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Related papers: Flare-productive active regions

200 papers

In this paper, we present a multi-wavelength analysis of an eruptive white-light M3.2 flare which occurred in active region NOAA 10486 on November 1, 2003. Excellent set of high resolution observations made by RHESSI and TRACE provide clear…

Solar and Stellar Astrophysics · Physics 2015-05-30 Bhuwan Joshi , Astrid M. Veronig , Jeongwoo Lee , Su-Chan Bong , Sanjiv K. Tiwari , Kyung-Suk Cho

The close connection of magnetic field structure on the one hand and observable features of complex ARs with high flare efficiency on the other one is investigated in frames of so-called dynamic classification of flaring magnetic…

Astrophysics · Physics 2007-05-23 R. N. Ikhsanov , Yu. V. Marushin

The abrupt and permanent changes of photospheric magnetic field in the localized regions of active regions during solar flares called magnetic imprints (MIs), have been observed for the past nearly three decades. The well known "coronal…

Solar and Stellar Astrophysics · Physics 2022-03-14 N. Vasantharaju , P. Vemareddy , B. Ravindra , V. H. Doddamani

Magnetic storms on stars manifest as remarkable, randomly occurring changes of the luminosity over durations that are tiny in comparison to the normal evolution of stars. These stellar flares are bursts of electromagnetic radiation from…

Solar and Stellar Astrophysics · Physics 2024-02-13 Adam F. Kowalski

Solar flares are explosive releases of magnetic energy. Hard X-ray (HXR) flare emission originates from both hot (millions of Kelvin) plasma and nonthermal accelerated particles, giving insight into flare energy release. The Nuclear…

An eruption event launched from solar active region (AR) NOAA 11719 is investigated based on coronal EUV observations and photospheric magnetic field measurements obtained from Solar Dynamic Observatory. The AR consists of a filament…

Solar and Stellar Astrophysics · Physics 2015-06-23 P. Vemareddy , J. Zhang

We compare the coronal magnetic energy and helicity of two solar active regions (ARs), prolific in major eruptive (AR~11158) and confined (AR~12192) flaring, and analyze the potential of deduced proxies to forecast upcoming flares. Based on…

Solar and Stellar Astrophysics · Physics 2020-01-08 J. K. Thalmann , K. Moraitis , L. Linan , E. Pariat , G. Valori , K. Dalmasse

RHESSI observations of a solar flare showing continuous motions of double hard X-ray sources interpreted as footpoints of magnetic loops are presented. The temporal evolution shows many distinct emission peaks of duration of some tens of…

Astrophysics · Physics 2009-11-11 Paolo C. Grigis , Arnold O. Benz

Magnetic flux ropes (MFRs) constitute the core structure of coronal mass ejections (CMEs), but hot debates remain on whether the MFR forms before or during solar eruptions. Furthermore, how flare reconnection shapes the erupting MFR is…

Solar and Stellar Astrophysics · Physics 2021-09-20 Chaowei Jiang , Jun Chen , Aiying Duan , Xinkai Bian , Xinyi Wang , Jiaying Li , Peng Zou , Xueshang Feng

The evolution of an X2.7 solar flare, that occurred in a complex $\beta\gamma\delta$ magnetic configuration region on 2003 November 3 is discussed utilizing a multi-wavelength data set. The very first signature of pre-flare coronal activity…

Astrophysics · Physics 2009-11-13 Bhuwan Joshi , P. K. Manoharan , Astrid M. Veronig , P. Pant , Kavita Pandey

In order to bridge the gap between heliospheric and solar observations of coronal mass ejections (CMEs), one of the key steps is to improve the understanding of their corresponding magnetic structures like the magnetic flux ropes (MFRs).…

Solar and Stellar Astrophysics · Physics 2022-08-03 Wen He , Qiang Hu , Chaowei Jiang , Jiong Qiu , Avijeet Prasad

During solar flares a tremendous amount of magnetic energy is released and transported through the Sun's atmosphere and out into the heliosphere. Despite over a century of study, many unresolved questions surrounding solar flares are still…

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

Shearing motion and magnetic flux cancellation around the polarity inversion line (PIL) play significant roles in the build-up of free magnetic energy and magnetic flux rope (MFR) in source region of major solar flares. Here we investigate…

Solar and Stellar Astrophysics · Physics 2026-05-12 Yijun Hou , Ting Li , Shuhong Yang , Leping Li , Yingjie Cai , Xiaofeng Liu , Shuo Yang , Yilin Guo , Shihao Rao , Chuan Li , Guiping Zhou

The question of the nature of precursors of solar flares, as well as their relationship with subsequent flares, still has no unambiguous answer. This is due, in particular, to the lack of systematic statistical work, the relative…

Solar and Stellar Astrophysics · Physics 2025-05-15 G. G. Motorina , I. N. Sharykin , I. V. Zimovets , A. S. Motorin

Erupting flux ropes play crucial role in powering a wide range of solar transients, including flares, jets, and coronal mass ejections. These events are driven by the release of stored magnetic energy, facilitated by the shear in the…

Solar and Stellar Astrophysics · Physics 2025-11-19 Samrat Sen , Sushree S Nayak , Patrick Antolin

Plasma loops are the elementary structures of solar flaring active regions which dominate the whole processes of flaring eruptions. The standard flare models are well explained the evolution and eruption after magnetic reconnection around…

Solar and Stellar Astrophysics · Physics 2021-10-18 Baolin Tan

Solar flares are driven by release of free magnetic energy and often associated with restructurization of the magnetic field topology. Yet, observations of evolving magnetic field in the flaring volume are limited to very few cases…

Solar and Stellar Astrophysics · Physics 2026-02-18 Gregory D. Fleishman , Tatyana Kaltman , Sijie Yu

Solar active regions are driven dissipative dynamical systems. The turbulent convection zone forces new magnetic flux tubes to rise above the photosphere and shuffles the magnetic fields which are already above the photosphere. The driven…

Astrophysics · Physics 2009-09-29 Loukas Vlahos

During 2017, when the Sun was moving toward the minimum phase of solar cycle 24, an exceptionally eruptive active region (AR) NOAA 12673 emerged on the Sun during August 28-September 10. During the highest activity level, the AR turned into…

Solar and Stellar Astrophysics · Physics 2022-12-22 Bhuwan Joshi , Prabir K. Mitra

Arcades of flare loops form as a consequence of magnetic reconnection powering solar flares and eruptions. We analyse the morphology and evolution of flare arcades that formed during five well-known eruptive flares. We show that the arcades…

Solar and Stellar Astrophysics · Physics 2021-03-24 Juraj Lörinčík , Jaroslav Dudík , Guillaume Aulanier