnostics". United States. doi:. https://www.osti.gov/servlets/purl/972838.
@article{osti_972838,
title = {The importance of EBIT data for Z-pinch plasma diagnostics},
author = {Safronova, A S and Kantsyrev, V L and Neill, P and Safronova, U I and Fedin, D A and Ouart, N D and Yilmaz, M F and Osborne, G and Shrestha, I and Williamson, K and Hoppe, T and Harris, C and Beiersdorfer, P and Hansen, S},
abstractNote = {The results from the last six years of x-ray spectroscopy and spectropolarimetry of high energy density Z-pinch plasmas complemented by experiments with the electron beam ion trap (EBIT) at the Lawrence Livermore National Laboratory (LLNL) are presented. The two topics discussed are the development of M-shell x-ray W spectroscopic diagnostics and K-shell Ti spectropolarimetry of Z-pinch plasmas. The main focus is on radiation from a specific load configuration called an 'X-pinch'. X-pinches are excellent sources for testing new spectral diagnostics and for atomic modelling because of the high density and temperature of the pinch plasmas, which scale from a few {micro}m to several mm in size. They offer a variety of load configurations, which differ in wire connections, number of wires, and wire materials. In this work the study of X-pinches with tungsten wires combined with wires from other, lower-Z materials is reported. Utilizing data produced with the LLNL EBIT at different energies of the electron beam the theoretical prediction of line positions and intensity of M-shell W spectra were tested and calibrated. Polarization-sensitive X-pinch experiments at the University of Nevada, Reno (UNR) provide experimental evidence for the existence of strong electron beams in Ti and Mo X-pinch plasmas and motivate the development of x-ray spectropolarimetry of Z-pinch plasmas. This diagnostic is based on the measurement of spectra recorded simultaneously by two spectrometers with different sensitivity to the linear polarization of the observed lines and compared with theoretical models of polarization-dependent spectra. Polarization-dependent K-shell spectra from Ti X-pinches are presented and compared with model calculations and with spectra generated by a quasi-Maxwellian electron beam at the LLNL EBIT-II electron beam ion trap.},
doi = {},
journal = {Canadian Journal of Physics, vol. 86, no. 1, January 1, 2008, pp. 267-276},
number = 1,
volume = 86,
place = {United States},
year = {Wed Apr 04 00:00:00 EDT 2007},
month = {Wed Apr 04 00:00:00 EDT 2007}
}
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