Models comparison for JET polarimeter data

Mazzotta, C; Orsitto, F P; Giovannozzi, E; Boboc, A; Tudisco, O; Zabeo, L; Brombin, M; Murari, A

doi:10.1063/1.2905056

Title: Models comparison for JET polarimeter data

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Abstract

A complete comparison between the theory and the measurements in polarimetry was done by using the Far Infrared Polarimeter at JET. More than 300 shots were analyzed, including a wide spectrum of JET scenarios in all critical conditions for polarimetry: high density, high and very low fields, high temperatures.This work is aimed at the demonstration of the robustness of the theoretical models for the JET polarimeter measurements in the perspective of using these models for ITER like plasma scenarios . In this context, an assessment was performed on how the line-integrated plasma density along the central vertical chord of FIR polarimeter could be evaluated using the Cotton-Mouton effect and its possible concrete use to correct fringe jumps of the interferometer.The models considered are: i) the rigorous numerical solution of the Stokes propagation equations, using dielectric tensor evaluated from JET equilibrium and Thomson scattering [1,2]; ii) two types of approximated solutions [2,3] and iii) the Guenther empirical model [4] that considers the mutual effect between Cotton-Mouton and Faraday rotation angle. The model calculations have been compared with polarimeter measurements for the Cotton-Mouton phase shift.The agreement with theory is satisfactory within the limits of experimental errors [3].

Authors:

Mazzotta, C; Orsitto, F P; Giovannozzi, E ^[1]; Boboc, A; Tudisco, O; Zabeo, L ^[2]; Brombin, M; Murari, A ^[3]

Centro Ricerche Energia Frascati, Euratom-ENEA Association, Frascati (Italy)
Association EURATOM-UKAEA Culham Science Centre Abingdon 0X14 3DB (UK) (United Kingdom)
Consorzio RFX, Euratom-ENEA Association, Padova (Italy)

Publication Date:: Wed Mar 12 00:00:00 EDT 2008

OSTI Identifier:: 21136757

Resource Type:: Journal Article

Journal Name:: AIP Conference Proceedings

Additional Journal Information:: Journal Volume: 988; Journal Issue: 1; Conference: International conference on burning plasma diagnostics, Varenna (Italy), 24-28 Sep 2007; Other Information: DOI: 10.1063/1.2905056; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA). EFDA-JET Contributors; Journal ID: ISSN 0094-243X

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPARATIVE EVALUATIONS; DIELECTRIC TENSOR; FARADAY EFFECT; INTERFEROMETERS; ITER TOKAMAK; JET TOKAMAK; NUMERICAL SOLUTION; PHASE SHIFT; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; POLARIMETERS; POLARIMETRY; THOMSON SCATTERING; VOIGT EFFECT

Citation Formats


                    Mazzotta, C, Orsitto, F P, Giovannozzi, E, Boboc, A, Tudisco, O, Zabeo, L, Brombin, M, and Murari, A. Models comparison for JET polarimeter data.  United States: N. p., 2008. 
        Web.  doi:10.1063/1.2905056.

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                    Mazzotta, C, Orsitto, F P, Giovannozzi, E, Boboc, A, Tudisco, O, Zabeo, L, Brombin, M, & Murari, A. Models comparison for JET polarimeter data.  United States.  https://doi.org/10.1063/1.2905056

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                    Mazzotta, C, Orsitto, F P, Giovannozzi, E, Boboc, A, Tudisco, O, Zabeo, L, Brombin, M, and Murari, A. 2008.  
        "Models comparison for JET polarimeter data".  United States.  https://doi.org/10.1063/1.2905056.

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@article{osti_21136757,

  title        = {Models comparison for JET polarimeter data},

  author       = {Mazzotta, C and Orsitto, F P and Giovannozzi, E and Boboc, A and Tudisco, O and Zabeo, L and Brombin, M and Murari, A},

  abstractNote = {A complete comparison between the theory and the measurements in polarimetry was done by using the Far Infrared Polarimeter at JET. More than 300 shots were analyzed, including a wide spectrum of JET scenarios in all critical conditions for polarimetry: high density, high and very low fields, high temperatures.This work is aimed at the demonstration of the robustness of the theoretical models for the JET polarimeter measurements in the perspective of using these models for ITER like plasma scenarios . In this context, an assessment was performed on how the line-integrated plasma density along the central vertical chord of FIR polarimeter could be evaluated using the Cotton-Mouton effect and its possible concrete use to correct fringe jumps of the interferometer.The models considered are: i) the rigorous numerical solution of the Stokes propagation equations, using dielectric tensor evaluated from JET equilibrium and Thomson scattering [1,2]; ii) two types of approximated solutions [2,3] and iii) the Guenther empirical model [4] that considers the mutual effect between Cotton-Mouton and Faraday rotation angle. The model calculations have been compared with polarimeter measurements for the Cotton-Mouton phase shift.The agreement with theory is satisfactory within the limits of experimental errors [3].},

  doi          = {10.1063/1.2905056},

  url          = {https://www.osti.gov/biblio/21136757},
  journal      = {AIP Conference Proceedings},

  issn         = {0094-243X},

  number       = 1,

  volume       = 988,

  place        = {United States},

  year         = {Wed Mar 12 00:00:00 EDT 2008},

  month        = {Wed Mar 12 00:00:00 EDT 2008}

}

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