Search Publications
On the Nature and Genesis of EUV Waves: A Synthesis of Observations from SOHO, STEREO, SDO, and Hinode (Invited Review)
Vourlidas, Angelos; Patsourakos, Spiros
A major, albeit serendipitous, discovery of the SOlar and Heliospheric Observatory mission was the observation by the Extreme Ultraviolet Telescope (EIT) of large-scale extreme ultraviolet (EUV) intensity fronts propagating over a significant fraction of the Sun's surface. These so-called EIT or EUV waves are associated with eruptive phenomena and…
Computer Vision for the Solar Dynamics Observatory (SDO)
Wiegelmann, T.; Hochedez, J. F.; Raouafi, N. -E. +22 more
In Fall 2008 NASA selected a large international consortium to produce a comprehensive automated feature-recognition system for the Solar Dynamics Observatory (SDO). The SDO data that we consider are all of the Atmospheric Imaging Assembly (AIA) images plus surface magnetic-field images from the Helioseismic and Magnetic Imager (HMI). We produce r…
Relation Between Coronal Hole Areas on the Sun and the Solar Wind Parameters at 1 AU
Temmer, M.; Veronig, A. M.; Vršnak, B. +1 more
We analyze the relationship between the coronal hole (CH) characteristics on the Sun (area, position, and intensity levels) and the corresponding solar wind parameters (solar wind speed v, proton temperature T, proton density n, and magnetic field strength B) measured in situ at 1 AU with a 6-h time resolution. We developed a histogram-based inten…
Validation of the 3D AMR SIP-CESE Solar Wind Model for Four Carrington Rotations
Wu, S. T.; Feng, Xueshang; Xiang, Changqing +5 more
We carry out the adaptive mesh refinement (AMR) implementation of our solar-interplanetary space-time conservation element and solution element (CESE) magnetohydrodynamic model (SIP-CESE MHD model) using a six-component grid system (Feng, Zhou, and Wu, Astrophys. J.655, 1110, 2007; Feng et al., Astrophys. J.723, 300, 2010). By transforming the gov…
Nonlinear Force-Free Extrapolation of Emerging Flux with a Global Twist and Serpentine Fine Structures
van Driel-Gesztelyi, L.; Démoulin, P.; Baker, D. +5 more
We study the flux emergence process in NOAA active region 11024, between 29 June and 7 July 2009, by means of multi-wavelength observations and nonlinear force-free extrapolation. The main aim is to extend previous investigations by combining, as much as possible, high spatial resolution observations to test our present understanding of small-scal…
Hinode Flare Catalogue
Masuda, S.; Watanabe, K.; Segawa, T.
We describe a catalogue of solar flares observed by the three instruments (SOT, XRT, EIS) onboard the Hinode satellite. From the launch of the Hinode satellite in September 2006 until late 2011, about 5000 solar flares (larger than A-class in the GOES classification) occurred during the five-year period of Hinode observations, and more than half o…
Magnetic Topology of Active Regions and Coronal Holes: Implications for Coronal Outflows and the Solar Wind
Mandrini, C. H.; van Driel-Gesztelyi, L.; Culhane, J. L. +8 more
During 2 - 18 January 2008 a pair of low-latitude opposite-polarity coronal holes (CHs) were observed on the Sun with two active regions (ARs) and the heliospheric plasma sheet located between them. We use the Hinode/EUV Imaging Spectrometer (EIS) to locate AR-related outflows and measure their velocities. Solar-Terrestrial Relations Observatory (…
The Solar Wind Energy Flux
Issautier, K.; Meyer-Vernet, N.; Le Chat, G.
The solar-wind energy flux measured near the Ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10 %, and that this quantity varies weakly over t…
3D Reconstruction of a Rotating Erupting Prominence
Török, T.; Thompson, W. T.; Kliem, B.
A bright prominence associated with a coronal mass ejection (CME) was seen erupting from the Sun on 9 April 2008. This prominence was tracked by both the Solar Terrestrial Relations Observatory (STEREO) EUVI and COR1 telescopes, and was seen to rotate about the line of sight as it erupted; therefore, the event has been nicknamed the "Cartwheel CME…
Predictions of Energy and Helicity in Four Major Eruptive Solar Flares
Qiu, Jiong; Longcope, Dana W.; Kazachenko, Maria D. +1 more
In order to better understand the solar genesis of interplanetary magnetic clouds (MCs), we model the magnetic and topological properties of four large eruptive solar flares and relate them to observations. We use the three-dimensional Minimum Current Corona model (Longcope, 1996, Solar Phys.169, 91) and observations of pre-flare photospheric magn…