Hydrodynamic simulations of flare/surge events

✍ Scribed by R. S. Steinolfson; E. J. Schmahl; S. T. Wu

• Book ID: 104646685
• Publisher: Springer
• Year: 1979
• Tongue: English
• Weight: 706 KB
• Volume: 63
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00155709

✦ Synopsis

A one-dimensional, hydrodynamic, time-dependent model has been developed which simulates the major observed dynamics of flare associated surges. In particular, the thermodynamics, the surge mass, the time scales, the physical dimensions and the velocities of typical surge events are reproduced. The surge is created by a sudden increase in pressure at the top of the chromosphere. This pressure pulse produces a disturbance which is followed, with a time-dependent numerical solution, as it propagates upward through the transition region and into the corona. The leading edge of the disturbance is a weak shock which has only a slight effect on the original transition region and coronal thermodynamics. The major effect occurs in a region behind the shock where the temperature is decreased and the density is increased. This cool, dense region (the simulated surge event) moves upward initially and then begins falling back downward. After the material begins returning to the chromosphere, a second shock is formed in the chromosphere which propagates upward, brings the infalling material to rest and returns the atmosphere to hydrostatic equilibrium.