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Randomization of a laser wave front by the turbulent gas-puff -pinch plasma column
Phys. Rev. E 111, 045202 – Published 8 April, 2025
DOI: https://doi.org/10.1103/PhysRevE.111.045202
Abstract
In this paper, we present the first direct experimental evidence supported by numerical modeling of a turbulent plasma column formed during a gas-puff -pinch implosion generated by the cobra current. Utilizing an imaging refractometer, we showed a significant decrease in spatial autocorrelation of the laser field and the appearance of a laser speckle pattern shortly before stagnation. The intensity distribution of the speckles measured during different shot campaigns while employing long and short cobra pulses follows the speckle statistics satisfactorily. The imaging refractometer signal is proportional to the integral over the electron density gradients; hence, the measured phase randomization of the individual plane waves composing the laser field implies a random density distribution. To validate this, the beam propagation method code simulates the laser beam propagation through different artificial density distributions with various average fluctuation scales and generates synthetic imaging refractometer data. The results reproduce similar trends in the experimental data, such as the increasing vertical width for the decreasing average spatial scale of the fluctuations and the decreasing spatial correlation length of the laser field. Therefore, during the gas-puff -pinch implosion process, it is likely that the plasma flow is almost always turbulent with the average spatial scale of the turbulent density fluctuations decreasing towards stagnation.
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References (23)
- R. P. Drake, E. C. Harding, and C. C. Kuranz, Approaches to turbulence in high-energy-density experiments, Phys. Scr. 2008, 014022 (2008).
- T. G. White, M. T. Oliver, P. Mabey, M. Kühn-Kauffeldt, A. F. A. Bott, L. N. K. Döhl, A. R. Bell, R. Bingham, R. Clarke, J. Foster, G. Giacinti, P. Graham, R. Heathcote, M. Koenig, Y. Kuramitsu, D. Q. Lamb, J. Meinecke, T. Michel, F. Miniati, M. Notley et al., Supersonic plasma turbulence in the laboratory, Nat. Commun. 10, 1758 (2019).
- G. W. Collins, J. C. Valenzuela, C. A. Speliotopoulos, N. Aybar, F. Conti, F. N. Beg, P. Tzeferacos, B. Khiar, A. F. A. Bott, and G. Gregori, Role of collisionality and radiative cooling in supersonic plasma jet collisions of different materials, Phys. Rev. E 101, 023205 (2020).
- O. A. Hurricane, V. A. Smalyuk, K. Raman, O. Schilling, J. F. Hansen, G. Langstaff, D. Martinez, H.-S. Park, B. A. Remington, H. F. Robey, J. A. Greenough, R. Wallace, C. A. Di Stefano, R. P. Drake, D. Marion, C. M. Krauland, and C. C. Kuranz, Validation of a turbulent Kelvin-Helmholtz shear layer model using a high-energy-density OMEGA laser experiment, Phys. Rev. Lett. 109, 155004 (2012).
- S. R. Nagel, K. S. Raman, C. M. Huntington, S. A. MacLaren, P. Wang, M. A. Barrios, T. Baumann, J. D. Bender, L. R. Benedetti, D. M. Doane, S. Felker, P. Fitzsimmons, K. A. Flippo, J. P. Holder, D. N. Kaczala, T. S. Perry, R. M. Seugling, L. Savage, and Y. Zhou, A platform for studying the Rayleigh–Taylor and Richtmyer–Meshkov instabilities in a planar geometry at high energy density at the National Ignition Facility, Phys. Plasmas 24, 072704 (2017).
- C. Weber, N. Haehn, J. Oakley, D. Rothamer, and R. Bonazza, Turbulent mixing measurements in the Richtmyer-Meshkov instability, Phys. Fluids 24, 074105 (2012).
- E. Kroupp, E. Stambulchik, A. Starobinets, D. Osin, V. I. Fisher, D. Alumot, Y. Maron, S. Davidovits, N. J. Fisch, and A. Fruchtman, Turbulent stagnation in a -pinch plasma, Phys. Rev. E 97, 013202 (2018).
- E. Kroupp, D. Osin, A. Starobinets, V. Fisher, V. Bernshtam, L. Weingarten, Y. Maron, I. Uschmann, E. Forster, A. Fisher, M. E. Cuneo, C. Deeney, and J. L. Giuliani, Ion temperature and hydrodynamic-energy measurements in a -pinch plasma at stagnation, Phys. Rev. Lett. 107, 105001 (2011).
- S. V. R. Rocco, E. S. Lavine, J. T. Banasek, W. M. Potter, and D. A. Hammer, Applying Thomson scattering to diagnosing turbulent density and velocity fluctuations in a gas-puff z-pinch, Phys. Plasmas 29, 110703 (2022).
- E. S. Lavine, S. V. R. Rocco, W. M. Potter, J. Angel, E. Freeman, J. T. Banasek, J. Lawson, J. B. Greenly, H. Wilhelm, D. A. Hammer, and B. R. Kusse, Measurements of the imploding plasma sheath in triple-nozzle gas-puff z pinches, Phys. Plasmas 29, 062702 (2022).
- J. D. Hare, G. C. Burdiak, S. Merlini, J. P. Chittenden, T. Clayson, A. J. Crilly, J. W. D. Halliday, D. R. Russell, R. A. Smith, N. Stuart, L. G. Suttle, and S. V. Lebedev, An imaging refractometer for density fluctuation measurements in high energy density plasmas, Rev. Sci. Instrum. 92, 033521 (2021).
- K. Okamoto, Fundamentals of Optical Waveguides (Academic, San Diego, 2006).
- J. B. Greenly, J. D. Douglas, D. A. Hammer, B. R. Kusse, S. C. Glidden, and H. D. Sanders, A 1MA, variable risetime pulse generator for high energy density plasma research, Rev. Sci. Instrum. 79, 073501 (2008).
- W. H. Press, B. P. Flannery, S. A. Teukolsky, and W. T. Vetterling, Numerical Recipes: The Art of Scientific Computing (Cambridge University, New York, 1986).
- J. Angel, Development of the Zeeman polarization spectroscopy system on Cobra, Ph.D. thesis, Cornell University, 2024.
- J. Timmer and M. Koenig, On generating power law noise, Astron. Astrophys. 300, 707 (1995).
- J. W. Goodman, Introduction to Fourier Optics (Roberts and Company, Englewood, CO, 2005).
- I. H. Hutchinson, Principles of Plasma Diagnostics (Cambridge University, Cambridge, England, 2002).
- A. Rososhek, B. R. Kusse, W. M. Potter, N. J. Wilson, E. S. Lavine, and D. A. Hammer, Wavenumber calibration for an imaging refractometer, arXiv:2408.02660.
- A. Labeyrie, Attainment of diffraction limited resolution in large telescopes by Fourier analysing speckle patterns in star images, Astron. Astrophys. 6, 85 (1970).
- J. W. Goodman, Statistical Properties of Laser Speckle Patterns, in Laser Speckle and Related Phenomena, edited by J. C. Dainty (Springer, Berlin, 1975), pp. 9–75.
- G. van Soest, F. J. Poelwijk, and A. Lagendijk, Speckle experiments in random lasers, Phys. Rev. E 65, 046603 (2002).
- T. Stewart McKechnie, General Theory of Light Propagation and Imaging through the Atmosphere (Springer, Berlin, 2016).