Simulation of driven flare-associated disturbances in the solar wind

Abstract

The dynamics of nonspherical flare-associated disturbances are considered when the outflow of energetic material at 0.1 AU, which gives rise to the disturbance, is maintained for an arbitrary period of time. The propagation of such disturbances into the interplanetary medium is examined under conditions of different total disturbance energies, energy flux densities, and sizes of the disturbance region at 0.1 AU. The development of these disturbances is followed by using numerical solutions of time dependent two-dimensional hydrodynamic flow in spherical coordinates. Decreasing the total disturbance energy by reducing its duration produces an increase in transit time to 1 AU, ranging from ~37 hours for Eioi= 2.9 x 1032 ergs to 58 hours for Etot= 2.8 x 1030 ergs, all for disturbances contained initially in a cone of a half angle equal to 15 deg . Variation of energy flux density at O.1 AU shows that disturbances of constant total energy propagate to 1 AU more slowly as the flux density at 0.1 AU decreases. Disturbances that differ only in the area that contains the outflow at 0.1 AU reflect this condition in the shock front shapes at larger heliocentric distances, smaller initial areas resulting in shock fronts with a smallermore » radius of curvature at 1 AU.« less