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Title: Observing Formation of Flux Rope by Tether-cutting Reconnection in the Sun

Abstract

Tether-cutting reconnection is considered as one mechanism for the formation of a flux rope. It has been proposed for more than 30 years; however, so far, direct observations of it are very rare. In this Letter, we present observations of the formation of a flux rope via tether-cutting reconnection in NOAA AR 11967 on 2014 February 2 by combining observations with the New Vacuum Solar Telescope and the Solar Dynamic Observatory . The tether-cutting reconnection occurs between two sets of highly sheared magnetic arcades. Comprehensive observational evidence of the reconnection is as follows: changes of the connections between the arcades, brightenings at the reconnection site, hot outflows, formation of a flux rope, slow-rise motion of the flux rope, and flux cancelation. The outflows are along three directions from the reconnection site to the footpoints with the velocities from 24 ± 1 km s{sup −1} to 69 ± 5 km s{sup −1}. Additionally, it is found that the newly formed flux rope connects far footpoints and has a left-handed twisted structure with many fine threads and a concave-up-shape structure in the middle. All the observations are in agreement with the tether-cutting model and provide evidence that tether-cutting reconnection leads to themore » formation of the flux rope associated with flux shear flow and cancelation.« less

Authors:
; ; ; ;  [1]
  1. Yunnan Observatories, Chinese Academy of Sciences, Kunming Yunnan 650216 (China)
Publication Date:
OSTI Identifier:
22654480
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 840; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHROMOSPHERE; MAGNETIC FIELDS; ROPES; SHEAR; SUN; TELESCOPES; VELOCITY

Citation Formats

Xue, Zhike, Yan, Xiaoli, Yang, Liheng, Wang, Jincheng, and Zhao, Li, E-mail: zkxue@ynao.ac.cn. Observing Formation of Flux Rope by Tether-cutting Reconnection in the Sun. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA7066.
Xue, Zhike, Yan, Xiaoli, Yang, Liheng, Wang, Jincheng, & Zhao, Li, E-mail: zkxue@ynao.ac.cn. Observing Formation of Flux Rope by Tether-cutting Reconnection in the Sun. United States. doi:10.3847/2041-8213/AA7066.
Xue, Zhike, Yan, Xiaoli, Yang, Liheng, Wang, Jincheng, and Zhao, Li, E-mail: zkxue@ynao.ac.cn. 2017. "Observing Formation of Flux Rope by Tether-cutting Reconnection in the Sun". United States. doi:10.3847/2041-8213/AA7066.
@article{osti_22654480,
title = {Observing Formation of Flux Rope by Tether-cutting Reconnection in the Sun},
author = {Xue, Zhike and Yan, Xiaoli and Yang, Liheng and Wang, Jincheng and Zhao, Li, E-mail: zkxue@ynao.ac.cn},
abstractNote = {Tether-cutting reconnection is considered as one mechanism for the formation of a flux rope. It has been proposed for more than 30 years; however, so far, direct observations of it are very rare. In this Letter, we present observations of the formation of a flux rope via tether-cutting reconnection in NOAA AR 11967 on 2014 February 2 by combining observations with the New Vacuum Solar Telescope and the Solar Dynamic Observatory . The tether-cutting reconnection occurs between two sets of highly sheared magnetic arcades. Comprehensive observational evidence of the reconnection is as follows: changes of the connections between the arcades, brightenings at the reconnection site, hot outflows, formation of a flux rope, slow-rise motion of the flux rope, and flux cancelation. The outflows are along three directions from the reconnection site to the footpoints with the velocities from 24 ± 1 km s{sup −1} to 69 ± 5 km s{sup −1}. Additionally, it is found that the newly formed flux rope connects far footpoints and has a left-handed twisted structure with many fine threads and a concave-up-shape structure in the middle. All the observations are in agreement with the tether-cutting model and provide evidence that tether-cutting reconnection leads to the formation of the flux rope associated with flux shear flow and cancelation.},
doi = {10.3847/2041-8213/AA7066},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 840,
place = {United States},
year = 2017,
month = 5
}
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