Thermal Electron Capped Hemisphere Spectrometer (TECHS) for Ionospheric Studies

Author(s):  
C. J. Pollock ◽  
V. N. Coffey ◽  
J. D. England ◽  
N. G. Martinez ◽  
T. E. Moore ◽  
...  
Keyword(s):  
Author(s):  
S.J. Krause ◽  
W.W. Adams

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.


1997 ◽  
Vol 101 (37) ◽  
pp. 6876-6882 ◽  
Author(s):  
U. Ammon ◽  
C. Chiorboli ◽  
W. Dümler ◽  
G. Grampp ◽  
F. Scandola ◽  
...  

1986 ◽  
Vol 26 (8) ◽  
pp. 1106-1111 ◽  
Author(s):  
R. Bartiromo ◽  
M. Hesse ◽  
F.X. Söldner ◽  
R. Burhenn ◽  
G. Fussmann ◽  
...  

1982 ◽  
Vol 86 (8) ◽  
pp. 1240-1242 ◽  
Author(s):  
Lucia M. Babcock ◽  
Gerald E. Streit

2015 ◽  
Vol 11 (S320) ◽  
pp. 239-242
Author(s):  
Jianxia Cheng ◽  
Mingde Ding

AbstractSolar flares produce radiations in very broad wavelengths. Spectra can supply us abundant information about the local plasma, such as temperature, density, mass motion and so on. Strong chromospheric lines, like the most studied Hα and Ca II 8542 Å lines are formed under conditions of departures from local thermodynamic equilibrium in the lower atmosphere subject to flare heating. Understanding how these lines are formed is very useful for us to correctly interpret the observations. In this paper, we try to figure out the response of chromospheric lines heated by different periodic non-thermal electron beams. Our results are based on radiative hydrodynamic simulations. We vary the periods of electron beam injection from 1.25 s to 20 s. We compare the response times to different heating parameters. Possible explanations are discussed.


2005 ◽  
Vol 12 (5) ◽  
pp. 052511 ◽  
Author(s):  
G. Taylor ◽  
P. C. Efthimion ◽  
B. P. LeBlanc ◽  
M. D. Carter ◽  
J. B. Caughman ◽  
...  

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