Magnetohydrodynamics evolution of three-dimensional magnetic null in NOAA active region 11515 initiated using non-force-free field extrapolation by Sanjay Kumar, Avijeet Prasad, Avijeet Prasad, Ranadeep Sarkar, Ramit Bhattacharyya

“…The simulation is conducted using an extrapolated non-force-free magnetic field generated from the photospheric vector magnetogram of the active region as the initial magnetic field. …”
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Element Abundances in Impulsive Solar Energetic Particle Events by J. Martin Laming, Natsuha Kuroda

“…The ponderomotive force causing the fractionation must be due to torsional Alfvén waves, which couple much less effectively to slow modes than do shear waves, and upward-propagating acoustic waves deriving from photospheric convection must be effectively mode-converted to fast modes at the chromospheric layer, where Alfvén and sound speeds are equal, and subsequently totally internally reflected. …”
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SN 2020udy: A New Piece of the Homogeneous Bright Group in the Diverse Iax Subclass by Mridweeka Singh, Devendra K. Sahu, Barnabás Barna, Anjasha Gangopadhyay, Raya Dastidar, Rishabh Singh Teja, Kuntal Misra, D. Andrew Howell, Xiaofeng Wang, Jun Mo, Shengyu Yan, Daichi Hiramatsu, Craig Pellegrino, G. C. Anupama, Arti Joshi, K. Azalee Bostroem, Jamison Burke, Curtis McCully, Rama Subramanian V, Gaici Li, Gaobo Xi, Xin Li, Zhitong Li, Shubham Srivastav, Hyobin Im, Anirban Dutta

“…Unlike in the case of normal type Ia SNe, the photospheric approximation remains robust until +100 days, requiring an additional continuum source. …”
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Hybrid Data-driven Magnetofrictional and Magnetohydrodynamic Simulations of an Eruptive Solar Active Region by Andrey N. Afanasyev, Yuhong Fan, Maria D. Kazachenko, Mark C. M. Cheung

“…First, we apply the MF approach to build the coronal magnetic configuration corresponding to the SDO/HMI photospheric magnetograms by using the JSOC PDFI_SS electric field inversions at the bottom boundary of the simulation domain. …”
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Field Line Universal relaXer (FLUX): A Fluxon Approach to Coronal Magnetic Field Modeling by Chris Lowder, Chris Gilly, Craig DeForest

“…We describe a novel method for modeling the global, steady solar wind using photospheric magnetic fields as a driving boundary condition. …”
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Investigations of Flaring Plasma Parameters during an M-class Flare Using the Differential Evolution Method and XSM/Chandrayaan-2 Observations by Anna Kępa, Marek Siarkowski, Arun Kumar Awasthi, Janusz Sylwester, Barbara Sylwester

“…The results reveal notable variations in elemental abundances between photospheric and coronal values during different flare phases. …”
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Observational Signatures of Coronal Heating in Magnetohydrodynamic Simulations without Radiation or a Lower Atmosphere by James A. Klimchuk, Kalman J. Knizhnik, Vadim M. Uritsky

“…We have used it to predict the emission from a model corona that is driven by vortical boundary motions meant to represent photospheric convection. We find that individual magnetic strands experience short-term brightenings, both scattered throughout the computational volume and in localized clusters. …”
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Global Solar Magnetic Field Evolution Over 4 Solar Cycles: Use of the McIntosh Archive by David F. Webb, Sarah E. Gibson, Ian M. Hewins, Robert H. McFadden, Barbara A. Emery, Barbara A. Emery, Anna Malanushenko, Thomas A. Kuchar

“…McIntosh used mainly Hα, He-I 10830 Å and photospheric magnetic measurements from both ground-based and NASA satellite observations. …”
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Formation of Polar Crown Filament Magnetic Fields by Supergranular Helicity Injection by Huanxin Chen, Chun Xia, Hechao Chen

“…The Coriolis-effect-induced vortical motions at the boundaries of several supergranular cells inject magnetic helicity from the photospheric boundary into the solar atmosphere. Supergranular-scale helicity injection, transfer, and condensation produce strongly sheared magnetic fields. …”
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The thickness of current sheets and implications for coronal heating by James A. Klimchuk, James E. Leake, Lars K. S. Daldorff, Lars K. S. Daldorff, Craig D. Johnston, Craig D. Johnston

“…Finally, we argue that some quasi-statically evolving current sheets undergoing slow stressing—e.g., when the coronal magnetic field is subjected to photospheric boundary driving—may reach a critical shear, at which point they lose equilibrium, spontaneously collapse, and reconnect. …”
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On the 3He anomaly in hot subdwarf B stars by Schneider David, Irrgang Andreas, Heber Ulrich, Nieva Maria F., Przybilla Norbert

“…Quantitative spectral analyses of high-resolution spectra to derive photospheric isotopic helium abundance ratios for known 3He sdBs have not been performed yet. …”
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Data-constrained MHD Simulation of a Multi-ribbon Flare Corresponding to a Successful and a Confined Eruption by Wentai Fu, Yang Guo, Mingde Ding, Ze Zhong, Ye Qiu

“…We obtain the coronal magnetic configuration for this region, using a nonlinear force-free field extrapolation based on the photospheric magnetogram at 12:00 UT. Taking this as the initial condition, we perform a data-constrained MHD simulation to study the evolution of the magnetic topology for this region. …”
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Coronal Heating and Solar Wind Generation by Flux Cancellation Reconnection by D. I. Pontin, E. R. Priest, L. P. Chitta, V. S. Titov

“…We conclude that through two phases of atmospheric energy release—precancellation and cancellation—the cancellation of photospheric magnetic flux fragments and the associated magnetic reconnection may provide a substantial energy and mass flux contribution to coronal heating and solar wind generation.…”
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A Large-Scale Dataset of Three-Dimensional Solar Magnetic Fields Extrapolated by Nonlinear Force-Free Method by Zhongrui Zhao, Long Xu, Xiaoshuai Zhu, Xinze Zhang, Sixuan Liu, Xin Huang, Zhixiang Ren, Yonghong Tian

“…Thus, it is extremely important to reconstruct three-dimentional (3D) magnetic field of solar corona from really observed photospheric magnetogram. In this paper, a large-scale dataset of 3D solar magnetic fields of active regions is built by using the nonlinear force-free magnetic field (NLFFF) extrapolation from vector magnetograms of Helioseismic and Magnetic Imager (HMI) on Solar Dynamics Observatory (SDO). …”
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Young Stellar Objects, Accretion Disks, and Their Variability with Rubin Observatory LSST by R. Bonito, L. Venuti, S. Ustamujic, P. Yoachim, R. A. Street, L. Prisinzano, P. Hartigan, M. G. Guarcello, K. G. Stassun, T. Giannini, E. D. Feigelson, A. Caratti o Garatti, S. Orlando, W. I. Clarkson, P. McGehee, E. C. Bellm, J. E. Gizis

“…Indeed, both short-term variability (on timescales of hours to days) and long-term variability (months to years), predominantly driven by the dynamics of accretion processes in disk-hosting YSOs, can be explored by taking advantage of the multiband filters option available in Rubin LSST, in particular the u , g , r , i filters that enable us to discriminate between photospheric stellar properties and accretion signatures. …”
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Searching for Intermediate-mass Black Holes in Globular Clusters through Tidal Disruption Events by Vivian L. Tang, Piero Madau, Elisa Bortolas, Eric W. Peng, Yuting Feng, Puragra Guhathakurta

“…We model the long super-Eddington accretion phase and ensuing optical flare, and derive the disruption rate of main-sequence stars as a function of black hole mass and GC properties with the help of a 1D Fokker–Planck approach. The photospheric emission of the adiabatically expanding outflow dominates the observable radiation and peaks in the near-ultraviolet/optical bands, outshining the brightness of the (old) stellar population of GCs in Virgo for a period of months to years. …”
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The Temporal and Spatial Evolution of Magnetohydrodynamic Wave Modes in Sunspots by A. B. Albidah, V. Fedun, A. A. Aldhafeeri, I. Ballai, D. B. Jess, W. Brevis, J. Higham, M. Stangalini, S. S. A. Silva, C. D. MacBride, G. Verth

“…The proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) techniques were used to analyze 3 and 6 hr Solar Dynamics Observatory/Helioseismic and Magnetic Imager time series of Doppler velocities at the photospheric level of approximately circular and elliptically shaped sunspots. …”
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Self-similar Outflows at the Source of the Fast Solar Wind: A Smoking Gun of Multiscale Impulsive Reconnection? by Vadim M. Uritsky, Judith T. Karpen, Nour E. Raouafi, Pankaj Kumar, C. Richard DeVore, Craig E. Deforest

“…For the first time, we demonstrate that the polar coronal-hole outflows obey a family of power-law probability distributions characteristic of impulsive interchange magnetic reconnection. Turbulent photospheric driving may play a crucial role in releasing magnetically confined plasma onto open field. …”
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OPEN GEOSPATIAL DATA FOR URBAN GREEN AREAS by M. Baučić, F. Gilić, S. Bačić, T. Duplančić-Leder

“…As spaceborne images, Sentinel-2 satellite images were used and as street-level images, Google Street View 360° photospheres have been utilized. From both sources, information about current greenery status was automatically extracted. …”
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Advanced Γ Method for Small-scale Vortex Detection in the Solar Atmosphere by Yuyang Yuan, Suzana de Souza e Almeida Silva, Viktor Fedun, Irina N. Kitiashvili, Gary Verth

“…This method is applied to detect and analyze the photospheric vortices in 3D realistic magnetoconvection numerical and observational data. …”
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