Using HT and DT gamma rays to diagnose mix in Omega capsule implosions

doi:10.1088/1742-6596/717/1/012048

Title: Using HT and DT gamma rays to diagnose mix in Omega capsule implosions

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Abstract

Experimental evidence [1] indicates that shell material can be driven into the core of Omega capsule implosions on the same time scale as the initial convergent shock. It has been hypothesized that shock-generated temperatures at the fuel/shell interface in thin exploding pusher capsules diffusively drives shell material into the gas core between the time of shock passage and bang time. Here, we propose a method to temporally resolve and observe the evolution of shell material into the capsule core as a function of fuel/shell interface temperature (which can be varied by varying the capsule shell thickness). Our proposed method uses a CD plastic capsule filled with 50/50 HT gas and diagnosed using gas Cherenkov detection (GCD) to temporally resolve both the HT "clean" and DT "mix" gamma ray burn histories. Simulations using Hydra [2] for an Omega CD-lined capsule with a sub-micron layer of the inside surface of the shell pre-mixed into a fraction of the gas region produce gamma reaction history profiles that are sensitive to the depth to which this material is mixed. Furthermore, we observe these differences as a function of capsule shell thickness is proposed to determine if interface mixing is consistent with thermal diffusion λ_ii~T²/Z²ρmore »« less

Authors:: Schmitt, M. J.; Herrmann, H. W.; Kim, Y. H.; McEvoy, A. M.; Zylstra, A.; Hammel, B. A.; Sepke, S. M.; Leatherland, A.; Gales, S.

Publication Date:: 2016-05-26

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1335611

Report Number(s):: LA-UR-15-28239
Journal ID: ISSN 1742-6588

Grant/Contract Number:: AC52-06NA25396

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Physics. Conference Series

Additional Journal Information:: Journal Volume: 717; Journal ID: ISSN 1742-6588

Publisher:: IOP Publishing

Country of Publication:: United States

Language:: English

Subject:: 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; gamma rays; mix; implosions

Citation Formats


                    Schmitt, M. J., Herrmann, H. W., Kim, Y. H., McEvoy, A. M., Zylstra, A., Hammel, B. A., Sepke, S. M., Leatherland, A., and Gales, S. Using HT and DT gamma rays to diagnose mix in Omega capsule implosions.  United States: N. p., 2016. 
        Web.  doi:10.1088/1742-6596/717/1/012048.

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                    Schmitt, M. J., Herrmann, H. W., Kim, Y. H., McEvoy, A. M., Zylstra, A., Hammel, B. A., Sepke, S. M., Leatherland, A., & Gales, S. Using HT and DT gamma rays to diagnose mix in Omega capsule implosions.  United States.  doi:10.1088/1742-6596/717/1/012048.

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                    Schmitt, M. J., Herrmann, H. W., Kim, Y. H., McEvoy, A. M., Zylstra, A., Hammel, B. A., Sepke, S. M., Leatherland, A., and Gales, S. Thu .  
        "Using HT and DT gamma rays to diagnose mix in Omega capsule implosions".  United States.  doi:10.1088/1742-6596/717/1/012048.  https://www.osti.gov/servlets/purl/1335611.

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@article{osti_1335611,

  title        = {Using HT and DT gamma rays to diagnose mix in Omega capsule implosions},

  author       = {Schmitt, M. J. and Herrmann, H. W. and Kim, Y. H. and McEvoy, A. M. and Zylstra, A. and Hammel, B. A. and Sepke, S. M. and Leatherland, A. and Gales, S.},

  abstractNote = {Experimental evidence [1] indicates that shell material can be driven into the core of Omega capsule implosions on the same time scale as the initial convergent shock. It has been hypothesized that shock-generated temperatures at the fuel/shell interface in thin exploding pusher capsules diffusively drives shell material into the gas core between the time of shock passage and bang time. Here, we propose a method to temporally resolve and observe the evolution of shell material into the capsule core as a function of fuel/shell interface temperature (which can be varied by varying the capsule shell thickness). Our proposed method uses a CD plastic capsule filled with 50/50 HT gas and diagnosed using gas Cherenkov detection (GCD) to temporally resolve both the HT "clean" and DT "mix" gamma ray burn histories. Simulations using Hydra [2] for an Omega CD-lined capsule with a sub-micron layer of the inside surface of the shell pre-mixed into a fraction of the gas region produce gamma reaction history profiles that are sensitive to the depth to which this material is mixed. Furthermore, we observe these differences as a function of capsule shell thickness is proposed to determine if interface mixing is consistent with thermal diffusion λii~T2/Z2ρ at the gas/shell interface. Finally, since hydrodynamic mixing from shell perturbations, such as the mounting stalk and glue, could complicate these types of capsule-averaged temporal measurements, simulations including their effects also have been performed showing minimal perturbation of the hot spot geometry.},

  doi          = {10.1088/1742-6596/717/1/012048},

  journal      = {Journal of Physics. Conference Series},

  number       = ,

  volume       = 717,

  place        = {United States},

  year         = {2016},

  month        = {5}

}

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DOI: 10.1088/1742-6596/717/1/012048

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