Measurement of spiraling in a magnetically confined electron beam for use in collision studies

1974 ◽  
Vol 45 (4) ◽  
pp. 538-544 ◽  
Author(s):  
P. O. Taylor ◽  
K. T. Dolder ◽  
W. E. Kauppila ◽  
G. H. Dunn
Keyword(s):  
Electron Beam ◽  
Magnetically Confined

scholarly journals Spectra of Ga-Like to Cu-Like Praseodymium and Neodymium Ions Observed in the Large Helical Device

Atoms ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 46
Author(s):  
Chihiro Suzuki ◽  
Fumihiro Koike ◽  
Izumi Murakami ◽  
Tetsutarou Oishi ◽  
Naoki Tamura
Keyword(s):  
Electron Beam ◽  
High Temperature ◽  
Ion Trap ◽  
Extreme Ultraviolet ◽  
Spectral Feature ◽  
Spectral Lines ◽  
Electron Beam Ion Trap ◽  
Magnetically Confined ◽  
First Time ◽  
Charged Ions

Extreme ultraviolet (EUV) spectra of highly charged praseodymium (Pr) and neodymium (Nd) ions have been investigated in optically thin high-temperature plasmas produced in the Large Helical Device (LHD), a magnetically confined torus device for fusion research. Discrete spectral lines emitted mainly from highly charged ions having 4s or 4p outermost electrons were observed in plasmas with electron temperatures of 0.8–1.8 keV. Most of the isolated lines of Ga-like to Cu-like Nd ions were identified by a comparison with the recent data recorded in an electron beam ion trap (EBIT). The isolated lines of Pr ions corresponding to the identified lines of Nd ions were easily assigned from a similarity of the spectral feature for these two elements. As a result, some of the lines of Pr ions have been newly identified experimentally for the first time in this study.

Spectroscopy on magnetically confined plasmas using electron beam ion trap spectrometers

2008 ◽  
Vol 86 (1) ◽  
pp. 307-313 ◽  
Author(s):  
A T Graf ◽  
S Brockington ◽  
R Horton ◽  
S Howard ◽  
D Hwang ◽  
...  
Keyword(s):  
Electron Beam ◽  
Ion Trap ◽  
Confined Plasmas ◽  
Transmission Grating ◽  
Compact Toroid ◽  
Grating Spectrometer ◽  
Electron Beam Ion Trap ◽  
Magnetically Confined ◽  
Physics Experiment ◽  
The University

Multiple spectrometers originally designed for and used at the University of California Lawrence Livermore National Laboratory’s electron beam ion trap have found use at various magnetically confined plasma facilities. Three examples will be described. First is a soft X-ray/EUV grating spectrometer (6–150 Å), which is operating at the National Spherical Torus Experiment. Second is an EUV spectrometer with wavelength coverage up to 400 Å, which has just recently started operating at the Sustained Spheromak Physics Experiment. The last is a high-resolution transmission-grating spectrometer for visible light that has been used at the Compact Toroid Injection Experiment and is currently at the Alcator C-Mod tokamak.PACS Nos.: 39.30.+w, 52.55.–s, 32.30.Rj, 07.60.Rd, 52.70.La

Electron collision studies with trapped positive ions

1966 ◽  
Vol 261 (1115) ◽  
pp. 33-65 ◽  
Keyword(s):  
Electron Beam ◽  
Space Charge ◽  
Cross Section ◽  
Noble Gases ◽  
Electron Collision ◽  
Ion Currents ◽  
Appearance Potential ◽  
Positive Ions ◽  
Magnetically Confined ◽  
Ion Effects

Positive ions have been trapped for periods of ca. 100 /zs within the space charge of a magnetically confined electron beam, ionized by this beam and detected mass-spectrometrically. The theory of the trap is developed and compared at many points with experiment. Cross section functions are given for the ionization of Ne +, Ar + , Kr + , Xe + , and the dissociation of CO + by electrons; the ionization of Ne 2 + and CO + by electrons is also investigated. From measurements of fragment ion currents CH 2 + , CH + from methane, it is shown that the dissociation of CH 4 + by electrons can contribute unwanted effects interfering with the appearance potential of the fragment ion. Effects due to excitation of ions by electrons are observed in the noble gases.

scholarly journals Magnetically confined electron beam system for high resolution electron transmission-beam experiments

2018 ◽  
Vol 89 (6) ◽  
pp. 063105 ◽  
Author(s):  
A. I. Lozano ◽  
J. C. Oller ◽  
K. Krupa ◽  
F. Ferreira da Silva ◽  
P. Limão-Vieira ◽  
...  
Keyword(s):  
Electron Beam ◽  
High Resolution ◽  
Electron Transmission ◽  
Beam System ◽  
Resolution Electron ◽  
Magnetically Confined

Techniques for Transmission Electron Microscopy of Fiber-Matrix Interfaces in Aluminum Alloy-Boron Composites by Ion Erosio

1971 ◽  
Vol 29 ◽  
pp. 204-205
Author(s):  
G. G. Shaw
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Aluminum Alloy ◽  
Electron Beam ◽  
Pure Aluminum ◽  
Ion Milling ◽  
Transmission Electron ◽  
Fiber Matrix ◽  
Ion Erosion ◽  
Row Of Fibers

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.

Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

1982 ◽  
Vol 40 ◽  
pp. 78-79
Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser
Keyword(s):  
Electron Beam ◽  
Fatty Acid ◽  
Inelastic Scattering ◽  
Temperature Dependence ◽  
Structural Damage ◽  
Direct Result ◽  
Second Step ◽  
Strong Temperature Dependence ◽  
Electron Dose ◽  
Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

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