Nightside electron flux measurements at Mars by the Phobos-2 HARP instrument

1995 ◽  
Vol 22 (7) ◽  
pp. 863-866 ◽  
Author(s):  
N. Shutte ◽  
K. Gringauz ◽  
P. Király ◽  
G. Kotova ◽  
A. F. Nagy ◽  
...  
Keyword(s):  
Electron Flux ◽  
Flux Measurements

Plasma Sheet Convection Velocities Inferred From Electron Flux Measurements at Synchronous Altitude

Radio Science ◽  
1971 ◽  
Vol 6 (2) ◽  
pp. 305-313 ◽  
Author(s):  
E. G. Shelley ◽  
R. G. Johnson ◽  
R. D. Sharp
Keyword(s):  
Plasma Sheet ◽  
Electron Flux ◽  
Flux Measurements

Application of passive methods for electron flux measurements regarding to 238U electron-disintegration studies

2018 ◽  
Vol 317 (2) ◽  
pp. 731-737 ◽  
Author(s):  
C. Tziaka ◽  
S. Stoulos ◽  
A. Makridou ◽  
I. Stamatelatos ◽  
M. Fragopoulou ◽  
...  
Keyword(s):  
Electron Flux ◽  
Flux Measurements

scholarly journals A background correction algorithm for Van Allen Probes MagEIS electron flux measurements

2015 ◽  
Vol 120 (7) ◽  
pp. 5703-5727 ◽  
Author(s):  
S. G. Claudepierre ◽  
T. P. O'Brien ◽  
J. B. Blake ◽  
J. F. Fennell ◽  
J. L. Roeder ◽  
...  
Keyword(s):  
Electron Flux ◽  
Background Correction ◽  
Correction Algorithm ◽  
Van Allen Probes ◽  
Flux Measurements

scholarly journals Faraday Cup for Electron Flux Measurements on the Microtron MT 25

10.14311/176 ◽  
2001 ◽  
Vol 41 (1) ◽  
Author(s):  
M. Vognar ◽  
Č. Šimáně ◽  
D. Chvátil
Keyword(s):  
Electron Beam ◽  
Precise Measurement ◽  
Electron Flux ◽  
Measuring Line ◽  
Faraday Cup ◽  
Flux Measurements ◽  
Beam Currents ◽  
Physical Engineering ◽  
Entry Window

The basic criteria for constructing of an evacuated Faraday cup for precise measurement of 5 to 25 MeV electron beam currents in air from a microtron are established. The Faraday cup, built in the microtron laboratory of the Faculty of Nuclear Sciences and Physical Engineering of CTU Prague, is described together with the electronic chain and its incorporation in the measuring line on the beam. Measures to reduce the backward escape of electrons are explained. The range of currents is from 10–5 to 10–10 A. The diameter of the Al entry window of the Faraday cup is 1.8 cm, and its area is 2.54 cm2. The thickness of the entry window is 0.1 mm.

Equatorial pitch angle distributions in Earth's radiation belts: an empirical model from Van Allen Probes data

2020 ◽  
Author(s):  
Artem Smirnov ◽  
Yuri Shprits ◽  
Hayley Allison ◽  
Nikita Aseev
Keyword(s):  
Solar Activity ◽  
Empirical Model ◽  
Pitch Angle ◽  
Electron Flux ◽  
Dynamic Pressure ◽  
Radiation Belts ◽  
Data Set ◽  
Van Allen Probes ◽  
Flux Measurements ◽  
Solar Wind Parameters

<p><span>Earth’s radiation belts comprise complex and dynamic systems, depending substantially on solar activity. The pitch angle distributions (PADs) play an important role for radiation belts modelling, as they yield information on the particle transport, source and loss processes. Yet, many missions flying in the radiation belts provide omni-directional or uni-directional electron flux measurements and do not resolve pitch angles. We propose an empirical model of the equatorial PADs and a method to retrieve PADs from omni-directional flux measurements at different energies and locations along the inclined orbits. We use the entire dataset of MagEIS and REPT instruments aboard the Van Allen Probes (RBSP) mission to analyze the equatorial pitch angle distributions in the energy range from 30 keV to 6.2 MeV. The fitting method resolves all main types of PADs, including butterfly and cap distributions, and the resulting coefficients are directly related to the PAD shapes. The developed model can be used to obtain pitch angle resolved fluxes for GPS, Arase and other missions. The proposed algorithm is applied to the GPS electron flux data set to obtain the pitch-angle resolved fluxes, which are compared to the RBSP data at a number of GPS-RBSP conjunctions. The proposed model also allows one to reconstruct the pitch-angle resolved data using LEO measurements. The dynamics of the fitting coefficients based on solar activity is discussed with respect to AE, Kp, Dst indices and solar wind parameters: velocity, density and dynamic pressure.</span></p>

Electron-Channelling Patterns: Principles and Techniques

1976 ◽  
Vol 34 ◽  
pp. 400-401
Author(s):  
David C. Joy
Keyword(s):  
Crystal Structure ◽  
Electron Flux ◽  
Lattice Structure ◽  
Incident Beam ◽  
Bloch Wave ◽  
Crystalline Solid ◽  
Angle Of Incidence ◽  
Electron Channelling ◽  
Regular Arrangement ◽  
Backscattered Signals

In a crystalline solid the regular arrangement of the lattice structure influences the interaction of the incident beam with the specimen, leading to changes in both the transmitted and backscattered signals when the angle of incidence of the beam to the specimen is changed. For the simplest case the electron flux inside the specimen can be visualized as the sum of two, standing wave distributions of electrons (Fig. 1). Bloch wave 1 is concentrated mainly between the atom rows and so only interacts weakly with them. It is therefore transmitted well and backscattered weakly. Bloch wave 2 is concentrated on the line of atom centers and is therefore transmitted poorly and backscattered strongly. The ratio of the excitation of wave 1 to wave 2 varies with the angle between the incident beam and the crystal structure.

Anisotropy of damage productions in electron irradiated molybdenum

1978 ◽  
Vol 36 (1) ◽  
pp. 354-355
Author(s):  
K. Izui ◽  
S. Furuno ◽  
H. Otsu ◽  
T. Nishida ◽  
H. Maeta
Keyword(s):  
Electron Flux ◽  
Threshold Energy ◽  
High Energy ◽  
Voltage Electron ◽  
High Voltage Electron Microscope ◽  
Displacement Threshold ◽  
The Mean ◽  
Channeling Effect ◽  
Different Origins ◽  
Threshold Energies

Anisotropy of damage productions in crystals due to high energy electron bombardment are caused from two different origins. One is an anisotropic displacement threshold energy, and the other is an anisotropic distribution of electron flux near the atomic rows in crystals due to the electron channeling effect. By the n-beam dynamical calculations for germanium and molybdenum we have shown that electron flux at the atomic positions are from ∽4 to ∽7 times larger than the mean incident flux for the principal zone axis directions of incident 1 MeV electron beams, and concluded that such a locally increased electron flux results in an enhanced damage production. The present paper reports the experimental evidence for the enhanced damage production due to the locally increased electron flux and also the results of measurements of the displacement threshold energies for the <100>,<110> and <111> directions in molybdenum crystals by using a high voltage electron microscope.

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