А. Г. Косовичев

ar-emergence-transformers: Code for Forecasting Solar Active Region Emergence using Transformers

S J Patil, Spiridon Kasapis, Eren Dogan, John T. Stefan et autres

This repository contains the code, models, and evaluation scripts used in the paper “Forecasting Continuum Intensity for Solar Active Region Emergence Prediction using Transformers”. It includes training pipelines, pre-trained model checkpoints, evaluation routines, and reproducibility tools implemented in PyTorch. This archived release …

us (code pays fourni par la source)

ar-emergence-transformers: Code for Forecasting Solar Active Region Emergence using Transformers

S J Patil, Spiridon Kasapis, Eren Dogan, John T. Stefan et autres

This repository contains the code, models, and evaluation scripts used in the paper “Forecasting Continuum Intensity for Solar Active Region Emergence Prediction using Transformers”. It includes training pipelines, pre-trained model checkpoints, evaluation routines, and reproducibility tools implemented in PyTorch. This archived release …

us (code pays fourni par la source)

Time-dependence of Subsurface Solar Convection Using the Time–Distance Deep-focus Method

John T. Stefan, А. Г. Косовичев, Gustavo Guerrero, Andrey M. Stejko

Abstract We reexamine 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 was found to be significantly weaker than predicted by theory and simulations. The Global …

us, br (code pays fourni par la source)

Helioseismic Evidence That the Solar Dynamo Originates near the Tachocline

Krishnendu Mandal, А. Г. Косовичев

The exact location of the solar dynamo remains uncertain--whether it operates primarily in the near-surface shear layer, throughout the entire convection zone, or near the tachocline, a region of sharp transition in the solar rotation, located at the base of the convection …

Helioseismic Evidence That the Solar Dynamo Originates near the Tachocline

Krishnendu Mandal, А. Г. Косовичев

The exact location of the solar dynamo remains uncertain--whether it operates primarily in the near-surface shear layer, throughout the entire convection zone, or near the tachocline, a region of sharp transition in the solar rotation, located at the base of the convection …

3D Radiative MHD Modeling of Particle Beam Heating of the Solar Atmosphere

Samuel Granovsky, А. Г. Косовичев, Irina Kitiashvili, A. A. Wray

While solar flares are primarily associated with enhanced ultraviolet and X-ray emission, a subset of flares exhibit significant continuum brightening in visible light and are classified as white-light flares (WLFs). Despite extensive observational and modeling efforts, the physical mechanisms responsible for the …

3D Radiative MHD Modeling of Particle Beam Heating of the Solar Atmosphere

Samuel Granovsky, А. Г. Косовичев, Irina Kitiashvili, A. A. Wray

While solar flares are primarily associated with enhanced ultraviolet and X-ray emission, a subset of flares exhibit significant continuum brightening in visible light and are classified as white-light flares (WLFs). Despite extensive observational and modeling efforts, the physical mechanisms responsible for the …

us (code pays fourni par la source)

Investigating Variations in Solar Differential Rotation by Helioseismology

Krishnendu Mandal, А. Г. Косовичев, В. В. Пипин, S. G. Korzennik

Abstract Helioseismic signatures of dynamo waves have recently been discovered in variations of the solar differential rotation, offering valuable insights into the type of dynamo mechanism operating in the solar convection zone. To characterize these variations, we analyze p -mode frequency-splitting data …

Prediction of Intensity Variations Associated with Emerging Active Regions using Helioseismic Power Maps and Machine Learning

Spiridon Kasapis, Irina Kitiashvili, А. Г. Косовичев, John T. Stefan

Abstract We developed recurrent neural networks using the long short-term memory (LSTM) architecture to predict the decrease in continuum intensity linked to the emergence of active regions (ARs), before they become visible on the solar surface and start forming sunspots. The goal …

Properties of Turbulent Convection and Large-scale Flows in a Rotating F-type Star Revealed by 3D Realistic Radiative Hydrodynamic Simulations

Irina Kitiashvili, А. Г. Косовичев, A. A. Wray

Abstract The nonlinear coupling between stellar convection and rotation is of great interest because it relates to understanding both stellar evolution and activity. We investigate the influence of rotation and the Coriolis force on the dynamics and thermodynamic structure of an F-type …

Helicity Fluxes and Hemispheric Helicity Rule of Active Regions Emerging from the Convection Zone Dynamo

В. В. Пипин, Shangbin Yang, А. Г. Косовичев

Abstract Using a 3D nonlinear mean field solar dynamo model, we investigate the magnetic helicity flux and magnetic twist, as well as tilt parameters of bipolar magnetic regions (BMRs) emerging from the solar convection zone owing to the magnetic buoyancy instability. The …

An Acoustic Model for Sunquakes Unifying the Solar Interior and Atmosphere

John T. Stefan, А. Г. Косовичев

One of the leading hypotheses for sunquake generation suggests that flare-accelerated particles originating from the reconnection site in the corona travel down to the chromosphere and photosphere, where they deposit energy through collisions and subsequently drive acoustic oscillations. To properly encompass this …