A Long-Duration Solar Flare with Mass Ejection and Global Consequences

1996 ◽  
Vol 470 ◽  
pp. 629 ◽  
Author(s):  
H. S. Hudson ◽  
L. W. Acton ◽  
S. L. Freeland
2014 ◽  
Vol 4 (2) ◽  
pp. 555-564
Author(s):  
A.M Aslam

On September 24, 2011 a solar flare of M 7.1 class was released from the Sun. The flare was observed by most of the space and ground based observatories in various wavebands. We have carried out a study of this flare to understand its causes on Sun and impact on earth. The flare was released from NOAA active region AR 11302 at 12:33 UT. Although the region had already produced many M class flares and one X- class flare before this flare, the magnetic configuration was not relaxed and still continued to evolve as seen from HMI observations. From the Solar Dynamics Observatory (SDO) multi-wavelength (131 Ã…, 171 Ã…, 304 Ã… and 1600Ã…) observations we identified that a rapidly rising flux rope triggered the flare although HMI observations revealed that magnetic configuration did not undergo a much pronounced change. The flare was associated with a halo Coronal Mass Ejection (CME) as recorded by LASCO/SOHO Observations. The flare associated CME was effective in causing an intense geomagnetic storm with minimum Dst index -103 nT. A radio burst of type II was also recorded by the WAVES/WIND. In the present study attempt is made to study the nature of coupling between solar transients and geospace.


Author(s):  
Hugh S. Hudson

The Carrington event in 1859, a solar flare with an associated geomagnetic storm, has served as a prototype of possible superflare occurrence on the Sun. Recent geophysical (14C signatures in tree rings) and precise time-series photometry [the bolometric total solar irradiance (TSI) for the Sun, and the broadband photometry from Kepler and Transiting Exoplanet Survey Satellite, for the stars] have broadened our perspective on extreme events and the threats that they pose for Earth and for Earth-like exoplanets. This review assesses the mutual solar and/or stellar lessons learned and the status of our theoretical understanding of the new data, both stellar and solar, as they relate to the physics of the Carrington event. The discussion includes the event's implied coronal mass ejection, its potential “solar cosmic ray” production, and the observed geomagnetic disturbances based on the multimessenger information already available in that era. Taking the Carrington event as an exemplar of the most extreme solar event, and in the context of our rich modern knowledge of solar flare and/or coronal mass ejection events, we discuss the aspects of these processes that might be relevant to activity on solar-type stars, and in particular their superflares. ▪ The Carrington flare of 1859, though powerful, did not significantly exceed the magnitudes of the greatest events observed in the modern era. ▪ Stellar “superflare” events on solar-type stars may share common paradigms, and also suggest the possibility of a more extreme solar event at some time in the future. ▪ We benefit from comparing the better-known microphysics of solar flares and CMEs with the diversity of related stellar phenomena. Expected final online publication date for the Annual Review of Astronomy and Astrophysics, Volume 59 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


2008 ◽  
Vol 4 (S259) ◽  
pp. 123-124
Author(s):  
Youhei Masada

AbstractWe construct a magnetic reconnection model for magnetar giant flare in the framework of solar flare/coronal mass ejection theory. As is the case with the solar flare, the explosive magnetic reconnection plays a crucial role in the energetics of the magnetar flare. A key physics controlling the energy transport in the system, on the other hand, is the radiative process unlike that in the solar flare. After the release of the magnetic energy via the magnetic reconnection, the radiative heat flux drives the baryonic evaporation. Our model can predict that the baryonic matter evaporated in the preflare stage would be the origin of the radio emitting ejecta observed in association with the giant flare on 2004 December 27 from SGR1806-20.


1980 ◽  
Vol 91 ◽  
pp. 223-226
Author(s):  
S. S. Degaonkar ◽  
H. S. Sawant ◽  
R. V. Bhonsle

An interesting microwave event at 2800 MHz was recorded at Ahmedabad on September 19, 1977 at 1026 UT at the same time as the H-Alpha solar flare of importance 3B. The microwave burst was of impulsive nature, with as many as twenty impulses in seventy minutes with a quasi-periodicity of 1 to 5 minutes. An X-ray burst recorded by GOES Satellite in 1-8A band showed at the same time a smooth soft X-ray profile with apparently no sign of hard X-ray bursts. This indicates that the acceleration of discrete electron streams which produced impulsive microwave bursts was not sufficient to produce the hard X-ray component but got thermalised to produce soft X-ray emission, with a gradual rise and a slow decay covering a long duration of more than 2 1/2 hours.


2001 ◽  
Vol 203 ◽  
pp. 344-346
Author(s):  
T. Yokoyama ◽  
K. Akita ◽  
T. Morimoto ◽  
K. Inoue ◽  
J. Newmark

We find an important piece of evidence for magnetic reconnection inflow in a flare on March 18, 1999. The flare occurred on the north-east limb, displaying a nice cusp-shaped soft X-ray loop and a plasmoid ejection typical for the long-duration-events. As the plasmoid is ejected, magnetic reconnection occurs at the disconnecting point. A clear ingoing pattern toward the magnetic X-point is seen. The velocity of this apparent motion is about 5 km sec−1, which is an upper limit on reconnection inflow speed. Based on this observation, we derive the reconnection rate as MA = 0.001 − 0.03, where MA is a Alfvén Mach number of the inflow.


Solar Physics ◽  
2012 ◽  
Vol 279 (2) ◽  
pp. 465-475 ◽  
Author(s):  
Pierre Kaufmann ◽  
Gordon D. Holman ◽  
Yang Su ◽  
C. Guillermo Gimenez de Castro ◽  
Emilia Correia ◽  
...  

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