bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successive filament eruptions within one solar breakout event
Authors: Shen Yuandeng 
Published: January 2014

AbstractThe magnetic breakout model has been widely used to explain solar eruptive activities. Here, we apply it to explain successive filament eruptions occurred in a quadrupolar magnetic source region. Based on the high temporal and spatial resolution, multi-wavelengths observations taken by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO), we find some signatures that support the occurrence of breakout-like external reconnection just before the start of the successive filament eruptions. Furthermore, the extrapolated three-dimensional coronal field also reveals that the magnetic topology above the quadrupolar source region resembles that of the breakout model. We propose a possible mechanism within the framework of the breakout model to interpret the successive filament eruptions, in which the so-called magnetic implosion mechanism is firstly introduced to be the physical linkage of successive filament eruptions. We conclude that the structural properties of coronal fields are important for producing successive filament eruptions.
Flux rope axis geometry of magnetic clouds deduced from in situ data
Authors: Janvier Miho , Démoulin Pascal , Dasso Sergio 
Published: January 2014

AbstractMagnetic clouds (MCs) consist of flux ropes that are ejected from the low solar corona during eruptive flares. Following their ejection, they propagate in the interplanetary medium where they can be detected by in situ instruments and heliospheric imagers onboard spacecraft. Although in situ measurements give a wide range of data, these only depict the nature of the MC along the unidirectional trajectory crossing of a spacecraft. As such, direct 3D measurements of MC characteristics are impossible. From a statistical analysis of a wide range of MCs detected at 1 AU by the Wind spacecraft, we propose different methods to deduce the most probable magnetic cloud axis shape. These methods include the comparison of synthetic distributions with observed distributions of the axis orientation, as well as the direct integration of observed probability distribution to deduce the global MC axis shape. The overall shape given by those two methods is then compared with 2D heliospheric images of a propagating MC and we find similar geometrical features.
Reconstruction of magnetic clouds from in-situ spacecraft measurements and intercomparison with their solar sources
Authors: Hu Qiang , Qiu Jiong 
Published: January 2014

AbstractCoronal Mass Ejections (CMEs) are eruptive events that originate, propagate away from the Sun, and carry along solar material with embedded solar magnetic field. Some are accompanied by prominence eruptions. A subset of the interplanetary counterparts of CMEs (ICMEs), so-called Magnetic Clouds (MCs) can be characterized by magnetic flux-rope structures. We apply the Grad-Shafranov (GS) reconstruction technique to examine the configuration of MCs and to derive relevant physical quantities, such as magnetic flux content, relative magnetic helicity, and the field-line twist, etc. Both observational analyses of solar source region characteristics including flaring and associated magnetic reconnection process, and the corresponding MC structures were carried out. We summarize the main properties of selected events with and without associated prominence eruptions. In particular, we show the field-line twist distribution and the intercomparison of magnetic flux for these flux-rope structures.
Properties and processes that influence CME geo-effectiveness
Authors: Lavraud Benoit , Rouillard Alexis 
Published: January 2014

AbstractThe geo-effectiveness of coronal mass ejections (CME) is determined by a complex chain of processes. This paper highlights this fact by first discussing the importance of CMEs intrinsic properties set at the Sun (e.g., trajectory, eruption process, orientation, etc.). We then review other key processes that may occur during propagation (e.g., shocks, compressions, magnetic flux erosion) and in the specific interaction with Earth's magnetosphere (e.g., magnetic properties, preconditioning mechanisms). These processes sequentially have a significant influence on the final geo-effectiveness of CMEs. Their relative importance is discussed. While the CME's trajectory, magnetic field orientation, velocity and their duration as set at the Sun certainly are key ingredients to geo-effectiveness, other processes and properties, that at first appear secondary, often may be as important.
Clarifying some issues on the geoeffectiveness of limb halo CMEs
Authors: Cid Consuelo , Cremades Hebe , Aran Angels , Mandrini Cristina , Sanahuja Blai , Schmieder Brigitte , Menvielle Michel , Rodriguez Luciano , Saiz Elena , Cerrato Yolanda , Dasso Sergio , Jacobs Carla , Lathuillere Chantal , Zhukov Andrei 
Published: January 2014

AbstractA recent study by Cid et al. (2012) showed that full halo coronal mass ejections (CMEs) coming from the limb can disturb the terrestrial environment. Although this result seems to rise some controversies with the well established theories, the fact is that the study encourages the scientific community to perform careful multidisciplinary analysis along the Sun-to-Earth chain to fully understand which are the solar triggers of terrestrial disturbances. This paper aims to clarify some of the polemical issues arisen by that paper.
Coronal Mass Ejections and Angular Momentum Loss in Young Stars
Authors: Aarnio Alicia N. , Stassun Keivan G. , Matt Sean P. 
Published: January 2014

AbstractIn our own solar system, the necessity of understanding space weather is readily evident. Fortunately for Earth, our nearest stellar neighbor is relatively quiet, exhibiting activity levels several orders of magnitude lower than young, solar-type stars. In protoplanetary systems, stellar magnetic phenomena observed are analogous to the solar case, but dramatically enhanced on all physical scales: bigger, more energetic, more frequent. While coronal mass ejections (CMEs) could play a significant role in the evolution of protoplanets, they could also affect the evolution of the central star itself. To assess the consequences of prominence eruption/CMEs, we have invoked the solar-stellar connection to estimate, for young, solar-type stars, how frequently stellar CMEs may occur and their attendant mass and angular momentum loss rates. We will demonstrate the necessary conditions under which CMEs could slow stellar rotation.
Magnetised winds of low-mass stars and their impact on exoplanets
Authors: Vidotto A. A. 
Published: January 2014

AbstractThe proper characterisation of stellar winds is crucial to constrain interactions between exoplanets and their surrounding environments and also essential for the study of space weather events on exoplanets. Although the great majority of exoplanets discovered so far are orbiting cool, low-mass stars with properties (mass, radius and effective temperatures) similar to solar, the stellar magnetism can be significantly different from the solar one, both in topology and intensity. Due to the current technology used in exoplanetary searches, most of the currently known exoplanets are found orbiting at extremely close distances to their host stars (< 0.1 au). The dramatic differences in stellar magnetism and orbital radius can make the interplanetary medium of exoplanetary systems remarkably distinct from the one present in the solar system. In addition, the interaction of the stellar winds with exoplanets can lead, among others, to observable signatures that are absent in our own solar system.
Observations of Overlying Extreme-ultraviolet Arches confining the eruption of a Filament
Authors: Chen Huadong , Ma Suli , Zhang Jun 
Published: January 2014

AbstractUsing the multi-wavelength data from AIA/SDO, we report a failed filament eruption, which was associated with an X1.9 flare, but without any distinct CME, coronal dimming or EUV wave. Some magnetic arches above the filament was observed distinctly in EUV channels, especially in 94 Å and 131 Å, before and during the filament eruption. Our results show that the overlying arcades expanded along with the ascent of the filament at first until they reached a projected height of about 49 Mm above the Suns surface, where they stopped. The following filament material was observed to be confined by the stopped EUV arches and not to escape from the Sun. These results support that the overlying arcades play an important role in preventing the filament to erupt outward successfully.
Filament Connectivity and “Reconnection”
Authors: Filippov Boris 
Published: January 2014

AbstractStable long lived solar filaments during their lives can approach each other, merge, and form circular structures. Since filaments follow large scale polarity inversion lines of the photospheric magnetic field, their evolution reflects changes of the photospheric field distribution. On the other hand, filament interaction depends on their internal magnetic structure reviled in particular by filament chirality. Possibility of magnetic field line reconnection of neighbor filaments is discussed. Many examples of connectivity changes in a course of photospheric field evolution were found in our analysis of daily Hα filtergrams for the period of maximum activity of the solar cycle 23.
3D dynamical structuring of a high latitude erupting prominence: I- Analysis of the cool plasma flows before the eruption
Authors: Koutchmy Serge , Filippov Boris , Tavabi Ehsan , Bazin Cyril , Weiller Sylvain 
Published: January 2014

AbstractBoth the origin of the quiescent prominences and their eruption related to CMEs are still a matter of extended studies. The small scale dynamic aspects like vortex structures and counter- flows are now seriously taken into account having in mind that the flows are a good proxy of the line of force of the omnipresent but rather unknown in detail force free or not magnetic field. Large scale vortex has been detected in a high latitude prominence observed on November 13- 14, 2011 before its eruption.
On 2D Linear Polarimetry in Prominences
Authors: Popov V. V. , Kim I. S. , Suyunova E. Z. 
Published: January 2014

AbstractAn approach for high-precision 2D linear polarimetry is briefly described. The key components are reducing random errors, reducing systematic errors, and obtaining 2D distributions of the linear polarization degree, p, and polarization angle, χ (deviation of the polarization plane from the direction tangential to the solar limb).
Spectroscopic measurements of EUV ejecta in a CME: a high-blueshift trailing thread
Authors: Williams David , Baker Deborah , van Driel-Gesztelyi Lidia , Green Lucie 
Published: January 2014

AbstractThe mass of erupting prominence material can be inferred from the obscuration of emission behind this mass of cool plasma thanks to the rapid cadence of SDO/AIA images in the short EUV wavelength range (Carlyle et al. 2013, these proceedings). In comparing this approach with spectral observations from Hinode/EIS, to monitor contributions from emission seen around the erupting prominence material, we have found an intriguing component of blue-shifted emission, trailing the erupting prominence, with Doppler shifts on the order of 350 km s−1 in bright lines of both He ii and Fe xii.
Simulation of sigmoid structure and filament eruption of AR11283 using a three-dimensional data-driven magnetohydrodynamic model
Authors: Wu S. T. , Jiang Chaowei , Feng Xueshang , Hu Qiang , Liu Yang 
Published: January 2014

AbstractThis paper describes an MHD simulation of an observed Sigmoid in AR 11283 from its formation to eruption. The Non-linear Force Free MHD model (Jiang and Feng, 2012) and the data-driven active region evolution model (Wu et al., 2006; Jiang et al. 2013) together with the SDO/HMI magnetograms are used. We show the successful simulation results of the eruption of a flux-rope structure.
Galactic cosmic ray decreases associated with non-interacting magnetic clouds in the 23rd solar cycle
Authors: Masías-Meza J. J. , Dasso S. 
Published: January 2014

AbstractSudden Galactic Cosmic Ray (GCR) intensity decreases are related to the passage of Interplanetary Coronal Mass Ejections (ICMEs). These phenomena are also known as Forbush Decreases (FDs). The deepest FDs are associated with the passage of Magnetic Clouds (MCs). In this preliminary study we select “non-interacting” MCs associated with FDs observed from ground Neutron Monitors in the period 1996-2009, with the aim of reducing the complexity and the number of parameters involved in the GCR-MC interactions. We introduce a method to determine properties of the “ejecta component” of the FD. We analyze properties of the ejecta component in combination with properties of MCs. From the resulting selection of events, we find that those FDs containing ejecta components show stronger correlations with MC parameters than our total sample of events.
Statistical relationship between CME speed and soft X-ray peak flux of the associated flare during solar cycle 23
Authors: Salas-Matamoros C. , Klein K.-L. , Taliashvili L. 
Published: January 2014

AbstractThe relationship between the speed of coronal mass ejections and the peak soft X-ray flux of the associated flares is studied for events occurring near the solar limbs between 1996 and 2008. An improved, though still moderate, correlation between the two parameters is found.
Recurrent filament eruptions and associated CMEs
Authors: Schmieder Brigitte , Cremades Hebe , Mandrini Cristina , Démoulin Pascal , Guo Yang 
Published: January 2014

AbstractWe investigate the violent events in the cluster of two active regions (ARs), NOAA numbers 11121 and 11123, observed on 11 November 2010 by the Solar Dynamics Observatory (SDO). Within one day the magnetic field intensity increased by 70% with the emergence of new groups of bipoles in AR 11123, where three filaments are seen along the complex inversion line. The destabilization of the filaments led to flares and CMEs. The CMEs around 08:24 UT and 17:00 UT are directly related to the partial eruption of one filament in the new AR, as shown by a topology computation and analysis. The other CMEs on this day are due to either other ARs or to the destabilization of the global magnetic configuration of the two ARs. This conclusion can be only reached by using the three eyes of SOHO, STEREO and SDO.
Role of filament plasma remnants in ICMEs leading to geomagnetic storms
Authors: Sharma Rahul , Srivastava Nandita , Chakrabarty D. 
Published: January 2014

AbstractWe studied three interplanetary coronal mass ejections associated with solar eruptive filaments. Filament plasma remnants embedded in these structures were identified using plasma, magnetic and compositional signatures. These features when impacted the Earth's terrestrial magnetosphere - ionosphere system, resulted in geomagnetic storms. During the main phase of associated storms, along with high density plasma structures, polarity reversals in the Y-component (dawn-to-dusk) of the interplanetary electric field seem to trigger major auroral substorms with concomitant changes in the polar ionospheric electric field. Here, we examine the cases where plasma dynamics and magnetic structuring in the presence of the prompt penetration of the electric field into the equatorial ionosphere affected the space weather while highlighting the complex geomagnetic storm-substorm relationship.
On the onset of recurrent eruptions of a filament observed during August 2012
Authors: Srivastava Nandita , Joshi Anand D. , Mathew Shibu K. 
Published: January 2014

AbstractWe report observations of a long filament that underwent recurrent partial eruptions on August 4, 6, and 8, 2012. The filament reappeared in the subsequent rotation of the Sun, and disappeared completely on August 31, 2012. We implemented an automated filament detection algorithm developed by us for estimating different attributes of these filaments few hours prior to its disappearance in Hα and studied their evolution. Based on these attributes, we determine the onset time of the disappearance of Hα filaments. We then compared these onset times with that of the associated CMEs observed by LASCO/SOHO coronagraphs. This is also useful to understand temporal relationship of EUV and X-ray flux variation associated with filament disappearances in Hα. Our results show the importance of such studies in understanding the mechanism of CME initiation, particularly the role of eruptive filaments, in this process.
Stellar ejecta from falling comet-like bodies: young stars
Authors: Ibodov Firuz S. , Ibadov Subhon 
Published: January 2014

AbstractHigh-resolution spectral observations of young stars with dense protoplanetary discs like Beta Pictoris led to the discovery of variable emission lines of metal atoms, Na, Fe etc., that indicate the presence of fluxes of comet-like evaporating bodies falling onto the stars, FEBs. Assuming the presence of stellar atmospheres similar to the solar one, we show that passages of the FEBs through the stellar chromosphere and photosphere with velocities around 600 km/s will be accompanied by aerodynamic crushing of the nuclei, transverse expansion of the crushed matter, “explosion” of the flattened nuclei in a relatively very thin sub-photosphere layer due to sharp deceleration, and impulse production of a hot plasma. The impulsive rise of the layer's temperature and density lead to the generation of a strong “blast” shock wave and shock wave-induced ejection/eruption of hot plasma into space above the chromosphere. Observations of such impact-induced high-temperature phenomena are of interest for the physics/prognosis of stellar/solar flares as well as physics of comets.
The Heliophysics Feature Catalogue, a tool for the study of solar features
Authors: Bonnin Xavier , Fuller Nicolas , Renié Christian , Aboudarham Jean , Cecconi Baptiste , Bentley Robert D. , Csillaghy André 
Published: January 2014

AbstractThe behavior of filaments and prominences during the Solar Cycle is a signature of Sun's activity. It is therefore important to follow their evolution during the cycle, in order to be able to associate it with the various phases of the Solar Cycle as well as with other Solar features or events. The virtual observatory HELIO provides information that can be used for such studies, especially its Heliophysics Feature Catalogue gives a unique access to the description of various features during around one cycle. Features available are: filaments, prominences, photospheric and coronal active regions, coronal radio emission, type III radio bursts, coronal holes and sunspots. Web interfaces allow the user to query data for these features. Useful information can also be shared with other HELIO services, such as Heliophysics Event Catalogue, which provides access to dozens of tables of events such as flares, CMEs, . . .
Infrared Stokes Polarimeter at NAOJ/Mitaka
Authors: Hanaoka Yoichiro , Sakurai Takashi ,   IRMag Group
Published: January 2014

AbstractWe have been operating an infrared Stokes spectro-polarimeter, whose observing wavelength bands include the He i 10830 Å and Fe i 15648 Å lines. A couple of full-Sun, full-Stokes maps in both wavelength bands are taken on a daily basis, with the polarization sensitivity better than 10−3. With this sensitivity, the helium polarization maps clearly show the atomic and Hanlé polarizations besides the Zeeman polarization, particularly in prominences/filaments. On these polarization maps, we can track the magnetic field signals of the prominences/filaments during their passages on the solar disk. Therefore, this instrument works as a ‘synoptic prominence magnetograph’. Our preliminary study of the linear polarizations seen in quiescent filaments suggests that the magnetic field producing the polarization signals is located at the bottom part of a flux-rope, which supports a filament.
A system for near real-time detection of filament eruptions at Kanzelhöhe Observatory
Authors: Pötzi Werner , Riegler Gernot , Veronig Astrid , Pock Thomas , Möstl Ute 
Published: January 2014

AbstractKanzelhöhe Observatory (kso.ac.at) performs regular high-cadence full-disk observations of the solar chromosphere in the Hα and CaIIK spectral lines as well as the solar photosphere in white-light. In the frame of ESA's Space Situational Awareness (SSA) activities, a new system for near real-time Hα image provision through the SSA Space Weather (SWE) portal (swe.ssa.esa.int) and for automatic alerting of flares and erupting filaments is under development. Image segmentation algorithms, based on optical flow image registration, for the automatic detection of solar filaments in real time Hα images have been developed and implemented at the Kanzelhöhe observing system. We present first results of this system with respect to the automatic recognition and segmentation of filaments and filament eruptions on the Sun.
Solar Activity Monitoring of Flares and CMEs Precursors through Lyman-Alpha Imaging and Tracking of Filaments and Prominences
Authors: Damé Luc , Khaled Safinaz A. 
Published: January 2014

AbstractWe investigate the advantages of imaging solar filaments and prominences in Lyman-Alpha, coupled to H-Alpha on ground, to develop more reliable precursors indicators for large flares, several hours before their occurrence.
The Space Weather & Ultraviolet Solar Variability Microsatellite Mission (SWUSV)
Authors: Damé Luc ,   The SWUSV Team (Mustapha Meftah, Alain Hauchecorne, Philippe Keckhut, Alain Sarkissian, Marion Marchand, Abdenour Irbah, Éric Quémerais, Slimane Bekki, Thomas Foujols, Matthieu Kretzschmar, Gaël Cessateur, Alexander Shapiro, Werner Schmutz, Sergey Kuzin, Vladimir Slemzin, Sergey Bogachev, José Merayo, Peter Brauer, Kanaris Tsinganos, Antonis Paschalis, Ayman Mahrous, Safinaz A. Khaled, Ahmed Ghitas, Besheir Marzouk, Amal Zaki, Ahmed A. Hady, Rangaiah Kariyappa)
Published: January 2014

AbstractWe present a summary of the scientific objectives, payload and mission profile of the Space Weather & Ultraviolet Solar Variability Microsatellite Mission (SWUSV) proposed to CNES and ESA (small mission).