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Title: Measurements of the high confinement mode pedestal region on Alcator C-Mod

Abstract

Measurements of the steep transport barrier at the edge of the Alcator C-Mod tokamak [I. H. Hutchinson {ital et al.}, Phys. Plasmas {bold 1}, 1511 (1994)] are presented. The parameters at the top of this barrier are in the range T{sub e}=150{endash}750 eV and n{sub e}=0.5{minus}3.3{times}10{sup 20} m{sup {minus}3}, depending on the confinement regime. Type III edge localized modes (ELMs) have an upper temperature limit. T{sub e} pedestal profiles show a barrier width {Delta}{sub T}{approx_equal}8 mm. Soft x-ray emissivity profiles are narrower, with {Delta}=2{endash}4 mm. Edge currents are calculated to alter the ideal stability boundary favorably, leading to ideally stable pedestal profiles. High frequency, broadband, edge density fluctuations are sometimes observed in H-mode (high-confinement mode) and are associated with enhanced particle transport. Coherent magnetic fluctuations localized near the pedestal are also seen. {copyright} {ital 1998 American Institute of Physics.}

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]
  1. Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
Publication Date:
OSTI Identifier:
610670
Report Number(s):
CONF-971103-
Journal ID: PHPAEN; ISSN 1070-664X; TRN: 98:005372
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 5; Journal Issue: 5; Conference: 39. annual meeting of the Division of Plasma Physics of the American Physical Society, Pittsburgh, PA (United States), 17-21 Nov 1997; Other Information: PBD: May 1998
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; PLASMA INSTABILITY; PLASMA DENSITY; ALCATOR DEVICE; PLASMA CONFINEMENT; CHARGED-PARTICLE TRANSPORT; PLASMA DIAGNOSTICS

Citation Formats

Hubbard, A E, Boivin, R L, Granetz, R S, Greenwald, M, Hutchinson, I H, Irby, J H, In, Y, Kesner, J, LaBombard, B, Lin, Y, Rice, J E, Sunn Pedersen, T, Snipes, J A, Stek, P C, Takase, Y, Wolfe, S M, and Wukitch, S. Measurements of the high confinement mode pedestal region on Alcator C-Mod. United States: N. p., 1998. Web. doi:10.1063/1.872843.
Hubbard, A E, Boivin, R L, Granetz, R S, Greenwald, M, Hutchinson, I H, Irby, J H, In, Y, Kesner, J, LaBombard, B, Lin, Y, Rice, J E, Sunn Pedersen, T, Snipes, J A, Stek, P C, Takase, Y, Wolfe, S M, & Wukitch, S. Measurements of the high confinement mode pedestal region on Alcator C-Mod. United States. https://doi.org/10.1063/1.872843
Hubbard, A E, Boivin, R L, Granetz, R S, Greenwald, M, Hutchinson, I H, Irby, J H, In, Y, Kesner, J, LaBombard, B, Lin, Y, Rice, J E, Sunn Pedersen, T, Snipes, J A, Stek, P C, Takase, Y, Wolfe, S M, and Wukitch, S. 1998. "Measurements of the high confinement mode pedestal region on Alcator C-Mod". United States. https://doi.org/10.1063/1.872843.
@article{osti_610670,
title = {Measurements of the high confinement mode pedestal region on Alcator C-Mod},
author = {Hubbard, A E and Boivin, R L and Granetz, R S and Greenwald, M and Hutchinson, I H and Irby, J H and In, Y and Kesner, J and LaBombard, B and Lin, Y and Rice, J E and Sunn Pedersen, T and Snipes, J A and Stek, P C and Takase, Y and Wolfe, S M and Wukitch, S},
abstractNote = {Measurements of the steep transport barrier at the edge of the Alcator C-Mod tokamak [I. H. Hutchinson {ital et al.}, Phys. Plasmas {bold 1}, 1511 (1994)] are presented. The parameters at the top of this barrier are in the range T{sub e}=150{endash}750 eV and n{sub e}=0.5{minus}3.3{times}10{sup 20} m{sup {minus}3}, depending on the confinement regime. Type III edge localized modes (ELMs) have an upper temperature limit. T{sub e} pedestal profiles show a barrier width {Delta}{sub T}{approx_equal}8 mm. Soft x-ray emissivity profiles are narrower, with {Delta}=2{endash}4 mm. Edge currents are calculated to alter the ideal stability boundary favorably, leading to ideally stable pedestal profiles. High frequency, broadband, edge density fluctuations are sometimes observed in H-mode (high-confinement mode) and are associated with enhanced particle transport. Coherent magnetic fluctuations localized near the pedestal are also seen. {copyright} {ital 1998 American Institute of Physics.}},
doi = {10.1063/1.872843},
url = {https://www.osti.gov/biblio/610670}, journal = {Physics of Plasmas},
number = 5,
volume = 5,
place = {United States},
year = {Fri May 01 00:00:00 EDT 1998},
month = {Fri May 01 00:00:00 EDT 1998}
}