Doppler electron velocimetry : notes on creating a practical tool.

Reu, Phillip L. ; Milster, Tom (University of Arizona)

Sandia National Laboratories

关键词: Signal-To-Noise Ratio;    Doppler Radar.;    Electron Beams -Measurement;    Sensitivity;    47 Other Instrumentation;   

DOI  :  10.2172/943861
RP-ID  :  SAND2008-6968
RP-ID  :  AC04-94AL85000
RP-ID  :  943861

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Doppler electron velocimeter (DEV) has been shown to be theoretically possible. This report attempts to answer the next logical question: Is it a practical instrument? The answer hinges upon whether enough electrons are available to create a time-varying Doppler current to be measured by a detector with enough sensitivity and bandwidth. The answer to both of these questions is a qualified yes. A target Doppler frequency of 1 MHz was set as a minimum rate of interest. At this target a theoretical beam current signal-to-noise ratio of 25-to-1 is shown for existing electron holography equipment. A detector is also demonstrated with a bandwidth of 1-MHz at a current of 10 pA. Additionally, a Linnik-type interferometer that would increase the available beam current is shown that would offer a more flexible arrangement for Doppler electron measurements over the traditional biprism.