Search Publications
Observation of Plasma Instabilities in Quiescent Prominences
Title, A.; Berger, T.; Frank, Z. +2 more
We study dynamics of quiescent prominences using several data sets taken with the Solar Optical Telescope (SOT) on Hinode. We find a number of processes occurring at different stages of prominence evolution that are common for all of our chosen cases and, having universal character, can be related to fundamental plasma instabilities. We combine th…
Modeling of EIS Spectrum Drift from Instrumental Temperatures
Fredvik, T.; Hara, H.; Watanabe, T. +2 more
An empirical model has been developed to reproduce the drift of the spectrum recorded by the EIS on Hinode using instrumental temperatures and relative motion of the spacecraft. The EIS spectrum shows an artificial drift in wavelength dimension in sync with the revolution of the spacecraft, which is caused by temperature variations inside the spec…
Outflows at the Edges of an Active Region in a Coronal Hole: A Signature of Active Region Expansion?
van Driel-Gesztelyi, L.; Baker, D.; Murray, M. J. +1 more
Outflows of plasma at the edges of active regions surrounded by quiet Sun are now a common observation with the Hinode satellite. While there is observational evidence to suggest that the outflows are originating in the magnetic field surrounding the active regions, there is no conclusive evidence that reveals how they are driven. Motivated by obs…
The Diagnostics of the κ-Distributions from EUV Spectra
Dzifčáková, E.; Kulinová, A.
The EUV lines suitable to diagnose possible κ-distributions in the solar corona are examined. A set of synthetic spectra for various values of the κ-parameter, characterizing the non-thermal κ-distributions, electron densities, and the mean energy of the distributions are calculated in the spectral range corresponding to the Hinode/EIS and Coronas…
Multiwavelength Study of the M8.9/3B Solar Flare from AR NOAA 10960
Srivastava, A. K.; Filippov, B.; Kumar, Pankaj +1 more
We present a multiwavelength analysis of a long-duration, white-light solar flare (M8.9/3B) event that occurred on 04 June 2007 from AR NOAA 10960. The flare was observed by several spaceborne instruments, namely SOHO/MDI, Hinode/SOT, TRACE, and STEREO/SECCHI. The flare was initiated near a small, positive-polarity, satellite sunspot at the center…
Solar Intranetwork Magnetic Elements: Evolution and Lifetime
Wang, J. X.; Zhou, G. P.; Jin, C. L.
Based on Hinode SOT/NFI observations with greatly improved spatial and temporal resolution and polarization sensitivity, the lifestory of the intranetwork (IN) magnetic elements are explored in a solar quiet region. A total of 2282 IN elements are followed from their appearance to disappearance and their fluxes measured. By tracing individual IN e…
Response of the Solar Atmosphere to the Emergence of `Serpentine' Magnetic Field
Tsuneta, S.; Hara, H.; Harra, L. K. +3 more
Active region magnetic flux that emerges to the photosphere from below will show complexity in the structure, with many small-scale fragmented features appearing in between the main bipole and then disappearing. Some fragments seen will be absorbed into the main polarities and others seem to cancel with opposite magnetic field. In this paper we in…
Revealing the Fine Structure of Coronal Dimmings and Associated Flows with Hinode/EIS. Implications for Understanding the Source Regions of Sustained Outflow Following CMEs
van Driel-Gesztelyi, L.; Harra, L. K.; Wills-Davey, M. J. +1 more
We study two CME events on 13 and 14 December 2006 that were associated with large-scale dimmings. We study the eruptions from pre-event on 11 December through the recovery on 15 December, using a combination of Hinode/EIS, SOHO/EIT, SOHO/MDI, and MLSO Hα data. The GOES X-class flares obscured the core dimmings, but secondary dimmings developed re…
The Impact of New EUV Diagnostics on CME-Related Kinematics
De Pontieu, Bart; McIntosh, Scott W.; Leamon, Robert J.
We present the application of novel diagnostics to the spectroscopic observation of a Coronal Mass Ejection (CME) on disk by the Extreme Ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. We apply a recently developed line profile asymmetry analysis to the spectroscopic observation of NOAA AR 10930 on 14 - 15 December 2006 to three r…
Pre-Flare Flows in the Corona
van Driel-Gesztelyi, L.; Green, L. M.; Harra, L. K. +2 more
Solar flares take place in regions of strong magnetic fields and are generally accepted to be the result of a resistive instability leading to magnetic reconnection. When new flux emerges into a pre-existing active region it can act as a flare and coronal mass ejection trigger. In this study we observed active region 10955 after the emergence of s…