Search Publications
Statistical Studies on the Excess Peak Flux in Soft X-rays and EUV Bands from Solar Flares
Cai, L.; Zhang, D. H.; Hao, Y. Q. +2 more
Based on the solar X-ray data in the band of 0.1 - 0.8 nm observed by Geostationary Operational Environmental Satellites (GOES), the XUV and EUV data in the bands of 26 - 34 nm and 0.1 - 50 nm observed by the Solar EUV Monitor (SEM) onboard the Solar and Heliospheric Observatory (SOHO), a statistical analysis on the excess peak flux (the pre-flare…
Study of the Three-Dimensional Shape and Dynamics of Coronal Loops Observed by Hinode/EIS
Gontikakis, C.; Tsinganos, K.; Georgoulis, M. K. +2 more
We study plasma flows along selected coronal loops in NOAA Active Region 10926, observed on 3 December 2006 with Hinode'sEUVImaging Spectrograph (EIS). From the shape of the loops traced on intensity images and the Doppler shifts measured along their length we compute their three-dimensional (3D) shape and plasma flow velocity using a simple geome…
Reversed Drifting Quasi-periodic Pulsating Structure in the X1.3 Solar Flare on 30 July 2005
Wang, Rui; Tan, Baolin; Tan, Chengming +1 more
Based on the analysis of the microwave observations at the frequency range of 2.60 - 3.80 GHz in the solar X1.3 flare event observed at the Solar Broadband RadioSpectrometer in Huairou (SBRS/Huairou) on 30 July 2005, an interesting reversed drifting quasi-periodic pulsating structure (R-DPS) is confirmed. The R-DPS is mainly composed of two drifti…
A Survey of the Hard X-Ray Characteristics of Seismically Active and Quiet White-Light Flares
Matthews, S. A.; Pedram, E.
Various mechanisms have been proposed to explain how seismic waves can be generated during a solar flare, several of which include a major role for accelerated electrons. To address this question further, we have selected two samples of white-light flares (WLFs): one that has associated sunquakes, and one that does not. We focus particularly on th…
Ca II Transient Brightenings Associated with Canceling Magnetic Features
Chae, Jongchul; Park, Soyoung
We analyzed transient Ca II H brightening associated with small-scale canceling magnetic features (CMFs) in the quiet Sun near disk center using Ca II H filter images and Na D1 magnetograms of Hinode/SOT. We found that in most Ca II brightening events related to CMFs the Ca II H intensity peaks after the magnetic flux cancellation. More…
Studying Sun-Planet Connections Using the Heliophysics Integrated Observatory (HELIO)
Bocchialini, K.; Lavraud, B.; Bonnin, X. +18 more
The Heliophysics Integrated Observatory (HELIO) is a software infrastructure involving a collection of web services, heliospheric data sources (e.g., solar, planetary, etc.), and event catalogues - all of which are accessible through a unified front end. In this paper we use the HELIO infrastructure to perform three case studies based on solar eve…
Energetic Particles Measured in and out of the Ecliptic Plane During the Last Gnevyshev Gap
Rodríguez-Pacheco, J.; Gómez-Herrero, R.; Heber, B. +1 more
We analyzed the temporal variation of energetic particles measured by the Low Energy Telescope (LET), the Kiel Electron Telescope (KET), and the High Energy Telescope (HET) instruments aboard Ulysses and the Electron Proton Helium Instrument (EPHIN) aboard SOHO during the last solar magnetic field polarity reversal in 2001. We have found two perio…
Unusual Emissions at Various Energies Prior to the Impulsive Phase of the Large Solar Flare and Coronal Mass Ejection of 4 November 2003
Su, Yang; Holman, Gordon D.; Kaufmann, Pierre +6 more
The GOES X28 flare of 4 November 2003 was the largest ever recorded in its class. It produced the first evidence for two spectrally separated emission components, one at microwaves and the other in the THz range of frequencies. We analyzed the pre-flare phase of this large flare, twenty minutes before the onset of the major impulsive burst. This p…
Numerical Simulation of a Solar Active Region. I: Bastille Day Flare
Charbonneau, Paul; Vincent, Alain; Dubé, Caroline
We present three-dimensional unsteady modeling and numerical simulations of a coronal active region, carried out within the compressible single-fluid MHD approximation. We focus on AR 9077 on 14 July 2000, and the triggering of the X5.7 GOES X-ray class "Bastille Day" flare. We simulate only the lower corona, although we include a virtual photosph…
Outflow Velocity Structure in the Upper Transition Region and Corona
Abbo, Lucia; Gabriel, Alan
Outflow velocity maps in the quiet Sun and coronal hole regions have been observed with the EUV Imaging Spectrometer on Hinode over a range of coronal and transition region temperatures, in order to correlate the solar wind with effects due to the underlying supergranule network and to coronal holes. The cell structure has been identified using da…