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The rotation of erupting filaments in the solar corona is addressed through a parametric simulation study of unstable, rotating flux ropes in bipolar force-free initial equilibrium. The Lorentz force due to the external shear field…

Solar and Stellar Astrophysics · Physics 2015-06-03 B. Kliem , T. Török , W. T. Thompson

Sunspots are regions of decreased brightness on the visible surface of the Sun (photosphere) that are associated with strong magnetic fields. They have been found to be locations associated with solar flares, which occur when energy stored…

Solar and Stellar Astrophysics · Physics 2013-01-24 Sophie A. Murray

Solar active regions (ARs) that produce strong flares and coronal mass ejections (CMEs) are known to have a relatively high non-potentiality and are characterized by delta-sunspots and sheared magnetic structures. In this study, we conduct…

Solar and Stellar Astrophysics · Physics 2017-11-29 Shin Toriumi , Shinsuke Takasao

The magnetic breakout model, in which reconnection in the corona leads to destabilization of a filament channel, explains numerous features of eruptive solar events, from small-scale jets to global-scale coronal mass ejections (CMEs). The…

Solar and Stellar Astrophysics · Physics 2021-03-17 Pankaj Kumar , Judith T. Karpen , Spiro K. Antiochos , Peter F. Wyper , C. Richard DeVore , Benjamin J. Lynch

Flares and CMEs can have deleterious effects on their surroundings: they can erode atmospheres of orbiting planets over time and also have high importance in stellar evolution. Most of the CME detections in the literature are single events…

An unexpected strong geomagnetic storm occurred on 2018 August 26, which was caused by a slow coronal mass ejection (CME) from a gradual eruption of a large quiet-region filament. We investigate the eruption and propagation characteristics…

Solar and Stellar Astrophysics · Physics 2019-11-06 Chong Chen , Ying D. Liu , Rui Wang , Xiaowei Zhao , Huidong Hu , Bei Zhu

Solar flares (SFs) are sudden brightening observed over the Sun surface which is associated with a large energy release. Flares with burst of Xray emission are normally followed by a mass ejection of electrons and ions from the solar…

Solar and Stellar Astrophysics · Physics 2022-02-03 Kamsali Nagaraja , Praveen Kumar Basuvaraj , S. C. Chakravarty

Shear flows have been prescribed in numerical models of coronal mass ejections and flares for decades as a way of energizing magnetic fields to erupt. While such shear flows have long been observed in the solar atmosphere, until recently,…

Astrophysics · Physics 2008-12-19 Ward B. Manchester

We analyse in this work the propagation and geoeffectiveness of four successive coronal mass ejections (CMEs) that erupted from the Sun during 21--23 May 2013 and that were detected in interplanetary space by the Wind and/or STEREO-A…

An update of Owens et al. (2008) shows that the relationship between the coronal mass ejection (CME) rate and the heliospheric magnetic field strength predicts a field floor of less than 4 nT at 1 AU. This implies that the record low values…

Solar and Stellar Astrophysics · Physics 2010-04-14 N. U. Crooker , M. J. Owens

The rise of flux-tubes with intense magnetic fields from the base of the convection zone to the solar surface has been substantiated as a probable mechanism for sunspot formation. The origin of flux-tubes of sufficient strength (~10^5 G) is…

Solar and Stellar Astrophysics · Physics 2020-05-06 Leonid Kitchatinov

Solar flares are often accompanied by filament/prominence eruptions ($\sim10^{4}$ K and $\sim 10^{10-11}$ cm$^{-3}$), sometimes leading to coronal mass ejections (CMEs) that directly affect the Earth's environment. `Superflares' are found…

Recent Solar Dynamic Observatory observations reveal that coronal mass ejections (CMEs) consist of a multi-temperature structure: a hot flux rope and a cool leading front (LF). The flux rope first appears as a twisted hot channel in the…

Solar and Stellar Astrophysics · Physics 2015-06-12 X. Cheng , J. Zhang , D. M. Ding , Y. Liu , W. Poomvises

Coronal mass ejections (CMEs) are often associated with X-ray (SXR) flares powered by magnetic reconnection in the low-corona, while the CME shocks in the upper corona and interplanetary (IP) space accelerate electrons often producing the…

Solar and Stellar Astrophysics · Physics 2024-11-06 Atul Mohan , Natchimuthuk Gopalswamy , Hemapriya Raju , Sachiko Akiyama

Classical T Tauri stars (CTTSs) are young low-mass stellar objects accreting mass from their circumstellar disks. They are characterized by high levels of coronal activity as revealed by X-ray observations. This activity may affect the disk…

We investigated a set of 54 interplanetary coronal mass ejection (ICME) events whose solar sources are very close to the disk center (within 15 degrees from the central meridian). The ICMEs consisted of 23 magnetic cloud (MC) events and 31…

Solar and Stellar Astrophysics · Physics 2015-06-12 N. Gopalswamy , P. MÄkelÄ , S. Akiyama , H. Xie , S. Yashiro , A. A. Reinard

Of all the activity observed on the Sun, two of the most energetic events are flares and Coronal Mass Ejections (CMEs). Usually, solar active regions that produce large flares will also produce a CME, but this is not always true (Yashiro et…

Solar and Stellar Astrophysics · Physics 2016-04-25 Monica G. Bobra , Stathis Ilonidis

Interest in stealth coronal mass ejections (CMEs) is increasing due to their relatively high occurrence rate and space weather impact. However, typical CME signatures such as extreme-ultraviolet dimmings and post-eruptive arcades are hard…

With the aim of understanding how the magnetic properties of active regions (ARs) control the eruptive character of solar flares, we analyze 719 flares of Geostationary Operational Environmental Satellite (GOES) class $\geq$C5.0 during…

Solar and Stellar Astrophysics · Physics 2021-09-01 Ting Li , Anqin Chen , Yijun Hou , Astrid M. Veronig , Shuhong Yang , Jun Zhang

Triggering process for prominence instability and consequent CMEs is not fully understood. Prominences are maintained by the Lorentz force against the gravity, therefore reduction of the prominence mass due to the coronal rain may cause the…

Solar and Stellar Astrophysics · Physics 2022-01-26 Z. Vashalomidze , T. V. Zaqarashvili , V. Kukhianidze , G. Ramishvili , A. Hanslmeier , P. Gomory