Search Publications
A three-dimensional velocity of an erupting prominence prior to a coronal mass ejection
Shibata, Kazunari; Ishii, Takako T.; Kitai, Reizaburo +10 more
We present a detailed three-dimensional (3D) view of a prominence eruption, coronal loop expansion, and coronal mass ejections (CMEs) associated with an M4.4 flare that occurred on 2011 March 8 in the active region NOAA 11165. Full-disk Hα images of the flare and filament ejection were successfully obtained by the Flare Monitoring Telescope (FMT) …
Coronal behavior before the large flare onset
Kusano, Kanya; Bamba, Yumi; Imada, Shinsuke
Flares are a major explosive event in our solar system. They are often followed by a coronal mass ejection that has the potential to trigger geomagnetic storms. There are various studies aiming to predict when and where the flares are likely to occur. Most of these studies mainly discuss the photospheric and chromospheric activity before the flare…
Possible signature of Alfvén wave dissipation in the localized magnetic funnels of the equatorial solar corona
Dwivedi, Bhola N.; Mohan, Anita; Srivastava, Abhishek Kumar
We analyse the Hinode/EIS 2″-spectroscopic scan data containing the spectral line formed at typical inner coronal temperature. The strong Fe XII 195.120 Å line shows the existence of funnel-like expanding flux-tubes which exhibit the signature of blue-/red-shifted plasma motions in the off-limb equatorial corona. These coronal funnels expand in th…
Energetic Relations between the Disappearing Solar Filaments and the Associated Flare Arcades
Shibata, Kazunari; Morimoto, Taro; Kurokawa, Hiroki +1 more
We present the temporal and statistical relations between the mechanical energies of disappearing solar filaments and the thermal energies of the associated flare arcades in soft X-rays. Measuring the 3-D velocity fields of 10 eruptive filaments, we calculated their mechanical energy gain rate, ɛmc, per unit volume and compared it to th…
Spectroscopic Studies of Limb Spicules. I Radial and Turbulent Velocities
Shoji, Makiko; Nishikawa, Takara; Kitai, Reizaburo +1 more
We made high-resolution spectroscopic observations of limb spicules in Hα using the Vertical Spectrograph of Domeless Solar Telescope at Hida Observatory. While more than half of the observed spicules have Gaussian line-profiles, some spicules have distinctly asymmetric profiles, which can be fitted to two Gaussian components. The faster component…
On the Relation between Surge Activities and a Photospheric Horizontal Velocity Field
Kitai, Reizaburo
A photospheric horizontal velocity field was observed in an active region, NOAA 8375, which showed high Hα surge activities on 1998 November 6. From analyses of Hα images, the photospheric horizontal velocity field, and the magnetic field in and around the active region, we found the following: (1) Meso-granular or supergranular photospheric horiz…
Coronal Dimming Observed with Hinode: Outflows Related to a Coronal Mass Ejection
Harra, Louise K.; Hara, Hirohisa; Young, Peter R. +5 more
Coronal dimming has been a signature used to determine the source of plasma that forms part of a coronal mass ejection (CME) for many years. Generally dimming is detected through imaging instruments such as SOHO EIT by taking difference images. Hinode tracked active region 10930 from which there were a series of flares. We combined dimming observa…
Hinode SP Vector Magnetogram of AR10930 and Its Cross-Comparison with MDI
Moon, Yong-Jae; Shimojo, Masumi; Tsuneta, Saku +17 more
We present one Hinode Spectropolarimeter (SP) magnetogram of AR 10930 that produced several major flares. The inversion from Stokes profiles to magnetic field vectors was made using the standard Milne-Eddington code. We successfully applied the Uniform Shear Method for resolving the 180° ambiguity to the magnetogram. The inversion gave very strong…
Hinode Observations of the Onset Stage of a Solar Filament Eruption
Narukage, Noriyuki; Kano, Ryohei; Sakao, Taro +12 more
We used Hinode X-Ray Telescope (XRT) and Solar Optical Telescope (SOT) filtergraph (FG) Stokes-V magnetogram observations, to study the early onset of a solar eruption that includes an erupting filament that we observe in TRACE EUV images. The filament undergoes a slow rise for at least 20min prior to its fast eruption and strong soft X-ray (SXR) …
Diagnostics of Radio Fine Structures around 3 GHz with Hinode Data in the Impulsive Phase of an X3.4/4B Flare Event on 2006 December 13
Chen, Bin; Sakurai, Takashi; Yan, Yihua +1 more
On 2006 December 13 during the solar minimum, the superactive region NOAA 10930 at the S05W33 disk location produced an X3.4/4B flare at 02:40UT. Fine structures were observed in the radio spectra, which included spikes, reverse slope-type III bursts, type-U burst, V-shaped burst, pulsations, zebra patterns, and firstly discovered sub-second spiky…