1997/07/31 by Paul A. Kimoto, David F. Chernoff
Engineering · Physics and Astronomy · #Astrophysics and Star Formation Studies #Computational Fluid Dynamics and Aerodynamics #Fluid Dynamics and Turbulent Flows #astro-ph
paper · pdf · doi:10.1086/304628
11 text pages, LaTeX/AASTeX (aaspp4); 5 figures; accepted by ApJ
arxiv created 1997/07/31 · openalex publication_date 1997/10/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
We discuss high-resolution simulations of one-dimensional, plane-parallel shock waves with mean speeds of between 150 and 240 km s -1 propagating into gas with Alfvén velocities of up to 40 km s -1 and outline the conditions under which these radiative shocks experience an oscillatory instability in the cooling length, the shock velocity, and the position of the shock front. We investigate two forms of postshock cooling: a truncated single power law and a more realistic piecewise power law. The degree of nonlinearity of the instability depends strongly on the cooling power law and the Alfvén Mach number: for power-law indices α < 0, typical magnetic field strengths may be insufficient either for stabilizing the fundamental oscillatory mode or for preventing the oscillations from reaching nonlinear amplitudes.