Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas

Jacoby, B. A.; York, T. M.; Mollo, R. A.

doi:10.2172/6132813

Title: Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas

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Abstract

Conventional Thomson scattering using a ruby laser evidences difficulty in scattered signal detection as electron densities drop below 10/sup 13/ cm/sup -3/. Studies of plasmas of interest, such as theta-pinch endloss flow, can require density resolution in that range. Use of a Nd-Glass Laser as a source and frequency doubling the output can result in increases in the incident energy and quantum efficiency of the detectors such that gains in scattered signal of greater than an order of magnitude over a conventional ruby laser system can be achieved. Due to the approx. 25A bandwidth of the Nd-Glass Laser line, however, the electron temperature information in the incoherent scattered signal must be extracted from a Voight profile, not from the usual Gaussian profile as when a ruby laser is used.

Authors:: Jacoby, B. A.; York, T. M.; Mollo, R. A.

Publication Date:: 1979-02-01

Research Org.:: Pennsylvania State Univ., University Park, PA (United States)

OSTI Identifier:: 6132813

Report Number(s):: COO-4020-8
TRN: 79-010064

DOE Contract Number:: EY-76-S-02-4020

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; PLASMA DIAGNOSTICS; THOMSON SCATTERING; ELECTRON DENSITY; ELECTRON TEMPERATURE; NEODYMIUM LASERS; PLASMA DENSITY; INELASTIC SCATTERING; LASERS; SCATTERING; SOLID STATE LASERS; 700102* - Fusion Energy- Plasma Research- Diagnostics

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                    Jacoby, B. A., York, T. M., and Mollo, R. A.. Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas.  United States: N. p., 1979. 
        Web.  doi:10.2172/6132813.

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                    Jacoby, B. A., York, T. M., & Mollo, R. A.. Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas.  United States.  https://doi.org/10.2172/6132813

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                    Jacoby, B. A., York, T. M., and Mollo, R. A.. 1979.  
        "Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas".  United States.  https://doi.org/10.2172/6132813.  https://www.osti.gov/servlets/purl/6132813.

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@article{osti_6132813,

  title        = {Doubled Nd-glass laser system for incoherent Thomson scattering from low density plasmas},

  author       = {Jacoby, B. A. and York, T. M. and Mollo, R. A.},

  abstractNote = {Conventional Thomson scattering using a ruby laser evidences difficulty in scattered signal detection as electron densities drop below 10/sup 13/ cm/sup -3/. Studies of plasmas of interest, such as theta-pinch endloss flow, can require density resolution in that range. Use of a Nd-Glass Laser as a source and frequency doubling the output can result in increases in the incident energy and quantum efficiency of the detectors such that gains in scattered signal of greater than an order of magnitude over a conventional ruby laser system can be achieved. Due to the approx. 25A bandwidth of the Nd-Glass Laser line, however, the electron temperature information in the incoherent scattered signal must be extracted from a Voight profile, not from the usual Gaussian profile as when a ruby laser is used.},

  doi          = {10.2172/6132813},

  url          = {https://www.osti.gov/biblio/6132813},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1979},

  month        = {2}

}

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