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arXiv · 1107.3113

Kink waves in an active region dynamic fibril

A. Pietarila·R. Aznar Cuadrado·J. Hirzberger·S. K. Solanki
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Abstract

We present high spatial and temporal resolution Ca II 8542 observations of a kink wave in an on-disk chromospheric active region fibril. The properties of the wave are similar to those observed in off-limb spicules. From the observed phase and period of the wave we determine a lower limit for the field strength in the chromospheric active region fibril located at the edge of a sunspot to be a few hundred Gauss. We find indications that the event was triggered by a small-scale reconnection event higher up in the atmosphere.

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A. Pietarila, R. Aznar Cuadrado, J. Hirzberger, S. K. Solanki. 2011-07-15. Kink waves in an active region dynamic fibril. https://doi.org/10.1088/0004-637x/739/2/92

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