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Related papers: Solar Flares and Magnetic Helicity

200 papers

We compute the change in the Lorentz force integrated over the outer solar atmosphere implied by observed changes in vector magnetograms that occur during large, eruptive solar flares. This force perturbation should be balanced by an equal…

Solar and Stellar Astrophysics · Physics 2011-12-06 George H. Fisher , David J. Bercik , Brian T. Welsch , Hugh S. Hudson

The magnetic field of the Sun drives a wide range of eruptive phenomena, from small-scale nanoflares to large flares and coronal mass ejections (CMEs). While direct observations of solar activity cover only the past few decades, indirect…

Solar and Stellar Astrophysics · Physics 2026-02-12 Valeriy Vasilyev , Natalie Krivova , Ilya Usoskin

High-resolution observations show the fine structure of the global equilibrium magnetic field configuration in solar atmosphere to be essentially different from that assumed in the traditional 'potential + force-free' field scenarios. The…

Solar and Stellar Astrophysics · Physics 2012-05-01 L. A. Pustil'nik , N. R. Ikhsanov , N. G. Beskrovnaya

Coronal mass ejections (CMEs) and solar flares are the large-scale and most energetic eruptive phenomena in our solar system and able to release a large quantity of plasma and magnetic flux from the solar atmosphere into the solar wind.…

Solar and Stellar Astrophysics · Physics 2017-07-13 X. Cheng , Y. Guo , M. D. Ding

A loss of magnetic field confinement is believed to be the cause of coronal mass ejections (CMEs), a major form of solar activity in the corona. The mechanisms for magnetic energy storage are crucial in understanding how a field may possess…

Astrophysics · Physics 2009-11-11 Mei Zhang , Natasha Flyer , Boon Chye Low

During solar minimum, the Sun is relatively inactive with few sunspots observed on the solar surface. Consequently, we observe a smaller number of highly energetic events such as solar flares or coronal mass ejections (CMEs), which are…

Solar and Stellar Astrophysics · Physics 2021-07-06 P. Bhowmik , A. R. Yeates

It is widely accepted that solar flares involve release of magnetic energy stored in the solar corona above an active region, but existing models do not include the explicitly time-dependent electrodynamics needed to describe such energy…

Solar and Stellar Astrophysics · Physics 2019-06-26 D. B. Melrose

Large scale dynamo-generated fields are a combination of interlocked poloidal and toroidal fields. Such fields possess magnetic helicity that needs to be regenerated and destroyed during each cycle. A number of numerical experiments now…

Astrophysics · Physics 2009-11-13 Axel Brandenburg

The global magnetic field in the solar corona is known to contain free magnetic energy and magnetic helicity above that of a current-free (potential) state. But the strength of this non-potentiality and its evolution over the solar cycle…

Solar and Stellar Astrophysics · Physics 2024-05-24 Anthony R. Yeates

This article broadly reviews our knowledge of solar flares. There is a particular focus on their global properties, as opposed to the microphysics such as that needed for magnetic reconnection or particle acceleration as such. Indeed solar…

Solar and Stellar Astrophysics · Physics 2011-08-18 Hugh S. Hudson

A model for the solar coronal magnetic field is proposed where multiple directed loops evolve in space and time. Loops injected at small scales are anchored by footpoints of opposite polarity moving randomly on a surface. Nearby footpoints…

Statistical Mechanics · Physics 2009-11-07 D. Hughes , M. Paczuski , R. O. Dendy , P. Helander , K. G. McClements

The processes governing energy storage and release in the Sun are both related to the solar magnetic field. We demonstrate the existence of a magnetic connection between energy released caused by a flare and increased oscillatory power in…

Solar and Stellar Astrophysics · Physics 2013-06-17 Aleksandra Andic , R. T. James McAteer

During eruptive solar flares and coronal mass ejections, a non-pot{\-}ential magnetic arcade with much excess magnetic energy goes unstable and reconnects. It produces a twisted erupting flux rope and leaves behind a sheared arcade of hot…

Solar and Stellar Astrophysics · Physics 2016-09-07 Eric Priest , Dana Longcope , Miho Janvier

Solar flares are intense bursts of electromagnetic radiation, which occur due to a rapid destabilization and reconnection of the magnetic field. While pre-flare signatures and trends have been investigated from magnetic observations prior…

Solar and Stellar Astrophysics · Physics 2025-06-18 Kara L. Kniezewski , Emily I. Mason , Daniel J. Emmons , Kyle E. Fitch , Seth H. Garland

Flares, sometimes accompanied by coronal mass ejections (CMEs), are the result of sudden changes in the magnetic field of stars with high energy release through magnetic reconnection, which can be observed across a wide range of the…

Solar active regions and the processes that occur in them have been extensively studied and analyzed and many types of models and characterizations have been proposed for the occurrence of different eruptive events that take place in the…

Solar and Stellar Astrophysics · Physics 2020-12-09 N. Granados Hernández , S. Vargas Domínguez

The energy released in solar flares derives from a reconfiguration of magnetic fields to a lower energy state, and is manifested in several forms, including bulk kinetic energy of the coronal mass ejection, acceleration of electrons and…

Solar and Stellar Astrophysics · Physics 2017-04-19 E. P. Kontar , J. E. Perez , L. K. Harra , A. A. Kuznetsov , A. G. Emslie , N. L. S. Jeffrey , N. H. Bian , B. R. Dennis

Solar flares are an abrupt release of magnetic energy in the Sun's atmosphere due to reconnection of the coronal magnetic field. This occurs in response to turbulent flows at the photosphere which twist the coronal field. Similar to…

Solar and Stellar Astrophysics · Physics 2018-06-06 Nastaran Farhang , Hossein Safari , Michael S. Wheatland

It is argued that much of the observed magnetic helicity losses at the solar surface may represent a reduction of an otherwise more dominant nonlinearity of solar and stellar dynamos. This nonlinearity is proportional to the internal twist…

Astrophysics · Physics 2007-05-23 A. Brandenburg , E. G. Blackman

Sunspots are concentrations of magnetic field visible on the solar surface (photosphere). It was considered implausible that solar flares, as resulted from magnetic reconnection in the tenuous corona, would cause a direct perturbation of…

Solar and Stellar Astrophysics · Physics 2017-05-12 Chang Liu , Yan Xu , Wenda Cao , Na Deng , Jeongwoo Lee , Hugh S. Hudson , Dale E. Gary , Jiasheng Wang , Ju Jing , Haimin Wang