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Oblique Magnetohydrodynamic Cosmic-Ray-Modified Shocks: Two-Fluid Numerical Simulations

Published online by Cambridge University Press:  12 April 2016

Adam Frank
Affiliation:
Department of Astronomy, University of Minnesota, Minneapolis, MN 55455
T. W. Jones
Affiliation:
Department of Astronomy, University of Minnesota, Minneapolis, MN 55455
Dongsu Ryu
Affiliation:
Princeton University Observatory, Peyton Hall, Princeton, NJ 08544, and Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764, Korea

Abstract

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We present the first results of time-dependent two-fluid cosmic-ray (CR) modified MHD shock simulations. The calculations were carried out with a new numerical code for one-dimensional ideal MHD. By coupling this code with the CR energy transport equation we can simulate the time-dependent evolution of MHD shocks, including the acceleration of the CR and their feedback on the shock structures. We report tests of the combined numerical method including comparisons with analytical steady state results published earlier by Webb, as well as internal consistency checks for more general MHD CR shock structures after they appear to have converged to dynamical steady states. We also present results from an initial time-dependent simulation which extends the parameter space domain of previous analytical models. These new results support Webb’s suggestion that equilibrium oblique shocks are less effective than parallel shocks in the acceleration of CR. However, for realistic models of anisotropic CR diffusion, oblique shocks may achieve dynamical equilibrium on shorter timescales than parallel shocks.

Subject headings: cosmic rays — methods: numerical — MHD — shock waves

Type
Poster Papers
Copyright
Copyright © The American Astronomical Society 1994

References

Achterberg, A., Blandford, R.D., & Periwal, V. 1984, A&A, 98, 195 Google Scholar
Baring, M.G., Ellison, D.C., & Jones, F.C. 1993, ApJ, 409, 327 Google Scholar
Blandford, R.D., & Eichler, D. 1987, Phys Rept, 154, 1 Google Scholar
Drury, L.O’C., & Falle, S.A.E.G. 1986, MNRAS, 223, 353 Google Scholar
Drury, L.O’C., & VÖlk, H.J. 1981, ApJ, 248, 344 Google Scholar
Falle, S.A.E.G., & Giddings, J.R. 1987, MNRAS, 225, 399 Google Scholar
Harten, A. 1983, J. Comp. Phys., 49, 357 Google Scholar
Frank, A., Jones, T.W., & Ryu, D. 1994, in preparationGoogle Scholar
Jeffrey, A. 1966, Magnetohydrodynamics (London: Oliver & Boyd)Google Scholar
Jokipii, J.R. 1987, ApJ, 313, 846 Google Scholar
Jones, T.W., & Kang, H. 1990, ApJ, 363, 499 CrossRefGoogle Scholar
Kang, H., & Jones, T.W. 1990, ApJ, 353, 149 Google Scholar
Kang, H., & Jones, T.W. 1991, MNRAS, 249, 439 Google Scholar
Kang, H., Jones, T.W., & Ryu, D. 1992, ApJ, 385, 193 Google Scholar
Kennel, C.F., Edmiston, J.P., & Hada, T. 1985, in Collisionless Shocks in the Heliosphere: A Tutorial Review, ed. Robert G., Stone & Bruce, Tsurutani (Washington, DC: AGU), 1 Google Scholar
Ryu, D., & Jones, T.W. 1994, in preparationGoogle Scholar
Skilling, J. 1975, MNRAS, 172, 557 Google Scholar
Webb, G.M. 1983, A&A, 127, 97 Google Scholar
Webb, G.M. Drury, L.O’C., & Völk, H.J. 1986, A&A, 160, 335 Google Scholar
Zank, G.P., Axford, W.I., & McKenzie, J.F. 1990, A&A, 233, 275 Google Scholar