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Solar inertial modes are quasi-toroidal modes of the Sun that are of practical interest as they allow probing the deep convection zone. Since 2010, solar images of the photospheric magnetic field are made available by HMI onboard the Solar…

Solar and Stellar Astrophysics · Physics 2025-02-10 Neelanchal Joshi , Zhi-Chao Liang , Damien Fournier , Laurent Gizon

Dynamic Mode Decomposition (DMD) is a data-driven and model-free decomposition technique. It is suitable for revealing spatio-temporal features of both numerically and experimentally acquired data. Conceptually, DMD performs a…

Fluid Dynamics · Physics 2020-12-18 Tim Krake , Stefan Reinhardt , Marcel Hlawatsch , Bernhard Eberhardt , Daniel Weiskopf

We introduce two new methods that are designed to improve the realism and utility of large, active region-scale 3D MHD models of the solar atmosphere. We apply these methods to RADMHD, a code capable of modeling the Sun's upper convection…

Solar and Stellar Astrophysics · Physics 2010-05-06 William P. Abbett , George H. Fisher

Solar flares are explosive events in the solar corona, representing fast conversion of magnetic energy into thermal and kinetic energy, and hence radiation, due to magnetic reconnection. Modelling is essential for understanding and…

Solar and Stellar Astrophysics · Physics 2019-02-13 M. Gordovskyy , P. K. Browning , R. F. Pinto

There is a broad need in the neuroscience community to understand and visualize large-scale recordings of neural activity, big data acquired by tens or hundreds of electrodes simultaneously recording dynamic brain activity over minutes to…

Neurons and Cognition · Quantitative Biology 2015-11-24 Bingni W. Brunton , Lise A. Johnson , Jeffrey G. Ojemann , J. Nathan Kutz

Quantitative models of sunspot and starspot decay predict the timescale of magnetic diffusion and may yield important constraints in stellar dynamo models. Motivated by recent measurements of starspot lifetimes, we investigate the…

Solar and Stellar Astrophysics · Physics 2017-01-18 Yuri E. Litvinenko , M. S. Wheatland

Mutual conversion of various kinds of magnetohydrodynamic (MHD) waves can have profound impacts on wave propagation, energy transfer, and heating of the solar chromosphere and corona. Mode conversion occurs when an MHD wave travels through…

Solar and Stellar Astrophysics · Physics 2024-04-01 Pankaj Kumar , Valery M. Nakariakov , Judith T. Karpen , Kyung-Suk Cho

In order to assess the ability of helioseismology to probe the subsurface structure and magnetic field of sunspots, we need to determine how helioseismic travel times depend on perturbations to sunspot models. Here we numerically simulate…

Solar and Stellar Astrophysics · Physics 2015-06-15 Hannah Schunker , Laurent Gizon , Robert H. Cameron , Aaron C. Birch

The areas of sunspots are the most prominent feature of the development of sunspot groups. Since the size of sunspot areas depend on the strength of the magnetic field, accurate measurements of these areas are important. In this study, a…

Solar and Stellar Astrophysics · Physics 2015-06-19 H. Cakmak

The increased amount of information provided by ongoing missions such as the Solar Dynamics Observatory (SDO) represents a great challenge for the understanding of basic questions such as the internal structure of sunspots and how they…

Solar and Stellar Astrophysics · Physics 2013-10-29 R. Gafeira , C. C. Fonte , M. A. Pais , J. Fernandes

A quantitative study of the observable radio signatures of the sausage, kink, and torsional MHD oscillation modes in flaring coronal loops is performed. Considering first non-zero order effect of these various MHD oscillation modes on the…

Solar and Stellar Astrophysics · Physics 2015-06-03 George Mossessian , Gregory D. Fleishman

Seasonal time series exhibit intricate long-term dependencies, posing a significant challenge for accurate future prediction. This paper introduces the Multi-scale Seasonal Decomposition Model (MSSD) for seasonal time-series forecasting.…

Machine Learning · Computer Science 2024-12-18 Yining Pang , Chenghan Li

Observations in the solar wind suggest that the compressive component of inertial-range solar-wind turbulence is dominated by slow modes. The low collisionality of the solar wind allows for non-thermal features to survive, which suggests…

Space Physics · Physics 2017-05-19 Daniel Verscharen , Christopher H. K. Chen , Robert T. Wicks

Magnetic bright points on the solar photosphere mark the footpoints of kilogauss magnetic flux tubes extending toward the corona. Convective buffeting of these tubes is believed to excite magnetohydrodynamic waves, which can propagate to…

Solar and Stellar Astrophysics · Physics 2024-02-20 Samuel J. Van Kooten , Steven R. Cranmer

The interaction of multiple fluids through a heterogeneous pore space leads to complex pore-scale flow dynamics, such as intermittent pathway flow. The non-local nature of these dynamics, and the size of the 4D datasets acquired to capture…

Slowly rotating magnetic massive stars develop "dynamical magnetospheres" (DM's), characterized by trapping of stellar wind outflow in closed magnetic loops, shock heating from collision of the upflow from opposite loop footpoints, and…

Solar and Stellar Astrophysics · Physics 2016-09-07 Stanley P. Owocki , Asif ud-Doula , Jon O. Sundqvist , Veronique Petit , David H. Cohen , Richard H. D. Townsend

We report the observations of the magneto-hydrodynamic waves propagating along magnetic flux tubes in the solar photosphere. We identified 20 isolated strong peaks (8 peaks for pores and 12 peaks for inter-granular magnetic structure) in…

Solar and Stellar Astrophysics · Physics 2015-05-13 Daisuke Fujimura , Saku Tsuneta

Magnetohydrodynamic (MHD) waves are routinely observed in the solar atmosphere. These waves are important in the context of solar physics as it is widely believed they can contribute to the energy budget of the solar atmosphere and are a…

Solar and Stellar Astrophysics · Physics 2021-12-22 Samuel Skirvin , Viktor Fedun , Suzana Silva , Gary Verth

The variation of solar irradiance is one of the natural forcing mechanisms of the terrestrial climate. Hence, the time-dependent solar irradiance is an important input parameter for climate modelling. The solar surface magnetic field is a…

Solar and Stellar Astrophysics · Physics 2015-05-11 Omar Ashamari , Rami Qahwaji , Stan Ipson , Micha Scholl , Omar Nibouche , Margit Haberreiter

There is observational evidence of propagating kink waves driven by photospheric motions. These disturbances, interpreted as kink magnetohydrodynamic (MHD) waves are attenuated as they propagate upwards in the solar corona. In this paper we…

Solar and Stellar Astrophysics · Physics 2015-05-18 J. Terradas , M. Goossens , G. Verth