9 citations · 45 across the 11 of their papers we have counts for
12 papers · 1 filter
Time-Dependence of Subsurface Solar Convection Using the Time-Distance Deep-Focus Method
John T. Stefan, Alexander G. Kosovichev, Gustavo Guerrero +1
We re-examine the deep-focus methodology of time-distance helioseismology previously used to estimate the power spectrum of the solar convection at a depth of about 30 Mm, which wa…
Can Proton Beam Heating Flare Models Explain Sunquakes?
Viacheslav Sadykov, John Stefan, Alexander Kosovichev +4
SDO/HMI observations reveal a class of solar flares with substantial energy and momentum impacts in the photosphere, concurrent with white-light emission and helioseismic responses…
The Puzzling Structure of Solar Convection: Window into the Dynamo
Nicholas A. Featherstone, Kyle C. Augustson, Jonathan M. Aurnou +25
The operation of the solar dynamo, with all of its remarkable spatio-temporal ordering, remains an outstanding problem of modern solar physics. A number of mechanisms that might pl…
Implicit large eddy simulations of global solar convection: effects of numerical resolution in non-rotating and rotating cases
G. Guerrero, A. M. Stejko, A. G. Kosovichev +2
Simulating deep solar convection and its coupled mean-field motions is a formidable challenge where few observational results constrain models that suffer from the non-physical inf…
Constraining Global Solar Models through Helioseismic Analysis
Andrey M. Stejko, Alexander G. Kosovichev, Nicholas A. Featherstone +4
Global hydrodynamic simulations of internal solar dynamics have focused on replicating the conditions for solar-like differential rotation and meridional circulation using the resu…
Advances and Challenges in Observations and Modeling of the Global-Sun Dynamics and Dynamo
A. G. Kosovichev, G. Guerrero, A. M. Stejko +2
Computational heliophysics has shed light on the fundamental physical processes inside the Sun, such as the differential rotation, meridional circulation, and dynamo-generation of…
Forward Modeling Helioseismic Signatures of One- and Two-cell Meridional Circulation
Andrey M. Stejko, Alexander G. Kosovichev, Valery V. Pipin
Using a 3D global solver of the linearized Euler equations, we model acoustic oscillations over background velocity flow fields of single-cell meridional circulation with deep and…
Helioseismic Modeling of Background Flows
Andrey M. Stejko, Alexander G. Kosovichev, Nagi N. Mansour
We present a 3-dimensional (3D) numerical solver of the linearized compressible Euler equations (GALE -- Global Acoustic Linearized Euler), used to model acoustic oscillations thro…
Analysis of Time-Distance Helioseismology for Detection of Emerging Active Regions
John T. Stefan, Alexander G. Kosovichev, Andrey M. Stejko
A time-distance helioseismic technique, similar to the one used by Ilonidis et al (2011), is applied to two independent numerical models of subsurface sound-speed perturbations to…
Machine Learning in Heliophysics and Space Weather Forecasting: A White Paper of Findings and Recommendations
Gelu Nita, Manolis Georgoulis, Irina Kitiashvili +38
The authors of this white paper met on 16-17 January 2020 at the New Jersey Institute of Technology, Newark, NJ, for a 2-day workshop that brought together a group of heliophysicis…
3D MHD Modeling of the Impact of Subsurface Stratification on the Solar Dynamo
Andrey M. Stejko, Gustavo Guerrero, Alexander G. Kosovichev +1
Various models of solar subsurface stratification are tested in the global EULAG-MHD solver to simulate diverse regimes of near-surface convective transport. Sub- and superadiabaci…
3D Global MHD Modeling of Solar Subsurface Convection
Andrey M. Stejko, Gustavo Guerrero, Alexander G. Kosovichev +1
Various models of solar sub-surface stratification are tested in the global EULAG-MHD solver to simulate diverse regimes of near-surface convective transport. Sub- and superadiabac…