English
Related papers

Related papers: Continuum enhancements, line profiles and magnetic…

200 papers

The first X-class flare of the current solar cycle 24 occurred in Active Region NOAA 11158 during its central meridian passage on 2011 February 15. This two ribbon white-light flare was well observed by the Helioseismic and Magnetic Imager…

Solar and Stellar Astrophysics · Physics 2015-05-28 R. A. Maurya , P. Vemareddy , A. Ambastha

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 presence of current sheet instabilities, such as the tearing mode instability, are needed to account for the observed rate of energy release in solar flares. Insights into these current sheet dynamics can be revealed by the behaviour of…

Solar and Stellar Astrophysics · Physics 2021-12-08 Ryan J. French , Sarah A. Matthews , I. Jonathan Rae , Andrew W. Smith

Solar flares are known to generate seismic waves in the Sun. We present a detailed analysis of seismic emission in sunspots accompanying M- and X-class solar flares. For this purpose, we have used high-resolution Dopplergrams and…

Solar and Stellar Astrophysics · Physics 2020-07-13 Hirdesh Kumar , Brajesh Kumar

We investigate the plasma and magnetic environment of active region NOAA 11261 on 2 August 2011 around a GOES M1.4 flare/CME (SOL2011-08-02T06:19). We compare coronal emission at (extreme) ultraviolet and X-ray wavelengths, using SDO AIA…

Solar and Stellar Astrophysics · Physics 2016-08-03 Julia K. Thalmann , Astrid M. Veronig , Yang Su

Solar flares are sudden and violent releases of magnetic energy in the solar atmosphere that can be divided in eruptive flares, when plasma is ejected from the solar atmosphere, resulting in a coronal mass ejection (CME), and confined…

Solar and Stellar Astrophysics · Physics 2017-05-24 F. P. Zuccarello , R. Chandra , B. Schmieder , G. Aulanier , R. Joshi

We studied the dynamics of the solar atmosphere in the region of a large quiet-Sun filament, which erupted on 21 October 2010. The filament eruption started at its northern end and disappeared from the H$\alpha$ line-core filtergrams line…

Solar and Stellar Astrophysics · Physics 2020-04-29 Jiří Wollmann , Michal Švanda , David Korda , Thierry Roudier

Active region (AR) 12673 produced many M-class and several X-class flares, one of which being an X9.3 flare, which is recorded as the largest solar flare in solar cycle 24. We studied the evolution of the three-dimensional flare-productive…

Solar and Stellar Astrophysics · Physics 2021-02-24 Daiki Yamasaki , Satoshi Inoue , Shin'ichi Nagata , Kiyoshi Ichimoto

Using the H$\alpha$ data from the New Vacuum Solar Telescope (NVST) at the Fuxian Solar Observatory together with multi-wavelength images and magnetograms obtained by Solar Dynamics Observatory (SDO), we study the detailed process of three…

Solar and Stellar Astrophysics · Physics 2020-01-08 Guorong Chen , Xiaoli Yan

We analyze the spatial and temporal variations of the abrupt photospheric magnetic changes associated with six major flares using 12-minute, 0.5-arcsec vector magnetograms from NASA's Helioseismic and Magnetic Imager instrument (HMI) on the…

Solar and Stellar Astrophysics · Physics 2012-11-12 Gordon Petrie

We present simultaneous photospheric and chromospheric observations of the trailing sunspot in NOAA 10904 during a weak flare eruption (GOES magnitude B7.8), obtained with the Swedish Solar Telescope (SST) in La Palma, Canary Islands.…

Solar and Stellar Astrophysics · Physics 2009-08-27 J. Hirzberger , T. Riethm\" uller , A. Lagg , S. K. Solanki , P. Kobel

Predicting the severity of the solar eruptive phenomena like flares and Coronal Mass Ejections (CMEs) remains a great challenge despite concerted efforts for several decades. The advent of high quality vector magnetograms obtained from…

Solar and Stellar Astrophysics · Physics 2015-05-19 Sanjiv Kumar Tiwari , P. Venkatakrishnan , Sanjay Gosain

The dynamic properties of flare ribbons and the often associated filament eruptions can provide crucial information on the flaring coronal magnetic field. This Letter analyzes the GOES-class X1.0 flare on 2014 March 29…

Solar and Stellar Astrophysics · Physics 2015-10-21 Chang Liu , Na Deng , Rui Liu , Jeongwoo Lee , Etienne Pariat , Thomas Wiegelmann , Yang Liu , Lucia Kleint , Haimin Wang

We report multi-wavelength study of a complex M-class solar eruptive flare that consists of three different sets of flare ribbons, viz. circular, parallel, and remote ribbons. Magnetic field modeling of source active region NOAA 12242…

Solar and Stellar Astrophysics · Physics 2021-01-26 Navin Chandra Joshi , Bhuwan Joshi , Prabir K. Mitra

Observations of the Sun with the Atacama Large Millimeter Array have now started, and the thermal infrared will regularly be accessible from the NSF's Daniel K. Inouye Solar Telescope. Motivated by the prospect of these new data, and by…

Solar and Stellar Astrophysics · Physics 2017-09-20 Paulo J. A. Simões , Graham S. Kerr , Lyndsay Fletcher , Hugh S. Hudson , C. Guillermo Giménez de Castro , Matt Penn

State-of-the-art solar instrumentation is revealing magnetic activity of the Sun with unprecedented resolution. Observations with the 1.6m New Solar Telescope of the Big Bear Solar Observatory are making next steps in our understanding of…

Solar and Stellar Astrophysics · Physics 2015-06-19 Santiago Vargas Dominguez , Alexander Kosovichev , Vasyl Yurchyshyn

Magnetic flux emergence and decay in the Sun span from days to months. However, their tracking is typically limited to about half a solar rotation when relying on single-vantage-point observations. Combining observations from both the…

Solar and Stellar Astrophysics · Physics 2026-01-14 I. Kontogiannis , Y. Zhu , K. Barczynski , M. Z. Stiefel , H. Collier , J. McKevitt , J. S. Castellanos Durán , S. Berdyugina , L. K. Harra

Solar flares and coronal mass ejections (CMEs), especially the larger ones, emanate from active regions (ARs). With the aim to understand the magnetic properties that govern such flares and eruptions, we systematically survey all flare…

Solar and Stellar Astrophysics · Physics 2017-01-11 Shin Toriumi , Carolus J. Schrijver , Louise K. Harra , Hugh Hudson , Kaori Nagashima

We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the pre-existing field of active…

Solar and Stellar Astrophysics · Physics 2018-04-18 Salvo L. Guglielmino , Francesca Zuccarello , Peter R. Young , Mariariata Murabito , Paolo Romano

In this article, we study the origin of precursor flare activity and investigate its role towards triggering the eruption of a flux rope which resulted into a dual-peak M-class flare (SOL2015-06-21T02:36) in the active region NOAA 12371.…

Solar and Stellar Astrophysics · Physics 2020-03-11 Prabir K. Mitra , Bhuwan Joshi , Avijeet Prasad