scholarly journals 6D phase space electron beam analysis and machine sensitivity studies for ELI-NP GBS

Author(s):  
A. Giribono ◽  
A. Bacci ◽  
C. Curatolo ◽  
I. Drebot ◽  
L. Palumbo ◽  
...  
2003 ◽  
Vol 10 (1/2) ◽  
pp. 45-52 ◽  
Author(s):  
R. E. Ergun ◽  
L. Andersson ◽  
C. W. Carlson ◽  
D. L. Newman ◽  
M. V. Goldman

Abstract. Direct observations of magnetic-field-aligned (parallel) electric fields in the downward current region of the aurora provide decisive evidence of naturally occurring double layers. We report measurements of parallel electric fields, electron fluxes and ion fluxes related to double layers that are responsible for particle acceleration. The observations suggest that parallel electric fields organize into a structure of three distinct, narrowly-confined regions along the magnetic field (B). In the "ramp" region, the measured parallel electric field forms a nearly-monotonic potential ramp that is localized to ~ 10 Debye lengths along B. The ramp is moving parallel to B at the ion acoustic speed (vs) and in the same direction as the accelerated electrons. On the high-potential side of the ramp, in the "beam" region, an unstable electron beam is seen for roughly another 10 Debye lengths along B. The electron beam is rapidly stabilized by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes. The "wave" region is physically separated from the ramp by the beam region. Numerical simulations reproduce a similar ramp structure, beam region, electrostatic turbulence region and plasma characteristics as seen in the observations. These results suggest that large double layers can account for the parallel electric field in the downward current region and that intense electrostatic turbulence rapidly stabilizes the accelerated electron distributions. These results also demonstrate that parallel electric fields are directly associated with the generation of large-amplitude electron phase-space holes and plasma waves.


2000 ◽  
Vol 46 (2) ◽  
pp. 269-286 ◽  
Author(s):  
J J Janssen ◽  
E W Korevaar ◽  
L J van Battum ◽  
P R M Storchi ◽  
H Huizenga

1977 ◽  
Author(s):  
Kai Chang ◽  
Joseph E. Rowe

1999 ◽  
Vol 5 (S2) ◽  
pp. 108-109
Author(s):  
K. L. Merkle ◽  
L. J. Thompson

The observation of atomic-scale structures of grain boundaries (GBs) via axial illumination HREM has been largely restricted to tilt GBs, due to the requirement that the electron beam be parallel to a low-index zone axis on both sides of the interface. This condition can be fulfilled for all tilt GBs with misorientation about a low-index direction. The information obtained through HREM studies in many materials has brought important insights concerning the atomic-scale structure of such boundaries. However, it is well known that tilt GBs occupy only an infinitesimally small fraction of the 5-dimensional phase space which describes the macroscopic geometry of all GBs. Therefore, although tilt GBs are very important due to their low energy, it would be usefulto also study twist GBs and general GBs that contain twist and tilt components.We have prepared thin-film Au samples by an epitaxy technique in which (01l) and (001) grains are grown side by side.


1973 ◽  
Vol 30 (3) ◽  
pp. 75-77 ◽  
Author(s):  
K. W. Gentle ◽  
J. Lohr

2013 ◽  
Vol 101 (1) ◽  
pp. 10008 ◽  
Author(s):  
V. Petrillo ◽  
I. Chaikovska ◽  
C. Ronsivalle ◽  
A. R. Rossi ◽  
L. Serafini ◽  
...  

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