activity
20182021
most citedRevisiting Kunitomo's Sunspot Drawings during 1835-1836 in Japan

14 citations · 32 across the 5 of their papers we have counts for

collaborators

6 papers

astro-ph.SR20211 cited

Energy conversion rate of an active region transient brightening estimated by a spectroscopic observation of Hinode

Toshiki Kawai, Shinsuke Imada

We statistically estimate the conversion rate of the energy released during an active-region transient brightening to Doppler motion and thermal and non-thermal energies. We used t…

astro-ph.SR20205 cited

Energy distribution of small-scale flares derived using genetic algorithm

Toshiki Kawai, Shinsuke Imada

To understand the mechanism of coronal heating, it is crucial to derive the contribution of small-scale flares, the so-called nanoflares, to the heating up of the solar corona. To…

astro-ph.SR202011 cited

Nowcast of an EUV dynamic spectrum during solar flares

Toshiki Kawai, Shinsuke Imada, Shohei Nishimoto +2

In addition to X-rays, extreme ultraviolet (EUV) rays radiated from solar flares can cause serious problems, such as communication failures and satellite drag. Therefore, methods f…

astro-ph.SR20191 cited

Velocity Structure and Temperature Dependence of Extreme-Ultraviolet Jet Observed by Hinode

Toshiki Kawai, Natsuo Kanda, Shinsuke Imada

The acceleration mechanism of EUV/X-ray jets is still unclear. For the most part, there are two candidates for the mechanism. One is magnetic reconnection, and the other is chromos…

astro-ph.SR201914 cited

Revisiting Kunitomo's Sunspot Drawings during 1835-1836 in Japan

Masashi Fujiyama, Hisashi Hayakawa, Tomoya Iju +7

We revisit the sunspot drawings made by the Japanese astronomer Kunitomo Toubei during 1835-1836 and recount the sunspot group number for each image. There are two series of drawin…

physics.hist-ph2018

Sunspot Drawings by Japanese Official Astronomers in 1749-1750

Hisashi Hayakawa, Kiyomi Iwahashi, Masashi Fujiyama +7

Sunspot observations with telescopes in 18th century were carried out in Japan as well. One of these sunspot observations is recorded in an account called Sansaizusetsu narabini Ka…