Analysis of MHD Interstellar Turbulence using Tsallis Statistics

Type Conference Paper
Names Benjamin M. Tofflemire, A. Lazarian, B. Burkhart
Proceedings Title Bulletin of the American Astronomical Society
Conference Name American Astronomical Society, AAS Meeting #217, #251.02
Volume 43
Pages 25102
Date January 1, 2011
Library Catalog NASA ADS
Abstract In an effort to characterize interstellar magneto-hydrodynamic (MHD) turbulence, we study probability distribution functions (PDFs) of spacial increments of density, velocity, and magnetic field strength for fourteen three dimensional ideal isothermal MHD simulations. We fit the PDFs using the Tsallis function and study the fit parameters dependence on the compressibility and magnetization of the gas. For three dimensional density, column density, and PPV (Position-Positions-Velocity) data we find that the Tsallis function fits PDFs of high resolution MHD turbulence well, with the fit parameters corresponding to amplitude and width showing strong sensitivities to the sonic and Alfvén Mach numbers. Specifically, the width of the PDF is sensitive to magnetization especially in cases where the sonic number is high. These dependencies are also found for cases where smoothing, noise, and cloud-like boundary conditions are introduced to simulate observable qualities. This could make Tsallis statistics a useful tool in characterizing magnetic fields in the interstellar medium. This work was supported by the National Science Foundation's REU program through NSF Award AST-1004881.
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