The slowing down and diffusion of neutrons in finite media according to elementary diffusion theory

Assuming an arbitrary distribution of space charge in the barrier layer of a rectifier, the general form of the current-voltage relation has been derived on both diode and diffusion theory. A connexion, valid for most barriers, between this characteristic and the capacitance-voltage curve has been pointed out, and it has been shown that the Sachs breakdown voltage can be deduced from the latter characteristic. The general relations have been applied to a barrier whose distribution of impurity centres is assumed to establish itself by a diffusion process. Its properties have been investigated, and it has been found that the shapes of the experimental d. c. characteristics, considered in a previous paper (Landsberg 1951 b ), are in the same good agreement with the hypothesis of this barrier as they are with the hypothesis of a Schottky barrier. The difficulties regarding the constants of the rectifiers , as obtained from the experimental curves, are, however, greatly alleviated if the present barriers rather than Schottky’s barrier is assumed. It has been shown that both barriers belong to a whole class of barrier layers whose d. c. and capacitance-voltage curves have the same shape as the corresponding curves for a Schottky barrier.

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Online Privacy Policies and Diffusion Theory Perspectives

Services Marketing Quarterly ◽

10.1300/j396v25n03_04 ◽

2004 ◽

Vol 25 (3) ◽

pp. 53-75 ◽

Cited By ~ 12

Author(s):

Alan D. Smith ◽

William T. Rupp

Keyword(s):

Diffusion Theory ◽

Online Privacy ◽

Privacy Policies ◽

And Diffusion

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A Turbulent History

Solar Energetic Particles - Lecture Notes in Physics ◽

10.1007/978-3-030-66402-2_2 ◽

2021 ◽

pp. 19-48

Author(s):

Donald V. Reames

Keyword(s):

Shock Waves ◽

Coronal Mass Ejections ◽

Energetic Particle ◽

Electron Beams ◽

Diffusion Theory ◽

Plasma Temperature ◽

Solar Energetic Particle ◽

The Sun ◽

Suprathermal Ions ◽

And Diffusion

AbstractLarge solar energetic-particle (SEP) events are clearly associated in time with eruptive phenomena on the Sun, but how? When large SEP events were first observed, flares were the only visible candidate, and diffusion theory was stretched to explain how the particles could spread through space, as widely as observed. The observation of coronal mass ejections (CMEs), and the wide, fast shock waves they can drive, provided better candidates later. Then small events were found with 1000-fold enhancements in 3He/4He that required a different kind of source—should we reconsider flares, or their open-field cousins, solar jets? The 3He-rich events were soon associated with the electron beams that produce type III radio bursts. It seems the radio astronomers knew of both SEP sources all along. Sometimes the distinction between the sources is blurred when shocks reaccelerate residual 3He-rich impulsive suprathermal ions. Eventually, however, we would even begin to measure the source-plasma temperature that helps to better distinguish the SEP sources.

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