Tag Archives: flux emergence

121. The Origin of Major Solar Activity: Collisional Shearing between Nonconjugated Polarities of Multiple Bipoles Emerging within Active Regions

Contributed by Georgios Chintzoglou. Posted on February 28, 2019

Magnetic flux of opposite polarities belonging to two different emerging/emerged bipoles inside multipolar magnetic regions, can experience “collisional shearing”, a process resulting in strong shearing and fast cancellation of magnetic flux near the polarity inversion line. This type of flux cancellation is found to be the cause of a succession of major flares and CMEs in complex active regions.

119. Roles of Photospheric Motions and Flux Emergence in the Major Solar Eruption on 2017 September 6

Contributed by Rui Wang. Posted on January 31, 2019

Both magnetic flux emergence and shearing flows occurred before the X9.3 flare on 2017 September 6. This analysis shows that shearing flows played a more significant role in leading to the helicity and electric currents buildup before the major eruption.

87. Magnetic Reconnection at the Earliest Stage of Solar Flux Emergence

Contributed by Hui Tian. Posted on March 1, 2018

The early phase of a flux emergence was observed by IRIS, and spectra of the accompanying UV bursts are analyzed. Many bursts appear to be associated with the magnetic flux cancellation, and almost all of them are located in regions with large squashing factors.

79. Homologous Circular-Ribbon Flares Driven by Twisted Flux Emergence

Contributed by Zhi Xu. Posted on December 18, 2017

Two homologous circular-ribbon flares associated with two filament eruptions were observed and analyzed. The emergence of magnetic flux ropes helped to inject free energy into the region and drive the magnetic reconnection above it.

60. SDO/HMI Survey of Emerging Active Regions for Helioseismology and Other Solar Physics Applications (SDO/HEAR)

Contributed by Hannah Schunker. Posted on September 28, 2016

We have generated a dataset of emerging active regions (EARs) observed by SDO/HMI that is specifically suitable for helioseismic analysis. Using this dataset we show that, on average the bipoles have a symmetric the east-west velocity relative to differential rotation.