Thin-window high-efficiency position sensitive proportional counter for the vacuum flat crystal spectrometers on the Lawrence Livermore National Laboratory electron beam ion trap (abstract)

The electron beam ion trap (EBIT) in Tokyo was constructed about 10 years after the first EBIT at Lawrence Livermore National Laboratory was built, and has been being stably operated since then. In this paper, we present recent experimental activities at the Tokyo EBIT. In particular, experiments utilizing slow, very highly charged ion beams extracted from the EBIT are reported. PACS Nos.: 39.10.+j, 32.30.Rj, 34.50.Dy, 34.80.Kw

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The study of X-ray M-shell spectra of W ions from the Lawrence Livermore National Laboratory Electron Beam Ion Trap

Canadian Journal of Physics ◽

10.1139/p04-053 ◽

2004 ◽

Vol 82 (11) ◽

pp. 931-942 ◽

Cited By ~ 41

Author(s):

P Neill ◽

C Harris ◽

A S Safronova ◽

S Hamasha ◽

S Hansen ◽

...

Keyword(s):

Electron Beam ◽

Energy Range ◽

Spectral Region ◽

Ion Trap ◽

Lawrence Livermore National Laboratory ◽

National Laboratory ◽

Spectral Features ◽

X Ray ◽

Electron Beam Ion Trap

M-shell spectra of W ions have been produced at the Lawrence Livermore National Laboratory EBIT-II electron beam ion trap-II at different energies of the electron beam. A survey has been performed at 2.4, 2.8, and 3.6 keV, and for steps in energy of 100 eV over the 3.94.6 keV energy range. The analysis of 11 W spectra has shown the presence of a wide variety of ionization stages from Se-like to Cr-like W; the appearances of these ionization stages correlate well with the energy of their production. The present paper focuses on the identification of 63 experimental features of W ions in a spectral region from 5 to 6 Å (1 Å = 1010 m) using calculations with inclusion of all ionization stages matching this spectral region. The majority of lines in all spectra have been identified and assigned to the 4f → 3d and 4d → 3p transitions. This is the first work that lists a comprehensive identification of so many resolved spectral features of X-ray M-shell transitions in W ions recorded in such detail in the laboratory. PACS Nos.: 52.58.Lq,32.30.Rj,52.70.La

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The XRS microcalorimeter spectrometer at the Livermore electron beam ion trap

Canadian Journal of Physics ◽

10.1139/p07-147 ◽

2008 ◽

Vol 86 (1) ◽

pp. 231-240 ◽

Cited By ~ 46

Author(s):

F S Porter ◽

B R Beck ◽

P Beiersdorfer ◽

K R Boyce ◽

G V Brown ◽

...

Keyword(s):

Electron Beam ◽

High Performance ◽

Ion Trap ◽

Lawrence Livermore National Laboratory ◽

National Laboratory ◽

High Energy ◽

Operating Conditions ◽

Superconducting Detector ◽

High Quantum Efficiency ◽

Electron Beam Ion Trap

NASA’s X-ray spectrometer (XRS) microcalorimeter instrument has been operating at the electron beam ion trap (EBIT) facility at Lawrence Livermore National Laboratory since July of 2000. The spectrometer is currently undergoing its third major upgrade to become an easy to use and extremely high-performance instrument for a broad range of EBIT experiments. The spectrometer itself is broadband, capable of simultaneously operating from 0.1 to 12 keV and has been operated at up to 100 keV by manipulating its operating conditions. The spectral resolution closely follows the spaceflight version of the XRS, beginning at 10 eV FWHM at 6 keV in 2000, upgraded to 5.5 eV in 2003, and will hopefully be ~3.8 eV in the fall of 2007. Here we review the operating principles of this unique instrument, the extraordinary science that has been performed at EBIT over the last six years, and prospects for future upgrades. Specifically, we discuss upgrades to cover the high-energy band (to at least 100 keV) with a high quantum efficiency detector and prospects for using a new superconducting detector to reach 0.8 eV resolution at 1 keV and 2 eV at 6 keV with high counting rates. PACS Nos.: 52.25.Os, 52.70.La, 95.85.Nv, 32.30.Rj, 07.85.Fv, 78.70.En

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Spectroscopic analysis and modeling of tungsten EBIT and Z-pinch plasma experiments1This article is part of a Special Issue on the 10th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas.

Canadian Journal of Physics ◽

10.1139/p11-026 ◽

2011 ◽

Vol 89 (5) ◽

pp. 599-608 ◽

Cited By ~ 16

Author(s):

G.C. Osborne ◽

A.S. Safronova ◽

V.L. Kantsyrev ◽

U.I. Safronova ◽

P. Beiersdorfer ◽

...

Keyword(s):

Electron Beam ◽

Charge State ◽

Ion Trap ◽

Lawrence Livermore National Laboratory ◽

National Laboratory ◽

Oscillator Strengths ◽

Charge Balance ◽

International Colloquium ◽

Pinch Plasma ◽

Z Pinch

Spectral tungsten data taken on an electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory are analyzed between 3 and 8 Å for electron beam energies between 2.5 and 4.1 keV. The advantage of using charge state balancing with the experimental EBIT spectra for the identification of lines is employed and discussed. Theoretical Hebrew University Lawrence Livermore Atomic Code (HULLAC) modeling is then benchmarked against the experimental EBIT results. In particular, Co-, Ni-, Zn-, Cu-, Ga-, and Ge-like transitions were modeled independently using HULLAC to aid in charge state balancing. This model is then compared with Z-pinch plasma data collected on Zebra, the 1.6 MA pulse power generator located in the Nevada Terawatt Facility at the University of Nevada, Reno. The model is used to calculate charge balance and average ionization levels of these experimental plasma results, with particular focus on planar tungsten arrays.

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Tungsten spectroscopy at the Livermore electron beam ion trap facility1This review is part of a Special Issue on the 10th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas.

Canadian Journal of Physics ◽

10.1139/p11-028 ◽

2011 ◽

Vol 89 (5) ◽

pp. 571-580 ◽

Cited By ~ 42

Author(s):

J. Clementson ◽

P. Beiersdorfer ◽

G.V. Brown ◽

M.F. Gu ◽

H. Lundberg ◽

...

Keyword(s):

Electron Beam ◽

Ion Trap ◽

Lawrence Livermore National Laboratory ◽

National Laboratory ◽

Ion Traps ◽

Oscillator Strengths ◽

Radiative Properties ◽

Experimental Investigations ◽

Fusion Plasma ◽

International Colloquium

The utilization of tungsten spectroscopy for diagnostics of magnetically confined fusion plasmas requires the radiative properties of tungsten ions to be accurately known. At the Lawrence Livermore National Laboratory, a program to gather spectroscopic data on tungsten ions has been initiated with the purpose to study spectral signatures and identify candidate fusion plasma diagnostics. In this paper, an overview of recent results from the Livermore WOLFRAM spectroscopy project is presented, which includes experimental investigations at the EBIT-I and SuperEBIT electron beam ion traps. In particular, the spectra of highly charged M- and L-shell tungsten ions have been studied. These investigations cover energy measurements of n = 2 to n = 2, 3 transitions in Ne-like W64+ through Li-like W71+ ions and soft X-ray measurements of n = 3 to n = 3, 4 transitions in M-shell ions with emphasis on the Ni-like W46+ and Si-like W60+ through Na-like W63+ ions. The measurements are complemented by atomic-structure calculations and spectral modeling using the Flexible Atomic Code (FAC).

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Forbidden Transitions in the Visible Spectra of an Electron Beam Ion Trap (EBIT)

Physica Scripta ◽

10.1088/0031-8949/58/6/009 ◽

1998 ◽

Vol 58 (6) ◽

pp. 599-604 ◽

Cited By ~ 36

Author(s):

E Träbert ◽

P Beiersdorfer ◽

S B Utter ◽

J R Crespo López-Urrutia

Keyword(s):

Electron Beam ◽

Ion Trap ◽

Electron Beam Ion Trap ◽

Visible Spectra ◽

Forbidden Transitions

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Soft-X-ray spectra of highly charged Au ions in an electron-beam ion trap

Canadian Journal of Physics ◽

10.1139/p00-104 ◽

2001 ◽

Vol 79 (2-3) ◽

pp. 153-162 ◽

Cited By ~ 26

Author(s):

E Träbert ◽

P Beiersdorfer ◽

K B Fournier ◽

S B Utter ◽

K L Wong

Keyword(s):

Electron Beam ◽

Beam Energy ◽

Large Scale ◽

Ion Trap ◽

Electron Beam Energy ◽

X Ray ◽

Maximum Charge ◽

Electron Beam Ion Trap ◽

Atomic Structure Calculations ◽

Structure Calculations

Systematic variation of the electron-beam energy in an electron-beam ion trap has been employed to produce soft-X-ray spectra (20 to 60 Å) of Au with well-defined maximum charge states ranging from Br- to Co-like ions. Guided by large-scale relativistic atomic structure calculations, the strongest Δn = 0 (n = 4 to n' = 4) transitions in Rb- to Cu-like ions (Au42+ Au50+) have been identified. PACS Nos.: 32.30Rj, 39.30+w, 31.50+w, 32.20R

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