Effect of shock normal orientation fluctuations on field-aligned beam distributions

K. Meziane, A. M. Hamza, M. Wilber, M. A. Lee, C. Mazelle, E. A. Lucek, Tohru Hada, A. Markowitch

    研究成果: ジャーナルへの寄稿Conference article

    2 引用 (Scopus)

    抄録

    We address the unsolved question of how foreshock field-aligned beam (FAB) parallel temperatures are produced. Studies including numerical simulations and recent observations have indicated that shocks can be nonstationary and include embedded spatial structures with varied scales. As a first step towards assessing the impact of such variability on backstreaming ions, we examine how a randomly distributed shock normal direction will affect FAB parallel velocity (v||) distributions. Assuming that the FABs are produced in a quasi-adiabatic reflection process at the shock, we derive a probability distribution function for v||. These derived distributions exhibit second, third and fourth order moments that agree well with the observations for a large range of reflection efficiencies δ, and depend strongly upon the average angle between the magnetic field and the shock normal θBn0. Best agreement is obtained for fluctuations of the normal orientation of a few degrees about a nominal direction. The derived model predicts a strong correlation between the shock geometry (θBn0) and the moments of the parallel velocity distribution, but with stronger tails extending to higher values of θBn0, a trend opposite to the observations.

    元の言語英語
    ページ(範囲)349-362
    ページ数14
    ジャーナルAstrophysics and Space Science Proceedings
    発行部数202469
    DOI
    出版物ステータス出版済み - 1 1 2010
    イベント15th Workshop on Cluster Active Archive, 2008 - Tenerife, Canary Islands, スペイン
    継続期間: 3 9 20083 15 2008

    Fingerprint

    Velocity distribution
    shock
    Probability distributions
    Distribution functions
    Ions
    Magnetic fields
    velocity distribution
    foreshock
    Geometry
    Computer simulation
    moments
    FORTRAN
    probability distribution functions
    magnetic field
    geometry
    Temperature
    Direction compound
    distribution
    effect
    ion

    All Science Journal Classification (ASJC) codes

    • Physics and Astronomy(all)
    • Computer Science Applications
    • Spectroscopy
    • Space and Planetary Science
    • Nuclear and High Energy Physics

    これを引用

    Meziane, K., Hamza, A. M., Wilber, M., Lee, M. A., Mazelle, C., Lucek, E. A., ... Markowitch, A. (2010). Effect of shock normal orientation fluctuations on field-aligned beam distributions. Astrophysics and Space Science Proceedings, (202469), 349-362. https://doi.org/10.1007/978-90-481-3499-1_23

    Effect of shock normal orientation fluctuations on field-aligned beam distributions. / Meziane, K.; Hamza, A. M.; Wilber, M.; Lee, M. A.; Mazelle, C.; Lucek, E. A.; Hada, Tohru; Markowitch, A.

    :: Astrophysics and Space Science Proceedings, 番号 202469, 01.01.2010, p. 349-362.

    研究成果: ジャーナルへの寄稿Conference article

    Meziane, K, Hamza, AM, Wilber, M, Lee, MA, Mazelle, C, Lucek, EA, Hada, T & Markowitch, A 2010, 'Effect of shock normal orientation fluctuations on field-aligned beam distributions', Astrophysics and Space Science Proceedings, 番号 202469, pp. 349-362. https://doi.org/10.1007/978-90-481-3499-1_23
    Meziane, K. ; Hamza, A. M. ; Wilber, M. ; Lee, M. A. ; Mazelle, C. ; Lucek, E. A. ; Hada, Tohru ; Markowitch, A. / Effect of shock normal orientation fluctuations on field-aligned beam distributions. :: Astrophysics and Space Science Proceedings. 2010 ; 番号 202469. pp. 349-362.
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    AU - Wilber, M.

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    AU - Mazelle, C.

    AU - Lucek, E. A.

    AU - Hada, Tohru

    AU - Markowitch, A.

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