432 citations · 802 across the 13 of their papers we have counts for
13 papers
Probability Distribution Functions of Solar and Stellar Flares
Takashi Sakurai
We studied the soft X-ray data of solar flares and found that the distribution functions of flare fluence are successfully modeled by tapered power law or gamma function distributi…
Probability Distribution Functions of Sunspot Magnetic Flux
Takashi Sakurai, Shin Toriumi
We have investigated the probability distributions of sunspot area and magnetic flux by using the data from Royal Greenwich Observatory and USAF/NOAA. We have constructed a sample…
Internetwork Magnetic Fields Seen in Fe I 1564.8 nm
Yoichiro Hanaoka, Takashi Sakurai
We studied the properties of internetwork magnetic fields in the solar photosphere taking advantage of full-disk Stokes maps of the \ion{Fe}{1} 1564.8 nm line, which were obt…
Synoptic solar observations of the Solar Flare Telescope focusing on space weather
Yoichiro Hanaoka, Takashi Sakurai, Ken'ichi Otsuji +2
The solar group at the National Astronomical Observatory of Japan is conducting synoptic solar observations with the Solar Flare Telescope. While it is a part of a long-term solar…
Super-strong Magnetic Field in Sunspots
Takenori J. Okamoto, Takashi Sakurai
Sunspots are the most notable structure on the solar surface with strong magnetic fields. The field is generally strongest in a dark area (umbra), but sometimes stronger fields are…
Statistical Study of the Magnetic Field Orientation in Solar Filaments
Yoichiro Hanaoka, Takashi Sakurai
We have carried out a statistical study of the average orientation of the magnetic field in solar filaments with respect to their axes for more than 400 samples, based on data take…