Tag Archives: eruption

192. Magnetic helicity and free magnetic energy as tools for probing eruptions in two differently evolving solar active regions

Contributed by Evangelia Liokati. Posted on July 29, 2023

An analysis of two active regions shows that differently evolving ARs may produce major eruptive flares even when, in addition to the accumulation of significant free magnetic energy budgets, they accumulate large amounts of both left- and right-handed helicity without a strong dominance of one handedness over the other.

138. Electric Current Neutralization in Solar Active Regions and Its Relation to Eruptive Activity

Contributed by Ellis Avallone. Posted on March 11, 2020

Electric current neutralization, which measures the ratio of direct current and return current inside active regions (ARs), is studied for a total of 30 AR samples. It is found that flare-productive ARs are more likely to exhibit non-neutralized currents than those flare-quiet ARs.

136. The Trigger Mechanism of Recurrent Solar Active Region Jets Revealed by the Magnetic Properties of a Coronal Geyser Site

Contributed by Alin Paraschiv. Posted on February 27, 2020

This study explores the magnetic triggers of recurrent active region jets. Both widely debated triggers, namely, flux cancellation and flux emergence, are associated alternatively to the apparently homologous jets.

135. Serial Flaring in an Active Region: Exploring Why Only One Flare is Eruptive

Contributed by Magnus Woods. Posted on February 26, 2020

Of three consecutive flares that occurred in a same active region within 4 hours, why were two non-eruptive and one eruptive? Non-linear force-free modeling suggest that breakout reconnection during the first two flares weakened the overlying field, allowing the flux rope to erupt in the third.

99. A Comparative Study between A Failed and A Successful Eruption Initiated from the Same Polarity Inversion Line in AR 11387

Contributed by Lijuan Liu. Posted on May 22, 2018

Two flares occurred in a same active region above a same polarity inversion line, but one had a failed CME eruption but another one had a successful CME eruption. This study explored why that was the case.

97. Successive X-class Flares and Coronal Mass Ejections Driven by Shearing Motion and Sunspot Rotation in Active Region NOAA 12673

Contributed by Xiaoli Yan. Posted on April 26, 2018

Shearing motions and sunspot rotations found in NOAA AR 12673 are believed to lead the free energy buildup and flux rope formation, which are responsible for the two successive X-class flares.

90. A Comparative Study of the Eruptive and Non-Eruptive Flares Produced by the Largest Active Region of Solar Cycle 24

Contributed by Ranadeep Sarkar. Posted on March 18, 2018

AR12192, the largest active region in Solar Cycle 24, produced 6 X-class flares, but none of them were associated with a CME. However, a much weaker flare, of M4.0-class, was associated with a CME. Magnetic field and morphological changes are analyzed during these flares to understand why this is the case.