Search Publications
Large Field-of-View Spectropolarimetric Observations with a Large Aperture Telescope
Aulanier, G.; Molodij, G.
In the context of the increasing interest in large-aperture telescopes dedicated to the Sun, we present a study to evaluate the adaptive-optics system limitations on the requirements expected for magnetic-field extrapolations and data-driven MHD simulations of active regions. The questions we address include: What is the size of the field of view …
Production of High-Temperature Plasmas During the Early Phases of a C9.7 Flare. II. Bi-directional Flows Suggestive of Reconnection in a Pre-flare Brightening Region
Hara, H.; Watanabe, T.; Harra, L. K. +1 more
The 6 June 2007 16:55 UT flare was well observed with high time-cadence sparse raster scans by the EUV Imaging Spectrometer (EIS) on board the Hinode spacecraft. The observation covers an active region area of 240 arcsec × 240 arcsec with the 1 arcsec slit in about 160 seconds.
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…