Analysis of Wien filter spectra from Hall thruster plumes

2015 ◽  
Vol 86 (7) ◽  
pp. 073502 ◽  
Author(s):  
Wensheng Huang ◽  
Rohit Shastry
Keyword(s):  
Author(s):  
Jordan H. Hsieh ◽  
Yueh-Heng Li ◽  
Hou-Yi Lee ◽  
Ming-Hsueh Shen
Keyword(s):  

Author(s):  
P. E. Batson

In recent years,instrumentation for electron energy loss spectroscopy (EELS) has been steadily improved to increase energy resolution and collection efficiency. At present 0.40eV at 10mR collection half angle is available with commercial magnetic sectors (e.g. Gatan, Inc. and VG Microscopes, Ltd.), and 70meV at 10mR has been demonstrated by use of a Wien filter within a large deceleration field. When these high resolution spectrometers are coupled to the modern small electron probe instrument, we obtain a tool which promises to reveal local changes in bandstructure and bonding near defects and interfaces in heterogeneous materials.Unfortunately, typical electron sources have intrinsic energy widths which limit attainable spectroscopic resolution in the absence of some monochromation system. For instance, the W thermal emitter has a half width of about 1eV.


Author(s):  
F. Hasselbach ◽  
A. Schäfer

Möllenstedt and Wohland proposed in 1980 two methods for measuring the coherence lengths of electron wave packets interferometrically by observing interference fringe contrast in dependence on the longitudinal shift of the wave packets. In both cases an electron beam is split by an electron optical biprism into two coherent wave packets, and subsequently both packets travel part of their way to the interference plane in regions of different electric potential, either in a Faraday cage (Fig. 1a) or in a Wien filter (crossed electric and magnetic fields, Fig. 1b). In the Faraday cage the phase and group velocity of the upper beam (Fig.1a) is retarded or accelerated according to the cage potential. In the Wien filter the group velocity of both beams varies with its excitation while the phase velocity remains unchanged. The phase of the electron wave is not affected at all in the compensated state of the Wien filter since the electron optical index of refraction in this state equals 1 inside and outside of the Wien filter.


1997 ◽  
Author(s):  
W. Hargus, Jr. ◽  
R. Cedolin ◽  
N. Meezan ◽  
M. Cappelli ◽  
W. Hargus, Jr. ◽  
...  

Author(s):  
David Liu ◽  
Richard Huffman ◽  
Richard Branam ◽  
William Hargus
Keyword(s):  

Author(s):  
LEONARDO BRAGA ◽  
Rodrigo Cerda ◽  
Rodrigo Alkimim Faria Alves

2000 ◽  
Author(s):  
B. Pote ◽  
V. Hruby ◽  
J. Monheiser
Keyword(s):  

2021 ◽  
Vol 129 (19) ◽  
pp. 193301
Author(s):  
Ioannis G. Mikellides ◽  
Alejandro Lopez Ortega

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