output
20072025
most citedLong-Lasting Extreme Magnetic Storm Activities in 1770 Found in Historical Documents

61 citations

11 papers

cs.CV2025★ 2 cited

BEVANet: Bilateral Efficient Visual Attention Network for Real-Time Semantic Segmentation

Ping-Mao Huang, I-Tien Chao, Ping-Chia Huang +2

Real-time semantic segmentation presents the dual challenge of designing efficient architectures that capture large receptive fields for semantic understanding while also refining…

cs.LG2024★ 2 cited

Aligning Few-Step Diffusion Models with Dense Reward Difference Learning

Ziyi Zhang, Li Shen, Sen Zhang +6

Few-step diffusion models enable efficient high-resolution image synthesis but struggle to align with specific downstream objectives due to limitations of existing reinforcement le…

astro-ph.SR2018★ 32 cited

A Great Space Weather Event in February 1730

Hisashi Hayakawa, Yusuke Ebihara, José M. Vaquero +9

Aims. Historical records provide evidence of extreme magnetic storms with equatorward auroral extensions before the epoch of systematic magnetic observations. One significant magne…

physics.hist-ph2018★ 13 cited

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…

astro-ph.SR2017★ 22 cited

Iwahashi Zenbei's Sunspot Drawings in 1793 in Japan

Hisashi Hayakawa, Kiyomi Iwahashi, Harufumi Tamazawa +2

Three Japanese sunspot drawings associated with Iwahashi Zenbei (1756-1811) are shown here from contemporary manuscripts and woodprint documents with the relevant texts. We reveale…

astro-ph.SR2017★ 61 cited

Long-Lasting Extreme Magnetic Storm Activities in 1770 Found in Historical Documents

Hisashi Hayakawa, Kiyomi Iwahashi, Yusuke Ebihara +8

Dim red aurora at low magnetic latitudes is a visual and recognized manifestation of geomagnetic storms. The great low-latitude auroral displays seen throughout East Asia on 16-18…

astro-ph.SR2017★ 16 cited

Records of Auroral Candidates and Sunspots in Rikkokushi, Chronicles of Ancient Japan from Early 7th Century to 887

Hisashi Hayakawa, Kiyomi Iwahashi, Harufumi Tamazawa +5

In this article, we present the results of the surveys on sunspots and auroral candidates in Rikkokushi, Japanese Official Histories from the early 7th century to 887 to review the…

astro-ph.SR2016★ 32 cited

Historical Auroras in the 990s: Evidence for Great Magnetic Storms

Hisashi Hayakawa, Harufumi Tamazawa, Yurina Uchiyama +5

Recently, a significant carbon-14 enhancement in the year 994 in tree rings has been found, suggesting an extremely large cosmic ray flux event during a short period. The origin of…

physics.hist-ph2016★ 33 cited

The earliest drawings of datable auroras and a two-tail comet from the Syriac Chronicle of Zūqnīn

Hisashi Hayakawa, Yasuyuki Mitsuma, Yasunori Fujiwara +7

People have probably been watching the sky since the beginning of human history. Observers in pre-telescopic ages recorded anomalous events and these astronomical records in the hi…

astro-ph.SR2016★ 40 cited

East Asian Observations of Low Latitude Aurora during the Carrington Magnetic Storm

Hisashi Hayakawa, Kiyomi Iwahashi, Harufumi Tamazawa +6

The magnetic storm around 1859 September 2, caused by so-called Carrington flare, was the most intense in the history of modern scientific observations, and hence is considered to…

physics.med-ph2007★ 15 cited

Computational modeling of beam-customization devices for heavy-charged-particle radiotherapy

Nobuyuki Kanematsu, Shunsuke Yonai, Azusa Ishizaki +1

A model for beam customization with collimators and a range-compensating filter based on the phase-space theory for beam transport is presented for dose distribution calculation in…