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Title: A tetrode based fast pulsed microwave source for electron cyclotron resonance breakdown experiments

Abstract

To study electron cylotron resonance (ECR) breakdown and afterglow plasma in an experimental linear plasma system, a pulsed microwave source with rapid rise and fall of microwave power is desired. A pulsed microwave source with fast rise and fall capability for ECR breakdown experiments has been designed and tested for performance in the system. A tetrode, controlled by a modulator card, is used as a fast switch to initiate microwave power from a conventional magnetron operating at 2.45 GHz. The typical rise time of microwave power is {approx}3 {mu}s and a fall time of {approx}10 {mu}s. Using this scheme in a realistic pulsed microwave source at 800 W power, ECR breakdown of neutral gas is achieved and the plasma delay and fall time are observed from the plasma density measurements using a Langmuir probe. The design details of the fast rise pulsed microwave source are presented in this article with initial experimental results.

Authors:
; ; ;  [1]
  1. Institute for Plasma Research, Bhat, Gandhinagar, Gujarat - 382 428 (India)
Publication Date:
OSTI Identifier:
20953257
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 2; Other Information: DOI: 10.1063/1.2671793; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AFTERGLOW; BREAKDOWN; DESIGN; ELECTRON CYCLOTRON-RESONANCE; ELECTRONS; GHZ RANGE 01-100; HIGH-FREQUENCY DISCHARGES; LANGMUIR PROBE; MAGNETRONS; MICROWAVE RADIATION; PERFORMANCE; PLASMA; PLASMA DENSITY; PULSE RISE TIME; SWITCHES

Citation Formats

Yadav, Vipin K., Sathyanarayana, K., Purohit, D., and Bora, D. A tetrode based fast pulsed microwave source for electron cyclotron resonance breakdown experiments. United States: N. p., 2007. Web. doi:10.1063/1.2671793.
Yadav, Vipin K., Sathyanarayana, K., Purohit, D., & Bora, D. A tetrode based fast pulsed microwave source for electron cyclotron resonance breakdown experiments. United States. doi:10.1063/1.2671793.
Yadav, Vipin K., Sathyanarayana, K., Purohit, D., and Bora, D. Thu . "A tetrode based fast pulsed microwave source for electron cyclotron resonance breakdown experiments". United States. doi:10.1063/1.2671793.
@article{osti_20953257,
title = {A tetrode based fast pulsed microwave source for electron cyclotron resonance breakdown experiments},
author = {Yadav, Vipin K. and Sathyanarayana, K. and Purohit, D. and Bora, D.},
abstractNote = {To study electron cylotron resonance (ECR) breakdown and afterglow plasma in an experimental linear plasma system, a pulsed microwave source with rapid rise and fall of microwave power is desired. A pulsed microwave source with fast rise and fall capability for ECR breakdown experiments has been designed and tested for performance in the system. A tetrode, controlled by a modulator card, is used as a fast switch to initiate microwave power from a conventional magnetron operating at 2.45 GHz. The typical rise time of microwave power is {approx}3 {mu}s and a fall time of {approx}10 {mu}s. Using this scheme in a realistic pulsed microwave source at 800 W power, ECR breakdown of neutral gas is achieved and the plasma delay and fall time are observed from the plasma density measurements using a Langmuir probe. The design details of the fast rise pulsed microwave source are presented in this article with initial experimental results.},
doi = {10.1063/1.2671793},
journal = {Review of Scientific Instruments},
number = 2,
volume = 78,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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