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Title: Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets

Abstract

We investigate the formations and evolutions of two successive solar tornadoes in/near AR 12297 during 2015 March 19–20. Recurrent EUV jets close to two filaments were detected along a large-scale coronal loop prior to the appearances of the tornadoes. Under the disturbances from the activities, the filaments continually ascended and finally interacted with the loops tracked by the jets. Subsequently, the structures of the filaments and the loop were merged together, probably via magnetic reconnections, and formed tornado-like structures with a long spiral arm. Our observations suggest that solar tornadoes can be triggered by the interaction between filaments and nearby coronal jets, which has rarely been reported before. At the earlier development phase of the first tornado, about 30 small-scale sub-jets appeared in the tornado’s arm, accompanied by local EUV brightenings. They have an ejection direction approximately vertical to the axis of the arm and a typical maximum speed of ∼280 km s{sup −1}. During the ruinations of the two tornadoes, fast plasma outflows from the strong EUV brightenings inside tornadoes are observed, in company with the untangling or unwinding of the highly twisted tornado structures. These observational features indicate that self reconnections probably occurred between the tangled magnetic fieldsmore » of the tornadoes and resulted in the rapid disintegrations and disappearances of the tornadoes. According to the reconnection theory, we also derive the field strength of the tornado core to be ∼8 G.« less

Authors:
; ;  [1];  [2];  [3]
  1. Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
  2. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
  3. Key Laboratory for Dark Matter and Space Science, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)
Publication Date:
OSTI Identifier:
22654468
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 841; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; DISTURBANCES; EXTREME ULTRAVIOLET RADIATION; FILAMENTS; INTERACTIONS; MAGNETIC FIELDS; MAGNETIC RECONNECTION; PARTICLE TRACKS; PLASMA; ROTATION; SOLAR FLARES; SUN; TORNADOES

Citation Formats

Chen, Huadong, Zhang, Jun, Ma, Suli, Yan, Xiaoli, and Xue, Jianchao, E-mail: hdchen@nao.cas.cn, E-mail: zjun@nao.cas.cn. Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA71A2.
Chen, Huadong, Zhang, Jun, Ma, Suli, Yan, Xiaoli, & Xue, Jianchao, E-mail: hdchen@nao.cas.cn, E-mail: zjun@nao.cas.cn. Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets. United States. doi:10.3847/2041-8213/AA71A2.
Chen, Huadong, Zhang, Jun, Ma, Suli, Yan, Xiaoli, and Xue, Jianchao, E-mail: hdchen@nao.cas.cn, E-mail: zjun@nao.cas.cn. 2017. "Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets". United States. doi:10.3847/2041-8213/AA71A2.
@article{osti_22654468,
title = {Solar Tornadoes Triggered by Interaction between Filaments and EUV Jets},
author = {Chen, Huadong and Zhang, Jun and Ma, Suli and Yan, Xiaoli and Xue, Jianchao, E-mail: hdchen@nao.cas.cn, E-mail: zjun@nao.cas.cn},
abstractNote = {We investigate the formations and evolutions of two successive solar tornadoes in/near AR 12297 during 2015 March 19–20. Recurrent EUV jets close to two filaments were detected along a large-scale coronal loop prior to the appearances of the tornadoes. Under the disturbances from the activities, the filaments continually ascended and finally interacted with the loops tracked by the jets. Subsequently, the structures of the filaments and the loop were merged together, probably via magnetic reconnections, and formed tornado-like structures with a long spiral arm. Our observations suggest that solar tornadoes can be triggered by the interaction between filaments and nearby coronal jets, which has rarely been reported before. At the earlier development phase of the first tornado, about 30 small-scale sub-jets appeared in the tornado’s arm, accompanied by local EUV brightenings. They have an ejection direction approximately vertical to the axis of the arm and a typical maximum speed of ∼280 km s{sup −1}. During the ruinations of the two tornadoes, fast plasma outflows from the strong EUV brightenings inside tornadoes are observed, in company with the untangling or unwinding of the highly twisted tornado structures. These observational features indicate that self reconnections probably occurred between the tangled magnetic fields of the tornadoes and resulted in the rapid disintegrations and disappearances of the tornadoes. According to the reconnection theory, we also derive the field strength of the tornado core to be ∼8 G.},
doi = {10.3847/2041-8213/AA71A2},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 841,
place = {United States},
year = 2017,
month = 5
}
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