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arXiv · 1508.00672

Evolution and Dynamics of a Solar Active Prominence

Abstract

The life of a solar active prominence, one of the most remarkable objects on the Sun, is full of dynamics; after first appearing on the Sun the prominence continuously evolves with various internal motions and eventually produces a global eruption toward the interplane- tary space. Here we report that the whole life of an active prominence is successfully re- produced by performing as long-term a magnetohydrodynamic simulation of a magnetized prominence plasma as was ever done. The simulation reveals underlying dynamic processes that give rise to observed properties of an active prominence: invisible subsurface flows self- consistently produce the cancellation of magnetic flux observed at the photosphere, while observed and somewhat counterintuitive strong upflows are driven against gravity by en- hanced gas pressure gradient force along a magnetic field line locally standing vertical. The most highlighted dynamic event, transition into an eruptive phase, occurs as a natural con- sequence of the self-consistent evolution of a prominence plasma interacting with a magnetic field, which is obtained by seamlessly reproducing dynamic processes involved in the forma- tion and eruption of an active prominence.

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Tetsuya Magara. 2015-08-04. Evolution and Dynamics of a Solar Active Prominence. https://doi.org/10.1093/pasj%2Fpsv078

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