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Vertical Dynamics of the Energy Release Process in a Simple two-Ribbon Flare
Warmuth, Alexander; Otruba, Wolfgang; Klein, Karl-Ludwig +2 more
Observations of the quiescent filament eruption and the spotless two-ribbon flare of 12 September 2000 are presented. A simple flare morphology, large spatial scales, and a suitable viewing angle provide insight into characteristics of the energy release process which is attributed to the reconnection process in the current sheet formed below the …
Statistical Characteristics of CMEs and Flares Associated with Solar Type II Radio Bursts
Moon, Y. -J.; Shanmugaraju, A.; Dryer, M. +1 more
We have made a comprehensive statistical study of the characteristics of 290 SOHO/LASCO CMEs and their associated GOES-8 X-ray flares (> C1 class) during the period January 1997-December 2000 of solar cycle 23's rise to maximum. These events were classified into mainly three groups (Group noII - not associated with type IIs, Group II - associat…
Interaction and Dynamics of the Photospheric Network Magnetic Elements
Tarbell, T. D.; Shine, R.; Ryutova, M.
Small-scale magnetic elements in the quiet photospheric network are believed to play a key role in the energy flow from the solar surface to upper layers of atmosphere. Their intense hydro-magnetic activity includes merging and fragmentation of same polarity fluxes, `total' or partial cancellation of neighboring flux elements of opposite polarity,…
Themis, BBSO, MDI and trace observations of a filament eruption
Romano, P.; Yurchyshyn, V. B.; Contarino, L. +1 more
We describe a filament destabilization which occurred on 5 May 2001 in NOAA AR 9445, before a flare event. The analysis is based on Hα data acquired by THEMIS operating in IPM mode, Hα data and magnetograms obtained at the Big Bear Solar Observatory, MDI magnetograms and 171 Å images taken by TRACE. Observations at 171 Å show that ∼ 2.5 hours befo…
Measurements of Flux Cancellation During Filament Formation
Wood, Paul; Martens, Piet
We study the process of flux cancellation and filament formation in a nest of three decaying active regions, using data from SOHO MDI and EIT, and Hα images from Meudon and Big Bear. We find that there are no apparent EUV loops connecting the two poles of a cancelling feature prior to and during cancellation, suggesting an absence of coronal magne…
Coronal Magnetic Field Context of Simple CMEs Inferred from Global Potential Field Models
Luhmann, J. G.; Yashiro, Seiji; Zhao, Xuepu +1 more
Most work on coronal mass ejection (CME) interpretation focuses on the involved active region rather than on the large-scale coronal context. In this paper a global potential-field source-surface model of the coronal magnetic field is used to evaluate the sensitivity of the coronal field configuration to the location, orientation, and strength of …
Flare-Induced Excitation of Solar p modes
Basu, Sarbani; Antia, H. M.; Ambastha, Ashok
Solar flares release large amounts of energy at different layers of the solar atmosphere, including at the photosphere in the case of exceptionally major events. Therefore, it is expected that large flares would be able to excite acoustic waves on the solar surface, thereby affecting the p-mode oscillation characteristics. We have applied the ring…
Impulses of activity and the Solar cycle
Benevolenskaya, Elena E.
Extreme-ultraviolet data from EIT/SOHO (1996-2002), soft X-ray data from Yohkoh (1991-2001), and magnetic field data from MDI/SOHO (1996-2002) and Kitt Peak Observatory, NSO/NOAO (1991-2002) are analyzed together in the form of synoptic maps for the investigation of solar cycle variations of the corona and their relation to the magnetic field. The…
ICME Identification from Solar Wind Ion Measurements
Russell, C. T.; Shinde, A. A.
Interplanetary coronal mass ejections (ICMEs), the interplanetary counterpart of coronal mass ejections (CMEs), are most commonly identified by their enhanced magnetic field strengths and rotating magnetic field orientation. However, there are other frequent signatures in the plasma. We use a pair of these signatures, a linearly decreasing plasma …
Energetic Particles and Coronal Mass Ejections: a Case Study From ace and Ulysses
Simnett, G. M.
In 2001 the Ulysses spacecraft crossed the ecliptic plane near perihelion. The heliographic longitude with respect to the Earth was within ± 20° of the west solar limb while it was ± 15° of the ecliptic plane, which meant that coronal mass ejections seen off the solar west limb were likely to pass over Ulysses. On 10 May the largest > 38 keV el…