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Title: Rotating Magnetic Structures Associated with a Quasi-circular Ribbon Flare

Abstract

We present the detection of a small eruption and the associated quasi-circular ribbon flare during the emergence of a bipole occurring on 2015 February 3. Under a fan dome, a sigmoid was rooted in a single magnetic bipole, which was encircled by negative polarity. The nonlinear force-free field extrapolation shows the presence of twisted field lines, which can represent a sigmoid structure. The rotation of the magnetic bipole may cause the twisting of magnetic field lines. An initial brightening appeared at one of the footpoints of the sigmoid, where the positive polarity slides toward a nearby negative polarity field region. The sigmoid displayed an ascending motion and then interacted intensively with the spine-like field. This type of null point reconnection in corona led to a violent blowout jet, and a quasi-circular flare ribbon was also produced. The magnetic emergence and rotational motion are the main contributors to the energy buildup for the flare, while the cancellation and collision might act as a trigger.

Authors:
; ; ; ; ; ;  [1]
  1. Yunnan Observatories, Chinese Academy of Sciences, 396 Yangfangwang, Guandu District, Kunming, 650216 (China)
Publication Date:
OSTI Identifier:
22663747
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; 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; BLOWOUTS; COLLISIONS; DETECTION; EXTRAPOLATION; MAGNETIC FIELDS; NONLINEAR PROBLEMS; ROTATION; STELLAR FLARES; SUN

Citation Formats

Li, Haidong, Jiang, Yunchun, Yang, Jiayan, Yang, Bo, Xu, Zhe, Hong, Junchao, and Bi, Yi, E-mail: lhd@ynao.ac.cn. Rotating Magnetic Structures Associated with a Quasi-circular Ribbon Flare. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA5EAC.
Li, Haidong, Jiang, Yunchun, Yang, Jiayan, Yang, Bo, Xu, Zhe, Hong, Junchao, & Bi, Yi, E-mail: lhd@ynao.ac.cn. Rotating Magnetic Structures Associated with a Quasi-circular Ribbon Flare. United States. doi:10.3847/1538-4357/AA5EAC.
Li, Haidong, Jiang, Yunchun, Yang, Jiayan, Yang, Bo, Xu, Zhe, Hong, Junchao, and Bi, Yi, E-mail: lhd@ynao.ac.cn. Mon . "Rotating Magnetic Structures Associated with a Quasi-circular Ribbon Flare". United States. doi:10.3847/1538-4357/AA5EAC.
@article{osti_22663747,
title = {Rotating Magnetic Structures Associated with a Quasi-circular Ribbon Flare},
author = {Li, Haidong and Jiang, Yunchun and Yang, Jiayan and Yang, Bo and Xu, Zhe and Hong, Junchao and Bi, Yi, E-mail: lhd@ynao.ac.cn},
abstractNote = {We present the detection of a small eruption and the associated quasi-circular ribbon flare during the emergence of a bipole occurring on 2015 February 3. Under a fan dome, a sigmoid was rooted in a single magnetic bipole, which was encircled by negative polarity. The nonlinear force-free field extrapolation shows the presence of twisted field lines, which can represent a sigmoid structure. The rotation of the magnetic bipole may cause the twisting of magnetic field lines. An initial brightening appeared at one of the footpoints of the sigmoid, where the positive polarity slides toward a nearby negative polarity field region. The sigmoid displayed an ascending motion and then interacted intensively with the spine-like field. This type of null point reconnection in corona led to a violent blowout jet, and a quasi-circular flare ribbon was also produced. The magnetic emergence and rotational motion are the main contributors to the energy buildup for the flare, while the cancellation and collision might act as a trigger.},
doi = {10.3847/1538-4357/AA5EAC},
journal = {Astrophysical Journal},
number = 2,
volume = 836,
place = {United States},
year = {Mon Feb 20 00:00:00 EST 2017},
month = {Mon Feb 20 00:00:00 EST 2017}
}
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