108. Signatures of Solar Cycle 25 in Subsurface Zonal Flows
New helioseismic analysis of the Sun’s subsurface zonal flows shows the equator-migrating branch of the faster-than-average rotation, a sign of the Solar Cycle 25.
107. Cyclic Variations of the Sun’s Seismic Radius
The Sun’s seismic radius, measured from the frequencies of f modes, is determined using both MDI and HMI data, covering a total of 21 years. It is found that the seismic radius is reduced by 1-2 km during the maxima, but the largest change of the radius happens at about 5 Mm beneath the surface.
106. The vector magnetic field of the Sun-as-a-star during activity cycle 24
HMI-observed vector magnetic-field maps were lowered to a resolution of lmax=5, so that a comparison between solar and stellar magnetic field is possible.
105. Waves of Magnetic-field Variations Observed in a Flare-excited Sunquake Event
Waves of magnetic-field variations were observed associated with the sunquake waves that were excited by the X9.3 flare on 2017 September 6. The nature and cause of the magnetic waves are discussed after the phase relations and power distributions of the magnetic waves and Doppler-observed sunquake waves are investigated.
104. Analysis of the Effects of Sunspots in Their Quiet Surroundings
Ring-diagram analysis is applied on the HMI-observed sunspots of about 3 years. The attenuation of wave amplitudes near sunspots, rotational speed of sunspots, and subsurface flows around sunspots are discussed.
103. Enhancing SDO/HMI Images Using Deep Learning
A deep learning code is developed to enhance HMI continuum intensity images and line-of-sight magnetic field for a better spatial resolution.
102. Solar magnetic cycle and its variability in a 3D Babcock-Leighton dynamo model
Employing an updated Babcock–Leighton dynamo model, this study finds that the model with scattered tilt angles, which are around the Joy’s Law but with a standard deviation of 15°, is able to reproduce the observed variations of solar cycles.
101. Solar Open Flux Migration from Pole to Pole: Magnetic Field Reversal
Long-term migration of the Sun’s open magnetic flux is studied, and its relation with the sunspot numbers is discussed.
100. Observationally Quantified Reconnection Providing a Viable Mechanism for Active Region Coronal Heating
Heat flux delivered by magnetic reconnection is calculated based on a model using magnetic field observations, and the calculation is then compared with AIA EUV observations.
99. A Comparative Study between A Failed and A Successful Eruption Initiated from the Same Polarity Inversion Line in AR 11387
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.