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arXiv · 1611.05033

Cusp-shaped structure of a jet observed by IRIS and SDO

Zhang Yuzong·Zhang Jun
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Abstract

On 29 August 2014, the trigger and evolution of a cusp-shaped jet were captured in detail at 1330 Å by the Interface Region Imaging Spectrograph.At first, two neighboring mini-prominences arose in turn from low solar atmosphere and collided with a loop-like system over them. The collisions between the loop-like system and the mini-prominences lead to the blowout and then a cusp-shaped jet formed with a spire and an arch-base. In the spire, many brightening blobs originating from the junction between the spire and the arch-base, moved upward in a rotating manner and then in a straight line in the late phase of the jet. In the arch-base, dark and bright material simultaneously tracked in a fan-like structure and the majority of the material moved along the fan's threads. At the later phase of the jet's evolution, bidirectional flows emptied the arch-base, while down-flows emptied the spire, thus making the jet entirely vanish. The extremely detailed observations in this study shed new light on how magnetic reconnection alters the inner topological structure of a jet, and provide a beneficial complement for understanding current jet models.

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Zhang Yuzong, Zhang Jun. 2016-11-15. Cusp-shaped structure of a jet observed by IRIS and SDO. https://doi.org/10.3847/1538-4357%2F834%2F1%2F79

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