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Related papers: The Solar Memory From Hours to Decades

200 papers

Solar flares are transient yet dramatic events in the atmosphere of the Sun, during which a vast amount of magnetic energy is liberated. This energy is subsequently transported through the solar atmosphere or into the heliosphere, and…

Solar and Stellar Astrophysics · Physics 2022-12-14 Graham S. Kerr

Observational pre-cursors of large solar flares provide a basis for future operational systems for forecasting. Here, we study the evolution of the normalized emergence (EM), shearing (SH) and total (T) magnetic helicity flux components for…

Solar and Stellar Astrophysics · Physics 2022-02-09 Sz. Soós , M. B. Korsós , H. Morgan , R. Erdélyi

The hot and diffuse nature of the Sun's extended atmosphere allows it to persist in non-equilibrium states for long enough that wave-particle instabilities can arise and modify the evolution of the expanding solar wind. Determining which…

Parameters of magnetic activity on the solar type stars depend on the properties of the dynamo processes operating in stellar convection zones. We apply nonlinear mean-field axisymmetric $\alpha^2\Omega$ dynamo models to calculate of the…

Solar and Stellar Astrophysics · Physics 2015-05-08 V. V. Pipin

We analyze and model total solar irradiance variability on time scales from minutes to months, excluding variations due to p-mode oscillations, using a combination of convective and magnetic components. These include granulation, the…

Solar and Stellar Astrophysics · Physics 2013-03-11 Andrey D. Seleznyov , Sami K. Solanki , Natalie A. Krivova

We present a long short-term memory (LSTM) network for predicting whether an active region (AR) would produce a gamma-class flare within the next 24 hours. We consider three gamma classes, namely >=M5.0 class, >=M class, and >=C class, and…

Solar and Stellar Astrophysics · Physics 2019-06-06 Hao Liu , Chang Liu , Jason T. L. Wang , Haimin Wang

Self-organised critical avalanche models are a class of cellular automata that, despite their simplicity, can be applied to the modeling of solar (and stellar) flares and generate robust power-law distributions in event size measures.…

Solar and Stellar Astrophysics · Physics 2024-02-05 Henri Lamarre , Paul Charbonneau , Antoine Strugarek

We conduct a post hoc analysis of solar flare predictions made by a Long Short Term Memory (LSTM) model employing data in the form of Space-weather HMI Active Region Patches (SHARP) parameters calculated from data in proximity to the…

Solar and Stellar Astrophysics · Physics 2020-03-11 Hu Sun , Ward Manchester , Zhenbang Jiao , Xiantong Wang , Yang Chen

Variations of the sunspot number are important indicators of the solar activity cycles. The sunspot formation is a result of a dynamo process inside the Sun, which is far from being understood. We use simple dynamical models of the dynamo…

Astrophysics · Physics 2009-02-11 I. N. Kitiashvili , A. G. Kosovichev

Solar activity cycle varies in amplitude. The last Cycle 24 is the weakest in the past century. Sun's activity dominates Earth's space environment. The frequency and intensity of the Sun's activity are accordant with the solar cycle. Hence…

Solar and Stellar Astrophysics · Physics 2022-02-16 Wei Guo , Jie Jiang , Jing-Xiu Wang

Solar variability occurs over a broad range of spatial and temporal scales, from the Sun's brightening over its lifetime to the fluctuations commonly associated with magnetic activity over minutes to years. The latter activity includes most…

Solar and Stellar Astrophysics · Physics 2021-11-24 Valentina Penza , Francesco Berrilli , Luca Bertello , Matteo Cantoresi , Serena Criscuoli

Solar activity is studied using a cluster analysis of the time-fluctuations of the sunspot number. It is shown that in an Historic period the high activity components of the solar cycles exhibit strong clustering, whereas in a Modern period…

Astrophysics · Physics 2010-11-02 A. Bershadskii

We study the prediction of solar flare size and time-to-flare using 38 features describing magnetic complexity of the photospheric magnetic field. This work uses support vector regression to formulate a mapping from the 38-dimensional…

Solar and Stellar Astrophysics · Physics 2015-11-09 Laura E. Boucheron , Amani Al-Ghraibah , R. T. James McAteer

Solar flares are intense eruptive events caused by the rapid release of magnetic energy, often impacting Earth's space environment through electromagnetic radiation and high-energy particles. Accurate flare prediction is critical for space…

Solar and Stellar Astrophysics · Physics 2026-05-19 Limin Zhao , Xingyao Chen , Xiaoshuai Zhu , Dong Zhao , and Yihua Yan

The evolution of a solar model is initialized with homogeneous models of either, pre-main sequence (P-models) or, zero-age main sequence (Z-models). The zero-age of a solar model is conventionally referenced as the time where the nuclear…

Astrophysics · Physics 2008-11-26 P. Morel , J. Provost , G. Berthomieu

The physics of solar flares occurring on the Sun is highly complex and far from fully understood. However, observations show that solar eruptions are associated with the intense kilogauss fields of active regions, where free energies are…

Solar and Stellar Astrophysics · Physics 2024-01-26 Bach Viet Do , Yang Chen , XuanLong Nguyen , Ward Manchester

Large solar flares and eruptions may influence remote regions through perturbations in the outer-atmospheric magnetic field, leading to causally related events outside of the primary or triggering eruptions that are referred to as…

Solar and Stellar Astrophysics · Physics 2015-11-04 Carolus J. Schrijver , Paul A. Higgins

We present the first set of a new generation of models of massive stars of solar composition extending between 13 and 120 \msun, computed with and without the effects of rotation. We included two instabilities induced by rotation, namely…

Solar and Stellar Astrophysics · Physics 2012-12-13 Alessandro Chieffi , Marco Limongi

The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and the Earth's upper atmosphere (commonly referred to as space weather). These changes have a direct impact on the…

Solar and Stellar Astrophysics · Physics 2013-04-12 Andrés Muñoz-Jaramillo , María Dasi-Espuig , Laura A. Balmaceda , Edward E. DeLuca

Neutrinos generated during solar flares remain elusive. However, after $50$ years of discussion and search, the potential knowledge unleashed by their discovery keeps the search crucial. Neutrinos associated with solar flares provide…

Solar and Stellar Astrophysics · Physics 2020-10-12 K. Okamoto , Y. Nakano , S. Masuda , Y. Itow , M. Miyake , T. Terasawa , S. Ito , M. Nakahata