TY - JOUR
T1 - Motional Stark Effect measurements of the local magnetic field in high temperature fusion plasmas
AU - Wolf, R. C.
AU - Bock, A.
AU - Ford, O. P.
AU - Reimer, R.
AU - Burckhart, A.
AU - Dinklage, A.
AU - Hobirk, J.
AU - Howard, J.
AU - Reich, M.
AU - Stober, J.
N1 - Publisher Copyright:
© 2015 Max Planck Institute for Plasma Physics.
PY - 2015/10/8
Y1 - 2015/10/8
N2 - The utilization of the Motional Stark Effect (MSE) experienced by the neutral hydrogen or deuterium injected into magnetically confined high temperature plasmas is a well established technique to infer the internal magnetic field distribution of fusion experiments. In their rest frame, the neutral atoms experience a Lorentz electric field, EL = v × B, which results in a characteristic line splitting and polarized line emission. The different properties of the Stark multiplet allow inferring, both the magnetic field strength and the orientation of the magnetic field vector. Besides recording the full MSE spectrum, several types of polarimeters have been developed to measure the polarization direction of the Stark line emission. To test physics models of the magnetic field distribution and dynamics, the accuracy requirements are quite demanding. In view of these requirements, the capabilities and issues of the different techniques are discussed, including the influence of the Zeeman Effect and the sensitivity to radial electric fields. A newly developed Imaging MSE system, which has been tested on the ASDEX Upgrade tokamak, is presented. The sensitivity allows to resolve sawtooth oscillations.
AB - The utilization of the Motional Stark Effect (MSE) experienced by the neutral hydrogen or deuterium injected into magnetically confined high temperature plasmas is a well established technique to infer the internal magnetic field distribution of fusion experiments. In their rest frame, the neutral atoms experience a Lorentz electric field, EL = v × B, which results in a characteristic line splitting and polarized line emission. The different properties of the Stark multiplet allow inferring, both the magnetic field strength and the orientation of the magnetic field vector. Besides recording the full MSE spectrum, several types of polarimeters have been developed to measure the polarization direction of the Stark line emission. To test physics models of the magnetic field distribution and dynamics, the accuracy requirements are quite demanding. In view of these requirements, the capabilities and issues of the different techniques are discussed, including the influence of the Zeeman Effect and the sensitivity to radial electric fields. A newly developed Imaging MSE system, which has been tested on the ASDEX Upgrade tokamak, is presented. The sensitivity allows to resolve sawtooth oscillations.
KW - Nuclear instruments and methods for hot plasma diagnostics
KW - Plasma diagnostics - interferometry, spectroscopy and imaging
UR - http://www.scopus.com/inward/record.url?scp=84947080673&partnerID=8YFLogxK
U2 - 10.1088/1748-0221/10/10/P10008
DO - 10.1088/1748-0221/10/10/P10008
M3 - Article
SN - 1748-0221
VL - 10
JO - Journal of Instrumentation
JF - Journal of Instrumentation
IS - 10
M1 - P10008
ER -