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Title: Particle and heat flux measurements in PDX edge plasmas

Abstract

This paper describes the use of novel combined Langmuir-calorimeter probes to measure edge plasma conditions near the midplane in PDX. The probes consisted of up to five Langmuir probes and up to two calorimeters. Single and double probe characteristics yield n/sub e/ and T/sub e/ which are compared with that derived from a triple probe analysis. The calorimeters measure heat flux in the electron and ion drift directions. This paper presents time-resolved radial profiles of n/sub e/, T/sub e/, V/sub F/ (floating potential), and P (heat flux) during high power neutral beam-heated, single-null discharges and circular scoop limiter discharges. The temporal dependence of these quantities displays the previous observed behavior with respect to gross discharge characteristics; however, an additional dependence on confinement mode has been observed. During the H-mode of energy confinement, a transient depression of n/sub e/, T/sub e/, and P occurs in the scrape-off plasma.

Authors:
;
Publication Date:
Research Org.:
Princeton Univ., NJ (USA). Plasma Physics Lab.
OSTI Identifier:
5471599
Report Number(s):
PPPL-2065
ON: DE84004305
DOE Contract Number:
AC02-76CH03073
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; PDX DEVICES; PLASMA DIAGNOSTICS; PLASMA SHEATH; CALORIMETERS; LANGMUIR PROBE; ELECTRON DENSITY; ELECTRON TEMPERATURE; HEAT TRANSFER; CLOSED PLASMA DEVICES; ELECTRIC PROBES; ENERGY TRANSFER; MEASURING INSTRUMENTS; PROBES; THERMONUCLEAR DEVICES; TOKAMAK DEVICES; 700102* - Fusion Energy- Plasma Research- Diagnostics

Citation Formats

Budny, R., and Manos, D. Particle and heat flux measurements in PDX edge plasmas. United States: N. p., 1983. Web. doi:10.2172/5471599.
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Budny, R., & Manos, D. Particle and heat flux measurements in PDX edge plasmas. United States. doi:10.2172/5471599.
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Budny, R., and Manos, D. Thu . "Particle and heat flux measurements in PDX edge plasmas". United States. doi:10.2172/5471599. https://www.osti.gov/servlets/purl/5471599.
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@article{osti_5471599,
title = {Particle and heat flux measurements in PDX edge plasmas},
author = {Budny, R. and Manos, D.},
abstractNote = {This paper describes the use of novel combined Langmuir-calorimeter probes to measure edge plasma conditions near the midplane in PDX. The probes consisted of up to five Langmuir probes and up to two calorimeters. Single and double probe characteristics yield n/sub e/ and T/sub e/ which are compared with that derived from a triple probe analysis. The calorimeters measure heat flux in the electron and ion drift directions. This paper presents time-resolved radial profiles of n/sub e/, T/sub e/, V/sub F/ (floating potential), and P (heat flux) during high power neutral beam-heated, single-null discharges and circular scoop limiter discharges. The temporal dependence of these quantities displays the previous observed behavior with respect to gross discharge characteristics; however, an additional dependence on confinement mode has been observed. During the H-mode of energy confinement, a transient depression of n/sub e/, T/sub e/, and P occurs in the scrape-off plasma.},
doi = {10.2172/5471599},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 1983},
month = {Thu Dec 01 00:00:00 EST 1983}
}
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Technical Report:
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DOI:  10.2172/5471599
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