Laser induced fluorescence measurements of ion velocity and temperature of drift turbulence driven sheared plasma flow in a linear helicon plasma device

Using laser induced fluorescence (LIF), radial profiles of azimuthal ion fluid velocity and ion temperature are measured in the controlled shear de-correlation experiment (CSDX) linear helicon plasma device. Ion velocities and temperatures are derived from the measured Doppler broadened velocity dis...

Full description

Saved in:
Bibliographic Details
Published in:Physics of plasmas 2012-08, Vol.19 (8)
Main Authors: Chakraborty Thakur, S., McCarren, D., Lee, T., Fedorczak, N., Manz, P., Scime, E. E., Tynan, G. R., Xu, M.
Format: Article
Language:English
Subjects:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ARGON IONS
DISTRIBUTION FUNCTIONS
FLUID FLOW
FLUORESCENCE
ION TEMPERATURE
LASER-PRODUCED PLASMA
MAGNETIC FIELDS
MHZ RANGE
PLASMA DRIFT
PROBES
SHEAR
TIME DELAY
TURBULENCE
VELOCITY
WAVE PROPAGATION
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Using laser induced fluorescence (LIF), radial profiles of azimuthal ion fluid velocity and ion temperature are measured in the controlled shear de-correlation experiment (CSDX) linear helicon plasma device. Ion velocities and temperatures are derived from the measured Doppler broadened velocity distribution functions of argon ions. The LIF system employs a portable, high power (>300 mW), narrowband (∼1 MHz) tunable diode laser-based system operating at 668.614 nm. Previous studies in CSDX have shown the existence of a radially sheared azimuthal flow as measured with time delay estimation methods and Mach probes. Here, we report the first LIF measurements of sheared plasma fluid flow in CSDX. Above a critical magnetic field, the ion fluid flow profile evolves from radially uniform to peaked on axis with a distinct reversed flow region at the boundary, indicating the development of a sheared azimuthal flow. Simultaneously, the ion temperature also evolves from a radially uniform profile to a profile with a gradient. Measurements in turbulent and coherent drift wave mode dominated plasmas are compared.
ISSN:1070-664X
1089-7674
DOI:10.1063/1.4742178