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Post-Eruption Arcades and Interplanetary Coronal Mass Ejections
Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +1 more
We compare the temporal and spatial properties of posteruption arcades (PEAs) associated with coronal mass ejections (CMEs) at the Sun that end up as magnetic cloud (MC) and non-MC events in the solar wind. We investigate the length, width, area, tilt angle, and formation time of the PEAs associated with 22 MC and 29 non-MC events and we find no d…
Signatures of Slow Solar Wind Streams from Active Regions in the Inner Corona
Berghmans, D.; Slemzin, V.; Harra, L. +3 more
The identification of solar-wind sources is an important question in solar physics. The existing solar-wind models (e.g., the Wang-Sheeley-Arge model) provide the approximate locations of the solar wind sources based on magnetic field extrapolations. It has been suggested recently that plasma outflows observed at the edges of active regions may be…
The 3D Geometry of Active Region Upflows Deduced from Their Limb-to-Limb Evolution
Mandrini, C. H.; van Driel-Gesztelyi, L.; Démoulin, P. +1 more
We analyze the evolution of coronal plasma upflows from the edges of AR 10978, which has the best limb-to-limb data coverage with Hinode's EUV Imaging Spectrometer (EIS). We find that the observed evolution is largely due to the solar rotation progressively changing the viewpoint of nearly stationary flows. From the systematic changes in the upflo…
Multiscale Magnetic Underdense Regions on the Solar Surface: Granular and Mesogranular Scales
Giordano, S.; Berrilli, F.; Scardigli, S.
The Sun is a non-equilibrium, dissipative system subject to an energy flow that originates in its core. Convective overshooting motions create temperature and velocity structures that show a temporal and spatial multiscale evolution. As a result, photospheric structures are generally considered to be a direct manifestation of convective plasma mot…
The Dynamics of the Solar Radiative Zone
Eff-Darwich, A.; Korzennik, S. G.
The dynamics of the solar radiative interior are still poorly constrained by comparison to the convective zone. This disparity is even more marked when we attempt to derive meaningful temporal variations. Many data sets contain a small number of modes that are sensitive to the inner layers of the Sun, but we found that the estimates of their uncer…
Fast Magnetoacoustic Waves in a Fan Structure Above a Coronal Magnetic Null Point
Karlický, M.; Mészárosová, H.; Dudík, J. +2 more
We analyze the 26 November 2005 solar radio event observed interferometrically at frequencies of 244 and 611 MHz by the Giant Metrewave Radio Telescope (GMRT) in Pune, India. These observations are used to make interferometric maps of the event at both frequencies with the time cadence of 1 s from 06:50 to 07:12 UT. These maps reveal several radio…
ARTEMIS II: A Second-Generation Catalog of LASCO Coronal Mass Ejections Including Mass and Kinetic Energy
Llebaria, A.; Lamy, P.; Floyd, O. +1 more
The ARTEMIS-I catalog of coronal mass ejections (CMEs) was initially developed on a first generation of low-resolution synoptic maps constructed from the SOHO/LASCO-C2 images of the K-corona and resulted in an online database listing all events detected since January 1996 (Boursier et al., Solar Phys.257, 125, 2009). A new generation of synoptic m…
Study of a Prominence Eruption using PROBA2/SWAP and STEREO/EUVI Data
Mierla, M.; Zhukov, A. N.; Berghmans, D. +6 more
Observations of the early rise and propagation phases of solar eruptive prominences can provide clues about the forces acting on them through the behavior of their acceleration with height. We have analyzed such an event, observed on 13 April 2010 by SWAP on PROBA2 and EUVI on STEREO. A feature at the top of the erupting prominence was identified …
A Comparison of Solar Cycle Variations in the Equatorial Rotation Rates of the Sun's Subsurface, Surface, Corona, and Sunspot Groups
Javaraiah, J.
Using the Solar Optical Observing Network (SOON) sunspot-group data for the period 1985 - 2010, the variations in the annual mean equatorial-rotation rates of the sunspot groups are determined and compared with the known variations in the solar equatorial-rotation rates determined from the following data: i) the plasma rotation rates at 0.94R…
Sun-as-a-Star Observation of Flares in Lyman α by the PROBA2/LYRA Radiometer
Kretzschmar, M.; Dammasch, I. E.; Dominique, M.
There are very few reports of flare signatures in the solar irradiance at H I Lyman α at 121.5 nm, i.e. the strongest line of the solar spectrum. The LYRA radiometer onboard PROBA2 has observed several flares for which unambiguous signatures have been found in its Lyman-α channel. Here we present a brief overview of these observations followed by …