scholarly journals Electron Cloud at High Beam Currents

2002 ◽  
Author(s):  
Samuel A Heifets
Keyword(s):  
Electron Cloud ◽  
High Beam ◽  
Beam Currents

scholarly journals Development of a radio-frequency quadrupole cooler for high beam currents

2017 ◽  
Vol 20 (12) ◽  
Author(s):  
Ramzi Boussaid ◽  
G. Ban ◽  
G. Quéméner ◽  
Y. Merrer ◽  
J. Lorry
Keyword(s):  
Radio Frequency ◽  
Radio Frequency Quadrupole ◽  
High Beam ◽  
Beam Currents

scholarly journals Issues in Cathode Performance Part 3-Cathode Emitter Material

1995 ◽  
Vol 3 (5) ◽  
pp. 10-11
Author(s):  
Damon Heer
Keyword(s):  
Electron Beam ◽  
High Resolution ◽  
Crystal Orientation ◽  
High Stability ◽  
High Brightness ◽  
High Beam ◽  
Industry Standard ◽  
Small Spot ◽  
Long Lifetime ◽  
Beam Currents

Part 1 of this article series (October 1994 issue) covered the performance features of various tip shapes and explained why the <100> crystal orientation is the industry standard. Part 2 (January/February 1995 issue) covered cathode mounting design and explained how the Mini Vogel Mount cathode design provides high-stability and long-lifetime performance.LaB6 and CeB6 cathodes are used as high-brightness, high-stability, longlifetime cathodes in a variety of electron beam applications. A high-brightness source provides small spot sizes for high resolution and improved analytical results from high beam currents.

A microbeam slit system for high beam currents

2015 ◽  
Vol 348 ◽  
pp. 43-47 ◽  
Author(s):  
T. Vallentin ◽  
M. Moser ◽  
S. Eschbaumer ◽  
C. Greubel ◽  
T. Haase ◽  
...  
Keyword(s):  
High Beam ◽  
Slit System ◽  
Beam Currents

Improved Accuracy for Trace Element Analysis of Al and Ti in Quartz by Electron Probe Microanalysis

2019 ◽  
Vol 25 (1) ◽  
pp. 47-57 ◽  
Author(s):  
Ji-Qiang Cui ◽  
Shui-Yuan Yang ◽  
Shao-Yong Jiang ◽  
Jing Xie
Keyword(s):  
Trace Element ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Trace Element Analysis ◽  
Beam Diameter ◽  
Destructive Testing ◽  
Element Analysis ◽  
Factors Affecting ◽  
High Beam ◽  
Beam Currents

AbstractThe trace elements in quartz, Al and Ti, contain considerable information about mineral genesis, and determining their concentrations is of great importance in geology. Electron probe microanalysis has the advantages of non-destructive testing and high spatial resolution; however, it is a challenge to improve the accuracy and precision of trace element detection using this method. The important factors affecting accuracy include the fragility of quartz lattices at high beam currents and the methods used to determine the background. In this paper, the peaks of Al-Kα and Ti-Kα, and their backgrounds, were found to exhibit intensity variations at high beam currents and small beam diameters; therefore, it is necessary to select a large beam diameter (up to 20 µm) to avoid variations in intensity at high currents (500 nA). For background determination of Al, a multipoint background method is proposed to determine the background value, which greatly improves the accuracy of the results. For Ti, the choice of background measurement does not affect the result. In addition, it is verified that the background obtained from other quartz samples can be used as the background of an unknown quartz sample, which reduces the analysis time and minimizes sample damage.

Effect of Beam Transmission of Stable Isotopes on Online δ13C for SSAMS

Radiocarbon ◽  
2019 ◽  
Vol 61 (5) ◽  
pp. 1573-1579
Author(s):  
G V Ravi Prasad ◽  
Alexander Cherkinsky ◽  
Randy Culp
Keyword(s):  
Stable Isotopes ◽  
Transmission Loss ◽  
Beam Current ◽  
Machine Design ◽  
High Beam ◽  
Different Types ◽  
Beam Transmission ◽  
Beam Currents

ABSTRACTIt is known that 12C beam transmission through the accelerator decreases at high beam currents. This effect depends on machine design and varies across different types of AMS instruments. For beam currents of about 100 μA, the effect is small on the 500 kV tandem CAMS unit, whereas beam saturation is observed for similar high beam currents on the 250 kV SSAMS unit. While this effect is very evident for high 12C beam currents, we have also observed that even the 13C beam is found to suffer modest transmission loss with beam current. As a result, the 13C/12C ratio does not remain constant with beam current. By correcting for the effects of 12C beam saturation and decreased 13C transmission, we have obtained online δ13C values that are more accurate and precise at moderately high beam currents for SSAMS.

The use of the energy-dispersive spectrometer at relatively high beam currents

1982 ◽  
Vol 9 (4) ◽  
pp. 413
Author(s):  
J.M.M. Van Amelsvoort ◽  
H.T.J. Smits ◽  
A.M. Stadhouders
Keyword(s):  
Energy Dispersive Spectrometer ◽  
Energy Dispersive ◽  
High Beam ◽  
Beam Currents
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