Experimental study of reversed shear Alfvén eigenmodes during the current ramp in the Alcator C-Mod tokamak

E. M. Edlund; M. Porkolab; G. J. Kramer; L. Lin; Y. Lin; N. Tsujii; S. J. Wukitch

doi:10.1088/0741-3335/52/11/115003

Experimental study of reversed shear Alfvén eigenmodes during the current ramp in the Alcator C-Mod tokamak

E. M. Edlund, M. Porkolab, G. J. Kramer, L. Lin, Y. Lin, N. Tsujii, S. J. Wukitch

PPPL Tokamak Expermntl Science

Research output: Contribution to journal › Article › peer-review

8 Scopus citations

Abstract

Experiments conducted in the Alcator C-Mod tokamak have explored the physics of reversed shear Alfvén eigenmodes (RSAEs) during the current ramp. The frequency evolution of the RSAEs during the current ramp provides a constraint on the evolution of q_min, a result which is important in transport modeling and for comparison with other diagnostics which directly measure the magnetic field line structure. Additionally, a scaling of the RSAE minimum frequency with the sound speed is used to derive bounds on the adiabatic index, a measure of the plasma compressibility. This scaling places the adiabatic index at 1.40±0.15 and supports the kinetic calculation of separate electron and ion compressibilities with an ion adiabatic index close to 7/4.

Original language	English (US)
Article number	115003
Journal	Plasma Physics and Controlled Fusion
Volume	52
Issue number	11
DOIs	https://doi.org/10.1088/0741-3335/52/11/115003
State	Published - Nov 2010

All Science Journal Classification (ASJC) codes

Nuclear Energy and Engineering
Condensed Matter Physics

Access to Document

10.1088/0741-3335/52/11/115003

Cite this

@article{ffc0ca1018004a318094ab72aa2a5d7a,

title = "Experimental study of reversed shear Alfv{\'e}n eigenmodes during the current ramp in the Alcator C-Mod tokamak",

abstract = "Experiments conducted in the Alcator C-Mod tokamak have explored the physics of reversed shear Alfv{\'e}n eigenmodes (RSAEs) during the current ramp. The frequency evolution of the RSAEs during the current ramp provides a constraint on the evolution of qmin, a result which is important in transport modeling and for comparison with other diagnostics which directly measure the magnetic field line structure. Additionally, a scaling of the RSAE minimum frequency with the sound speed is used to derive bounds on the adiabatic index, a measure of the plasma compressibility. This scaling places the adiabatic index at 1.40±0.15 and supports the kinetic calculation of separate electron and ion compressibilities with an ion adiabatic index close to 7/4.",

author = "Edlund, \{E. M.\} and M. Porkolab and Kramer, \{G. J.\} and L. Lin and Y. Lin and N. Tsujii and Wukitch, \{S. J.\}",

year = "2010",

month = nov,

doi = "10.1088/0741-3335/52/11/115003",

language = "English (US)",

volume = "52",

journal = "Plasma Physics and Controlled Fusion",

issn = "0741-3335",

publisher = "IOP Publishing Ltd.",

number = "11",

}

TY - JOUR

T1 - Experimental study of reversed shear Alfvén eigenmodes during the current ramp in the Alcator C-Mod tokamak

AU - Edlund, E. M.

AU - Porkolab, M.

AU - Kramer, G. J.

AU - Lin, L.

AU - Lin, Y.

AU - Tsujii, N.

AU - Wukitch, S. J.

PY - 2010/11

Y1 - 2010/11

N2 - Experiments conducted in the Alcator C-Mod tokamak have explored the physics of reversed shear Alfvén eigenmodes (RSAEs) during the current ramp. The frequency evolution of the RSAEs during the current ramp provides a constraint on the evolution of qmin, a result which is important in transport modeling and for comparison with other diagnostics which directly measure the magnetic field line structure. Additionally, a scaling of the RSAE minimum frequency with the sound speed is used to derive bounds on the adiabatic index, a measure of the plasma compressibility. This scaling places the adiabatic index at 1.40±0.15 and supports the kinetic calculation of separate electron and ion compressibilities with an ion adiabatic index close to 7/4.

AB - Experiments conducted in the Alcator C-Mod tokamak have explored the physics of reversed shear Alfvén eigenmodes (RSAEs) during the current ramp. The frequency evolution of the RSAEs during the current ramp provides a constraint on the evolution of qmin, a result which is important in transport modeling and for comparison with other diagnostics which directly measure the magnetic field line structure. Additionally, a scaling of the RSAE minimum frequency with the sound speed is used to derive bounds on the adiabatic index, a measure of the plasma compressibility. This scaling places the adiabatic index at 1.40±0.15 and supports the kinetic calculation of separate electron and ion compressibilities with an ion adiabatic index close to 7/4.

UR - https://www.scopus.com/pages/publications/78650007301

UR - https://www.scopus.com/inward/citedby.url?scp=78650007301&partnerID=8YFLogxK

U2 - 10.1088/0741-3335/52/11/115003

DO - 10.1088/0741-3335/52/11/115003

M3 - Article

AN - SCOPUS:78650007301

SN - 0741-3335

VL - 52

JO - Plasma Physics and Controlled Fusion

JF - Plasma Physics and Controlled Fusion

IS - 11

M1 - 115003

ER -

Experimental study of reversed shear Alfvén eigenmodes during the current ramp in the Alcator C-Mod tokamak

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this