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Title: Influence of Photospheric Magnetic Conditions on the Catastrophic Behaviors of Flux Ropes in Solar Active Regions

Abstract

Since only the magnetic conditions at the photosphere can be routinely observed in current observations, it is of great significance to determine the influences of photospheric magnetic conditions on solar eruptive activities. Previous studies about catastrophe indicated that the magnetic system consisting of a flux rope in a partially open bipolar field is subject to catastrophe, but not if the bipolar field is completely closed under the same specified photospheric conditions. In order to investigate the influence of the photospheric magnetic conditions on the catastrophic behavior of this system, we expand upon the 2.5-dimensional ideal magnetohydrodynamic model in Cartesian coordinates to simulate the evolution of the equilibrium states of the system under different photospheric flux distributions. Our simulation results reveal that a catastrophe occurs only when the photospheric flux is not concentrated too much toward the polarity inversion line and the source regions of the bipolar field are not too weak; otherwise no catastrophe occurs. As a result, under certain photospheric conditions, a catastrophe could take place in a completely closed configuration, whereas it ceases to exist in a partially open configuration. This indicates that whether the background field is completely closed or partially open is not the only necessarymore » condition for the existence of catastrophe, and that the photospheric conditions also play a crucial role in the catastrophic behavior of the flux rope system.« less

Authors:
; ; ; ;  [1]
  1. CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei 230026 (China)
Publication Date:
OSTI Identifier:
22663922
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; 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; CARTESIAN COORDINATES; CLOSED CONFIGURATIONS; DISTRIBUTION; EQUILIBRIUM; EVOLUTION; MAGNETIC FIELDS; MAGNETIC PROPERTIES; MAGNETOHYDRODYNAMICS; MASS; OPEN CONFIGURATIONS; PHOTOSPHERE; SIMULATION; SUN

Citation Formats

Zhang, Quanhao, Wang, Yuming, Hu, Youqiu, Liu, Rui, and Liu, Jiajia, E-mail: zhangqh@mail.ustc.edu.cn. Influence of Photospheric Magnetic Conditions on the Catastrophic Behaviors of Flux Ropes in Solar Active Regions. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/2/211.
Zhang, Quanhao, Wang, Yuming, Hu, Youqiu, Liu, Rui, & Liu, Jiajia, E-mail: zhangqh@mail.ustc.edu.cn. Influence of Photospheric Magnetic Conditions on the Catastrophic Behaviors of Flux Ropes in Solar Active Regions. United States. doi:10.3847/1538-4357/835/2/211.
Zhang, Quanhao, Wang, Yuming, Hu, Youqiu, Liu, Rui, and Liu, Jiajia, E-mail: zhangqh@mail.ustc.edu.cn. Wed . "Influence of Photospheric Magnetic Conditions on the Catastrophic Behaviors of Flux Ropes in Solar Active Regions". United States. doi:10.3847/1538-4357/835/2/211.
@article{osti_22663922,
title = {Influence of Photospheric Magnetic Conditions on the Catastrophic Behaviors of Flux Ropes in Solar Active Regions},
author = {Zhang, Quanhao and Wang, Yuming and Hu, Youqiu and Liu, Rui and Liu, Jiajia, E-mail: zhangqh@mail.ustc.edu.cn},
abstractNote = {Since only the magnetic conditions at the photosphere can be routinely observed in current observations, it is of great significance to determine the influences of photospheric magnetic conditions on solar eruptive activities. Previous studies about catastrophe indicated that the magnetic system consisting of a flux rope in a partially open bipolar field is subject to catastrophe, but not if the bipolar field is completely closed under the same specified photospheric conditions. In order to investigate the influence of the photospheric magnetic conditions on the catastrophic behavior of this system, we expand upon the 2.5-dimensional ideal magnetohydrodynamic model in Cartesian coordinates to simulate the evolution of the equilibrium states of the system under different photospheric flux distributions. Our simulation results reveal that a catastrophe occurs only when the photospheric flux is not concentrated too much toward the polarity inversion line and the source regions of the bipolar field are not too weak; otherwise no catastrophe occurs. As a result, under certain photospheric conditions, a catastrophe could take place in a completely closed configuration, whereas it ceases to exist in a partially open configuration. This indicates that whether the background field is completely closed or partially open is not the only necessary condition for the existence of catastrophe, and that the photospheric conditions also play a crucial role in the catastrophic behavior of the flux rope system.},
doi = {10.3847/1538-4357/835/2/211},
journal = {Astrophysical Journal},
number = 2,
volume = 835,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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