scholarly journals Catastrophic Eruption of Magnetic Flux Rope in the Corona and Solar Wind With and Without Magnetic Reconnection

2007 ◽  
Vol 665 (2) ◽  
pp. 1421-1427 ◽  
Author(s):  
Y. Chen ◽  
Y. Q. Hu ◽  
S. J. Sun
1999 ◽  
Author(s):  
C. J. Farrugia ◽  
L. A. Janoo ◽  
R. B. Torbert ◽  
J. M. Quinn ◽  
K. W. Ogilvie ◽  
...  

2020 ◽  
Vol 644 ◽  
pp. A137
Author(s):  
A. W. James ◽  
L. M. Green ◽  
L. van Driel-Gesztelyi ◽  
G. Valori

Context. Many previous studies have shown that the magnetic precursor of a coronal mass ejection (CME) takes the form of a magnetic flux rope, and a subset of them have become known as “hot flux ropes” due to their emission signatures in ∼10 MK plasma. Aims. We seek to identify the processes by which these hot flux ropes form, with a view of developing our understanding of CMEs and thereby improving space weather forecasts. Methods. Extreme-ultraviolet observations were used to identify five pre-eruptive hot flux ropes in the solar corona and study how they evolved. Confined flares were observed in the hours and days before each flux rope erupted, and these were used as indicators of episodic bursts of magnetic reconnection by which each flux rope formed. The evolution of the photospheric magnetic field was observed during each formation period to identify the process(es) that enabled magnetic reconnection to occur in the β <  1 corona and form the flux ropes. Results. The confined flares were found to be homologous events and suggest flux rope formation times that range from 18 hours to 5 days. Throughout these periods, fragments of photospheric magnetic flux were observed to orbit around each other in sunspots where the flux ropes had a footpoint. Active regions with right-handed (left-handed) twisted magnetic flux exhibited clockwise (anticlockwise) orbiting motions, and right-handed (left-handed) flux ropes formed. Conclusions. We infer that the orbital motions of photospheric magnetic flux fragments about each other bring magnetic flux tubes together in the corona, enabling component reconnection that forms a magnetic flux rope above a flaring arcade. This represents a novel trigger mechanism for solar eruptions and should be considered when predicting solar magnetic activity.


2004 ◽  
Vol 13 (08) ◽  
pp. 1007-1019
Author(s):  
ELIZABETH L. BOUZARTH ◽  
DAVID RICHESON

We introduce topological helicity, an invariant for oriented framed links. Topological helicity provides an elementary means of computing helicity for a magnetic flux rope by measuring its knotting, linking, and twisting. We present an equivalence relation, reconnection-equivalence, for framed links and prove that topological helicity is a complete invariant for the resulting equivalence classes. We conclude by showing that one can use magnetic reconnection to transform one collection of linked flux ropes into another collection if and only if they have the same helicity.


2020 ◽  
Vol 890 (1) ◽  
pp. 10 ◽  
Author(s):  
Peng Zou ◽  
Chaowei Jiang ◽  
Fengsi Wei ◽  
Xueshang Feng ◽  
Pingbing Zuo ◽  
...  

2010 ◽  
Vol 719 (1) ◽  
pp. L36-L40 ◽  
Author(s):  
J. T. Gosling ◽  
W.-L. Teh ◽  
S. Eriksson

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Wensi Wang ◽  
Rui Liu ◽  
Yuming Wang ◽  
Qiang Hu ◽  
Chenglong Shen ◽  
...  

2012 ◽  
Vol 117 (A9) ◽  
pp. n/a-n/a ◽  
Author(s):  
H. Hasegawa ◽  
H. Zhang ◽  
Y. Lin ◽  
B. U. Ö. Sonnerup ◽  
S. J. Schwartz ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document