Research Highlights

Sarah Gibson, et al. present a comprehensive study for a filament-embedding active region as determined from observations from multiple facilities including the Chinese Hα Solar Explorer (CHASE). The spectral resolution of CHASE is as high as 0.024 ̊A pixel−1, which enables an accurate determination of the chromospheric Doppler velocity that is especially crucial for probing the relative stable structure investigated here. 

Anett Elek, Marianna B. Korsós, Mausumi Dikpati, Norbert G. Gyenge, Bernadett Belucz, and Robertus Erdélyi, using data from the Debrecen Solar Faculae Database, investigated the spatiotemporal distribution of photospheric faculae between 2010 May 1 and 2014 December 31. Photospheric faculae are markers of the solar magnetic field, appearing as bright regions along the edges of granules on the Sun's surface.

Kun Wu, Liying Qian, Wenbin Wang, Xuguang Cai, Joseph M. Mclnerney investigate in detail the occurrence and evolution of ionospheric equatorial plasma bubbles (EPBs) during a moderate storm on September 17th, 2021, using Global-scale Observation of the Limb and Disk (GOLD) observations and Whole Atmosphere Community Climate Model-eXtended (WACCM-X) simulations.

Matthias Rempel, Georgios Chintzoglou, Mark C. M. Cheung, Yuhong Fan, and Lucia Kleint present a new simulation setup using the MURaM radiative Magnetohydrodynamic (MHD) code that allows to study the formation of collisional polarity inversion lines (cPILs) in the photosphere and the coronal response including flares. In this scheme we start with a bipolar sunspot configuration and set the spots on collision course by imposing the appropriate velocity field at the footpoints in the subphotospheric boundary.

Kinfe Teweldebirhan, Mark Miesch, and Sarah Gibson investigate the role and impact of converging flows toward Bipolar Magnetic Regions (BMR inflows) on the Sun’s global solar dynamo. These flows are large-scale physical phenomena that have been observed and so should be included in any comprehensive solar dynamo model.

Chun-Yen Huang, Tzu-Wei Fang, Arthur Richmond, Timothy Fuller-Rowell, Jenn-Yenq Liu research expressions of newly established Rayleigh-Taylor (R-T) instability growth rates, then perform calculations using the thermospheric and ionospheric conditions based on the coupled Whole Atmosphere Model and Ionosphere Plasmasphere Electrodynamic model (WAM-IPE). The parameters used in this calculation include the field-line integrated conductivities and currents, which consider the Quasi-Dipole Coordinates and the modifications to the equations of electrodynamics.

D. F. Webb, B. A. Emery, S. E. Gibson, I. M. Hewins, R. H. McFadden , T. A. Kuchar examine the process during which the solar magnetic field reverses polarity around solar maximum using the McIntosh Archive (McA) of solar synoptic maps over five consecutive solar cycles, SCs 19-23 or from 1955 to 2009. This data set permits us to track features such as filaments, polarity inversion lines (PILs), coronal hole (CH) boundaries and sunspots over many consecutive Carrington rotations and solar cycles.

N. M. Pedatella, E. Aa, and A. Maute explore the influence of atmospheric planetary waves on the occurrence of irregularities in the low latitude ionosphere is investigated using Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (WACCM-X) simulations and Global Observations of the Limb and Disk (GOLD) observations. 

Sarah Gibson et al., review the properties of an irregularly shaped “Alfvén surface” surface and discuss its importance in models of solar wind acceleration, angular momentum transport, MHD waves and turbulence, and the geometry of closed coronal loops. We also review the results of simulations and data analysis techniques that aim to determine the location of the Alfvén surface.