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arXiv · 1002.3792

Microflare Activity driven by Forced Magnetic Reconnection

D. B. Jess·M. Mathioudakis·P. K. Browning·P. J. Crockett·F. P. Keenan
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Abstract

High cadence, multiwavelength, optical observations of a solar active region are presented, obtained with the Swedish Solar Telescope. Two magnetic bright points are seen to separate in opposite directions at a constant velocity of 2.8km/s. After a separation distance of approximately 4400km is reached, multiple Ellerman bombs are observed in both H-alpha and Ca-K images. As a result of the Ellerman bombs, periodic velocity perturbations in the vicinity of the magnetic neutral line, derived from simultaneous MDI data, are generated with amplitude +/- 6km/s and wavelength 1000km. The velocity oscillations are followed by an impulsive brightening visible in H-alpha and Ca-K, with a peak intensity enhancement of 63%. We interpret these velocity perturbations as the magnetic field deformation necessary to trigger forced reconnection. A time delay of approximately 3min between the H-alpha wing and Ca-K observations indicate that the observed magnetic reconnection occurs at a height of 200km above the solar surface. These observations are consistent with theoretical predictions and provide the first observational evidence of microflare activity driven by forced magnetic reconnection.

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D. B. Jess, M. Mathioudakis, P. K. Browning, P. J. Crockett, F. P. Keenan. 2010-02-19. Microflare Activity driven by Forced Magnetic Reconnection. https://doi.org/10.1088/2041-8205%2F712%2F1%2Fl111

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