Moreton waves were studied using a systematic survey of Moreton-wave events observed during the SDO era. The results showed that inclined magnetic configurations act as a wall, forcing eruptions and Moreton waves to propagate toward weaker magnetic fields.
A few major geoeffective flares and CMEs occurred in May 2024. HMI magnetic field data were used to examine how the flares occurred and why they became geoeffective.
The coronal magnetic field evolution of the AR 11429 was simulated using time-dependent magneto-friction model. The model reproduced the magnetic structure that has remarkable correspondence with the spatial characteristics in coronal extreme ultraviolet images.
Magnetic power spectra were calculated using MDI and HMI data for two solar cycles. It is found that the sizes of the magnetic networks do not show a cycle dependence, but the power-law indices estimated from the active region and network sizes show an anti-correlation with the sunspot numbers.
This study analyzes a few properties of evolving bipolar magnetic regions: separation of polarities, tilt angles, and tilt angle and flux relations. The analysis supports that the bipolar regions form from thin-flux tubes and Coriolis force plays an important role in forming the regions.
The advective flux transport model, coupled with a random active region generator, predicts that the solar activity will peak in the northern hemisphere around August 2024, and peak in the southern hemisphere around February 2025.
Equatorial Rossby waves are detected using the HMI’s time-distance subsurface flow fields. It is also found that the power of the Rossby waves show a positive correlation with the sunspot number, while the frequency of the waves shows an anti-correlation with the sunspot number.
HMI magnetic field synoptic maps are used to evaluate the magnetic field structures’ organization and propagation as a function of time and latitude. It is demonstrated that the organization of longitudinal structures observed on synoptic maps is proportional to the level of activity at given latitudes.
This study reveals correlations between the motion of pores and the maximum magnetic pressure difference at their opposite edges, but no causal relationship between the two is found.
The CGEM team identified and corrected two artifacts that had affected the electric field calculation for a small number of active regions.