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arXiv · 1012.0661

Numerical Simulations of Chromospheric Microflares

R. L. Jiang·C. Fang·P. F. Chen
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Abstract

With gravity, ionization, and radiation being considered, we perform 2.5D compressible resistive MHD simulations of chromospheric magnetic reconnection using the CIP-MOCCT scheme. The temperature distribution of the quiet-Sun atmospheric model VALC and the helium abundance (10%) are adopted. Our 2.5D MHD simulation reproduces qualitatively the temperature enhancement observed in chromospheric microflares. The temperature enhancement $ΔT$ is demonstrated to be sensitive to the background magnetic field, whereas the total evolution time $Δt$ is sensitive to the magnitude of the anomalous resistivity. Moveover, we found a scaling law, which is described as $ΔT/Δt \sim {n_H}^{-1.5} B^{2.1} {η_0}^{0.88}$. Our results also indicate that the velocity of the upward jet is much greater than that of the downward jet and the X-point may move up or down.

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R. L. Jiang, C. Fang, P. F. Chen. 2010-12-03. Numerical Simulations of Chromospheric Microflares. https://doi.org/10.1088/0004-637x%2F710%2F2%2F1387

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