Tag Archives: vector magnetogram

124. On Solar surface Electric field Estimation with 3 Poisson solvers (SEE3Po) for driving time-dependent MHD simulations of solar active regions

Contributed by Keiji Hayashi. Posted on April 28, 2019

An algorithm, which is to calculate the electric field in order to retrieve the time variations of solar surface magnetic field observed by HMI, was recently developed.

120. Magnetic Fields and the Supply of Low-Frequency Acoustic Waves to the Solar Chromosphere

Contributed by S. P. Rajaguru. Posted on February 27, 2019

Through analyzing simultaneous HMI’s visible-light observations and AIA’s ultraviolet observations, the authors show that a significant amount of acoustic waves with frequencies lower than the theoretical cutoff frequency can channel up along less inclined magnetic field from the photosphere to the chromosphere.

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.

92. Photospheric Magnetic Properties of Active Regions: Br or Blos?

Contributed by Jordan A. Guerra Aguilera. Posted on March 26, 2018

The majority of flare forecasting methods rely on observations of magnetic field on the Sun’s surface, but which observable, Br or Blos, is a better predictor? Through comparing a few magnetic properties derived from both observables, this nugget gives some suggestion.

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.