Researcher basic information

• 博士 (理学), 東京大学, Mar. 2020

• https://researchmap.jp/yuuki_wada?lang=en

• https://orcid.org/0000-0001-8953-3345
• https://jglobal.jst.go.jp/detail?JGLOBAL_ID=202101001748055398
• https://yuuki-wd.space
• https://en.yuuki-wd.space

• https://orcid.org/0000-0001-8953-3345

• 202101001748055398

• Energy Engineering, Nuclear engineering, radiation measurement
• Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering), Control and system engineering, meteorological sensing system
• Natural Science, Experimental studies related to particle-, nuclear-, cosmic ray and astro-physics, high-energy atmospheric physics

Research activity information

• Oct. 2023, American Geophysical Union (AGU), 2022 Editor’s Citation for Excellence in Refereeing
• Feb. 2023, 井上科学振興財団, 井上研究奨励賞
• Dec. 2022, American Geophysical Union (AGU), Atmospheric and Space Electricity Early Career Award
• Mar. 2021, RIKEN, RIKEN Research Incentive Award
  Development of an observation and analysis framework to explore high-energy phenomena in lightning discharges
• Mar. 2021, Physical Society of Japan, Young Scientist Award of the Physical Society of Japan
  Observational Studies of Photonuclear Reactions Triggered by Lightning Discharges
• Mar. 2020, Graduate School of Science, The University of Tokyo, Research Encourage Award
• Jul. 2019, Japan Geoscience Union, Outstanding Student Presentation Award
  冬季雷における高エネルギー現象の観測プロジェクトの進展
• Mar. 2019, 一般社団法人 日本物理学会, 第74回年次大会 学生優秀発表賞
  雷活動に由来するガンマ線の観測プロジェクト：多地点観測の進展と大気電場・電波との協同観測
• Jul. 2017, 日本地球惑星科学連合, 学生優秀発表賞
  雷雲ガンマ線の多地点観測プロジェクト: 可搬型検出器の開発と2016年度冬季の観測成果

• Improving GSMaP Precipitation Estimates Using a Modified Kalman Filter with Lightning Flash Rate
  Archie Veloria; Hitoshi Hirose; Yuuki Wada; Syugo Hayashi; Daichi Kitahara; Tomoo Ushio
  IEEE Transactions on Geoscience and Remote Sensing, 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Rapid Recharge and Descent of Thundercloud Core Producing Gamma‐Ray Glow
  Y. Wada; T. Wu; M. Kamogawa; D. Wang; G. Okada; H. Nanto; T. Sawano; M. Kubo; D. Yonetoku; G. S. Diniz; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, 28 Dec. 2025, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
  Scientific journal
• Simulated Characteristics of On‐Ground Gamma‐Ray Glows
  G. S. Diniz; Y. Wada; Y. Ohira; K. Nakazawa; M. Tsurumi; I. T. Cruz; T. Enoto
  Journal of Geophysical Research: Atmospheres, 16 Nov. 2025, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Typical Winter TGF Lightning: Vertical Negative Leader Progression Features and Charge Structures
  Qingliu Yang; Daohong Wang; Ting Wu; David M. Smith; Yuuki Wada; Kazuhiro Nakazawa; Masashi Kamogawa
  Geophysical Research Letters, 16 Sep. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• Introduction of Lightning into the GSMaP Rainfall Measurements through Optimized Power-Law Model
  Archie Veloria; Yuuki Wada; Hitoshi Hirose; Daichi Kitahara; Syugo Hayashi; Tomoo Ushio
  Journal of Atmospheric and Oceanic Technology, 42, 6, 637, 656, American Meteorological Society, Jun. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  Lightning and rainfall are associated with severe weather conditions. These two parameters, occurring either simultaneously or with a lag, have an intrinsic relationship. This study focuses on characterizing this inherent lightning–rainfall relation, which in turn is used to perform corrections of rainfall rate estimation based on satellite measurements. The approach is to analyze the lightning–rainfall relation at varying spatial and temporal scales and to select the best resolution at which the lightning flash rate can best model rainfall volume. Then, the parameters of a power-law model are optimized to assimilate lightning flashes into the Global Satellite Mapping of Precipitation (GSMaP) rainfall product. The results revealed that the lightning and rainfall relationship varies depending on the weather system. The lightning–rainfall relation, which can be empirically described by a power law, is most apparent in thunderstorms followed by frontal systems and least in typhoons. The differences in relationships are due to the variations in lightning and rainfall collocation per weather system. Rainfall volumes are also found to vary heavily on low lightning flash rates. Considering the best-case resolution of 100 km and 60 min for thunderstorms, the lightning-corrected GSMaP rainfall volume shows a reduction in root-mean-square error (RMSE) by about 59% and an increase in the correlation from 0.6 to 0.7 concerning radar rainfall volume. The correction scheme is also effective from resolutions of 40 to 250 km in thunderstorms, achieving moderate positive correlations with RMSE about 5 mm h⁻¹ and below.
  
  Significance Statement
  
  Accurate and timely information on precipitation is necessary to mitigate the impacts of rainfall-related hazards. While satellites provide consistent rainfall information at wide coverage, satellite-based measurements are still prone to error. Considering the association between rainfall and lightning occurrences, we came up with a technique to improve the performance of the GSMaP rainfall measurements through the introduction of lightning data. This study is a step forward to leveraging the future global coverage of lightning measurements from satellite-based lightning mappers that can enable more accurate global rainfall estimates.
• Evolution of the Inner Accretion Flow and the White Dwarf Spin Pulse during the 2023 Outburst in GK Persei
  Mariko Kimura; Takayuki Hayashi; Yuuki Wada; Wataru Iwakiri; Shigeyuki Sako; Martina Veresvarska; Simone Scaringi; Noel Castro-Segura; Christian Knigge; Keith C. Gendreau; Zaven Arzoumanian
  The Astrophysical Journal, 985, 2, 240, 240, American Astronomical Society, 29 May 2025, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal, Abstract
  
  We present our X-ray and optical observations performed by NICER, NuSTAR, and Tomo-e Gozen during the 2023 outburst in the intermediate polar GK Persei. The X-ray spectrum consisted of three components: blackbody (BB) emission of several tens of eVs from the irradiated white dwarf (WD) surface, a source possibly including several emission lines around 1 keV, and multitemperature bremsstrahlung emission from the accretion column. The 351.3 s WD spin pulse was detected in X-rays, and the observable X-ray flux from the column drastically decreased at the off-pulse phase, which suggests that the absorption of the column by the accreting gas, called the curtain, was the major cause of the pulse. As the system became brighter in the optical, the column became fainter, the pulse amplitude became higher, and the energy dependence of pulses became weaker at <8 keV. These phenomena could be explained by the column’s more pronounced absorption by the denser curtain as mass-accretion rates increased. The BB and line fluxes rapidly decreased at the optical decline, which suggests the expansion of the innermost disk edge with decreasing accretion rates. The electron scattering or the column geometry may be associated with the almost no energy dependence of high-energy pulses. The irradiated vertically thick structure at the disk may generate optical quasi-periodic oscillations with a period of ∼5700 s.
• Downward terrestrial gamma-ray flash associated with collision of lightning leaders
  Yuuki Wada; Takeshi Morimoto; Ting Wu; Daohong Wang; Hiroshi Kikuchi; Yoshitaka Nakamura; Eiichi Yoshikawa; Tomoo Ushio; Harufumi Tsuchiya
  Science Advances, 11, 21, American Association for the Advancement of Science (AAAS), 23 May 2025, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
  Scientific journal, Lightning discharges can produce transient gamma-ray emissions called terrestrial gamma-ray flashes (TGFs), which originates from electrons accelerated to relativistic energies in strong electric fields. However, it is not yet understood how lightning produces an enormous number of relativistic electrons in dense atmospheres. We present that, thanks to a ground-based observation with optical, radio frequency and high-energy measurements focused on television transmission towers in Kanazawa, Japan, a TGF and a cloud-to-ground discharge of −56 kA occurred when a downward negative leader was colliding with an upward positive leader from the tower. Because the cloud-to-ground current followed the TGF by 30 μs, the TGF started when two leaders approached each other. Our results indicate that an immense number of electrons were produced and accelerated to relativistic energies in a strong and compact electric-field region between the two leaders.
• Angular Profile Estimation on Phased Array Weather Radar by Maximizing Marginal Likelihood
  Eiichi Yoshikawa; V. Chandrasekar; Koji Nishimura; Daichi Kitahara; Yuuki Wada; Tomoo Ushio
  2025 IEEE International Radar Conference (RADAR), 1, 6, IEEE, 03 May 2025
  International conference proceedings
• Energetic Compact Strokes as the Major Source of Downward Terrestrial Gamma‐Ray Flashes in Winter Thunderstorms
  Ting Wu; David M. Smith; Yuuki Wada; Kazuhiro Nakazawa; Manari Oguchi; Masashi Kamogawa; Tomoyuki Suzuki; Qingliu Yang; Daohong Wang
  Geophysical Research Letters, 28 Mar. 2025, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• An Upward Multi‐Pulse TGF Involved With Two Thunderstorm Cells
  K. Nakazawa; M. Oguchi; T. Wu; Y. Wada; K. Okuma; D. Wang; Y. Tsuji; Y. Omiya; M. Ando; T. Enoto; M. Tsurumi; J. Kataoka; T. Kanda; R. Iwashita; N. Koshikawa; T. Shinoda; G. Diniz; Y. Ikkatai
  Journal of Geophysical Research: Atmospheres, 28 Mar. 2025, [Peer-reviewed]
  Scientific journal
• Phase and Amplitude Correction for Adaptive Beamforming of Phased Array Weather Radar
  Yuuki Wada; Hiroshi Kikuchi; Eiichi Yoshikawa; Daichi Kitahara; Tomoo Ushio
  IEEE Transactions on Geoscience and Remote Sensing, Institute of Electrical and Electronics Engineers (IEEE), Oct. 2024, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Observation of Electrical Alignment Signatures in an Isolated Thunderstorm by Dual‐Polarized Phased Array Weather Radar and the Relationship With Intracloud Lightning Flash Rate
  Shuo Wang; Yuuki Wada; Syugo Hayashi; Tomoo Ushio; V. Chandrasekar
  Journal of Geophysical Research: Atmospheres, 129, 19, e2023JD040681, Oct. 2024, [Peer-reviewed]
  English, Scientific journal
• Investigating the electron acceleration location in winter thunderclouds by on-ground gamma-ray and radio observations
  Kazuhiro Nakazawa; Manari Oguchi; Ting Wu; Yuuki Wada; Keigo Okuma; Mii Ando; Atsuya Tanaka; Teruaki Enoto; Daohong Wang; Gabriel Diniz; Taro Shinoda; Yuko Ikkatai
  Proceedings of Science, 444, 27 Sep. 2024
  International conference proceedings
• X-Raying Neutral Density Disturbances in the Mesosphere and Lower Thermosphere induced by the 2022 Hunga-Tonga Volcano Eruption
  Satoru Katsuda; Hiroyuki Shinagawa; Hitoshi Fujiwara; Hidekatsu Jin; Yasunobu Miyoshi; Yoshizumi Miyoshi; Yuko Motizuki; Motoki Nakajima; Kazuhiro Nakazawa; Kumiko K Nobukawa; Yuichi Otsuka; Atsuki Shinbori; Takuya Sori; Chihiro Tao; Makoto S Tashiro; Yuuki Wada; Takaya Yamawaki
  Geophysical Research Letters, 29 Aug. 2024, [Peer-reviewed]
  Scientific journal
• On-ground calibration of the X-ray, gamma-ray, and relativistic electron detector onboard TARANIS
  Yuuki Wada; Philippe Laurent; Damien Pailot; Ion Cojocari; Eric Bréelle; Stéphane Colonges; Jean-Pierre Baronick; François Lebrun; Pierre-Louis Blelly; David Sarria; Kazuhiro Nakazawa; Miles Lindsey-Clark
  Journal of Astronomical Telescopes, Instruments, and Systems, 10, 02, SPIE-Intl Soc Optical Eng, 07 May 2024, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Electrical Alignment Signatures of Ice Particles Before Intracloud Lightning Activity Detected by Dual‐Polarized Phased Array Weather Radar
  Shuo Wang; Yuuki Wada; Syugo Hayashi; Tomoo Ushio; V. Chandrasekar
  Journal of Geophysical Research: Atmospheres, 16 Apr. 2024, [Peer-reviewed]
  Scientific journal
• Mitigation of Ground-Clutter Effects by Digital Beamforming With Precomputed Weighting Matrix for Phased Array Weather Radar
  Yuuki Wada; Yutaka Takata; Hiroshi Kikuchi; Daichi Kitahara; Eiichi Yoshikawa; Shigeharu Shimamura; Tomoo Ushio
  IEEE Transactions on Geoscience and Remote Sensing, 62, 1, 14, Institute of Electrical and Electronics Engineers (IEEE), Feb. 2024, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Negative Excursion of Surface Electric Fields During Gamma‐Ray Glows in Winter Thunderstorms
  Y. Wada; M. Kamogawa; M. Kubo; T. Enoto; S. Hayashi; T. Sawano; D. Yonetoku; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, 128, 21, American Geophysical Union (AGU), 07 Nov. 2023, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal, Abstract
  
  During the 2020–2021 winter season, we detected 6 gamma‐ray glows at Kanazawa University, Japan. Negative surface electric fields (E‐fields; in the sign convention of atmospheric electricity) were observed by a field mill during all the glow cases. In five of the six cases, the peak E‐field reached around −12 kV m⁻¹, and the E‐field during the glow detection was the strongest in the interval including 3 hr before and after the detection time. Therefore, negative charges should have been dominant in the thunderclouds that produced the gamma‐ray glows, and electrons were probably accelerated and multiplied by the E‐fields between a predominantly negative charge layer and a localized positive charge layer below. In addition, we extracted 8 non‐detection cases in the 2020–2021 winter season, in which surface E‐fields were stronger than −12 kV m⁻¹. In 5 of the 8 cases, radar echoes were inadequately developed, suggesting insufficient charge accumulation. On the other hand, the remaining 3 cases had well‐developed radar echoes, and there was no significant difference from the detection cases.
• Relativistic Runaway Electron Avalanche Development Near the Electric Field Threshold in Inhomogeneous Air
  G. S. Diniz; Y. Wada; Y. Ohira; K. Nakazawa; M. Tsurumi; T. Enoto
  Geophysical Research Letters, 50, 20, American Geophysical Union (AGU), 17 Oct. 2023, [Peer-reviewed]
  Scientific journal, Abstract
  
  Relativistic Runaway Electrons Avalanches (RREAs) development depends on the applied electric field and the environment's air density. This dependency controls the RREA exponential growth length scale. The RREA development affects the bremsstrahlung excess occurring due to the passage of charged particles through the thundercloud's electric fields, the gamma‐ray glow. We used Monte Carlo simulations to develop an empirical model showing the RREA behavior in a realistic atmospheric density profile. The new formulation shows how the density variation modulates the electron population under electric field strengths near the RREA electric field threshold. The model limits the initial RREA altitude range as a function of the electric field strength. The new model is valid between ∼0.6 and ∼18 km, covering the relevant heights to investigate the generation of ground‐detected gamma‐ray glows.
• Termination of Downward‐Oriented Gamma‐Ray Glow by Normal‐Polarity In‐Cloud Discharge Activity
  Y. Wada; T. Wu; D. Wang; T. Enoto; K. Nakazawa; T. Morimoto; Y. Nakamura; T. Shinoda; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, 128, 15, American Geophysical Union (AGU), 29 Jul. 2023, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal, Abstract
  
  A gamma‐ray glow, a minute‐lasting burst of high‐energy photons from a thundercloud, was detected by ground‐based apparatus at Kanazawa University, Japan, in a winter thunderstorm on 18 December 2018. The gamma‐ray glow was quenched by a lightning flash within a brief time window of 40 ms. The lightning flash produced several low‐frequency (LF) E‐change pulses that were temporally coincident with the termination of the gamma‐ray glow, and that were located within 0.5 km from the observation site by the Fast Antenna Lightning Mapping Array. The LF pulses had the same polarity as a positive cloud‐to‐ground current and a normal‐polarity in‐cloud current. Since this polarity is against the upward electric field for producing the gamma‐ray glow (accelerating electrons to the ground), we infer that the glow was terminated by a normal‐polarity in‐cloud discharge activity between a middle negative layer and an upper positive layer.
• Lightning Mapping as a Probe of Electron Accelerator in Thunderclouds
  Yuuki Wada; Ting Wu; Daohong Wang; Teruaki Enoto; Kazuhiro Nakazawa; Takeshi Morimoto; Yoshitaka Nakamura; Taro Shinoda; Harufumi Tsuchiya
  Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023), 317, 317, Sissa Medialab, 25 Jul. 2023, [Lead author, Corresponding author]
  International conference proceedings
• Ambient Conditions of Winter Thunderstorms in Japan to Reproduce Observed Gamma‐Ray Glow Energy Spectra
  G. S. Diniz; Y. Wada; Y. Ohira; K. Nakazawa; M. Tsurumi; T. Enoto
  Journal of Geophysical Research: Atmospheres, 128, 10, American Geophysical Union (AGU), 12 May 2023, [Peer-reviewed]
  Scientific journal
• FGS, a multi-mission space gamma-ray spectrometer: Design optimization and first results
  Damien Pailot; Sylvie Blin; Eric Bréelle; Jérôme Carron; Claude Chapron; Moustapha Dekkali; Enzo Gagligiano; Philippe Laurent; Denis Perret; Nicole Vilmer; Yuuki Wada
  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1049, 168076, 168076, Elsevier BV, Apr. 2023, [Peer-reviewed], [Last author]
  Scientific journal
• Catalog of 525 sprites observed over Japan from September 2016 to March 2021
  Maomao Duan; Takanori Sakamoto; Teruaki Enoto; Yuuki Wada; Masashi Kamogawa; Koji Ito
  Heliyon, 9, 3, e13197, e13197, Elsevier BV, Mar. 2023, [Peer-reviewed]
  Scientific journal
• Synoptic meteorological conditions of gamma-ray glows in winter thunderstorms
  Yuuki Wada; Miwa Tsurumi; Syugo Hayashi; Koichiro Michimoto
  Progress in Earth and Planetary Science, 10, 1, Springer Science and Business Media LLC, 21 Feb. 2023, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal, Abstract
  
  The Gamma-ray Observation of Winter Thunderclouds collaboration has detected 70 gamma-ray glows, a high-energy phenomenon associated with thunderstorms, from October 2016 to March 2020 in Kanazawa and Komatsu, Ishikawa Prefecture, a central part of Japan facing the Sea of Japan. Based on surface and 500 hPa analyses, numerical prediction models, and surface and satellite observations, we classify their synoptic meteorological conditions into mainly three types. Most of the glow-detection cases were in west or west-southwest winds around the detection sites. Over half of the cases took place when a convex structure of surface pressure, often associated with a trough at 500 hPa, was formed along the coast of the Sea of Japan. Besides, we extract non-detection cases during winter thunderstorms in Kanazawa to compare with the glow-detection cases. While some of the non-detection cases have similar meteorological conditions as the glow-detection cases, most of the non-detection cases exhibited higher temperatures at the surface and 850 hPa, and higher − 10 $$^{\circ }$$C altitudes, which indicates that electrification occurs at higher altitudes than the glow-detection cases. Therefore, gamma rays might have been produced but were attenuated before reaching the ground and undetectable at sea level.
• On-ground calibrations of XGRE: An ultrafast gamma-ray spectrometer onboard the TARANIS mission for TGF studies
  Philippe Laurent; Jean-Pierre Baronick; Eric Bréelle; Ion Cojocari; Stéphane Colonges; Miles Lindsey-Clark; Damien Pailot; Yuuki Wada
  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1047, 167868, 167868, Elsevier BV, Feb. 2023, [Peer-reviewed], [Last author]
  Scientific journal
• Ideas for Radar Data Denoising and Fusion Based on Image Processing Techniques
  Daichi Kitahara; Yuuki Wada; Tomoaki Mega; Eiichi Yoshikawa; Hiroshi Kikuchi; Tomoo Ushio
  2023 35th General Assembly and Scientific Symposium of the International Union of Radio Science, URSI GASS 2023, 2023
  International conference proceedings
• High-precision time study of gamma-ray bursts during thunderstorms
  E. Kuriyama; M. Masubuchi; N. Koshikawa; R. Iwashita; A. Omata; T. Kanda; J. Kataoka; M. Tsurumi; G. Diniz; T. Enoto; Y. Wada
  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1045, 167515, 167515, Elsevier BV, Jan. 2023, [Peer-reviewed], [Last author]
  International conference proceedings
• Compton Camera Imaging of a Gamma-Ray Glow From a Thunderstorm
  E. Kuriyama; M. Masubuchi; N. Koshikawa; R. Iwashita; A. Omata; T. Kanda; J. Kataoka; M. Tsurumi; G. Diniz; T. Enoto; Y. Wada
  Geophysical Research Letters, 49, 19, 16 Oct. 2022, [Peer-reviewed], [Last author]
  Scientific journal
• Recent Progress on the Phased Array Weather Radar at X Band
  Tomoo Ushio; Dong-Kyun Kim; Philippe Baron; Yuuki Wada; Tomoaki Mega; Fumihiko Mizutani; Masakazu Wada; Eiichi Yoshikawa; Shinsuke Satoh; Hiroshi Hanado
  2022 IEEE Radar Conference (RadarConf22), IEEE, 21 Mar. 2022
  International conference proceedings
• Characteristics of Low‐Frequency Pulses Associated With Downward Terrestrial Gamma‐Ray Flashes
  Y. Wada; T. Morimoto; Y. Nakamura; T. Wu; T. Enoto; K. Nakazawa; T. Ushio; T. Yuasa; H. Tsuchiya
  Geophysical Research Letters, 49, 5, American Geophysical Union (AGU), 16 Mar. 2022, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Atmospheric Electron Spatial Range Extended by Thundercloud Electric Field Below the Relativistic Runaway Electron Avalanche Threshold
  G. Diniz; Y. Wada; Y. Ohira; K. Nakazawa; T. Enoto
  Journal of Geophysical Research: Atmospheres, 127, 3, American Geophysical Union (AGU), 16 Feb. 2022, [Peer-reviewed]
  Scientific journal
• Catalog of gamma-ray glows during four winter seasons in Japan
  Y. Wada; T. Matsumoto; T. Enoto; K. Nakazawa; T. Yuasa; Y. Furuta; D. Yonetoku; T. Sawano; G. Okada; H. Nanto; S. Hisadomi; Y. Tsuji; G. S. Diniz; K. Makishima; H. Tsuchiya
  Physical Review Research, 3, 4, American Physical Society ({APS}), 15 Nov. 2021, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Multiple Gamma‐ray Glows and a Downward TGF Observed from Nearby Thunderclouds
  S. Hisadomi; K. Nakazawa; Y. Wada; Y. Tsuji; T. Enoto; T. Shinoda; T. Morimoto; Y. Nakamura; T. Yuasa; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, 126, 18, 21 Aug. 2021, [Peer-reviewed]
  English, Scientific journal
• Meteorological Aspects of Gamma‐Ray Glows in Winter Thunderstorms
  Y. Wada; T. Enoto; M. Kubo; K. Nakazawa; T. Shinoda; D. Yonetoku; T. Sawano; T. Yuasa; T. Ushio; Y. Sato; G. S. Diniz; H. Tsuchiya
  Geophysical Research Letters, 48, 7, American Geophysical Union (AGU), 16 Apr. 2021, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Generation Possibility of Gamma‐Ray Glows Induced by Photonuclear Reactions
  G. S. Diniz; I. S. Ferreira; Y. Wada; T. Enoto
  Journal of Geophysical Research: Atmospheres, 126, 3, American Geophysical Union (AGU), 16 Feb. 2021, [Peer-reviewed]
  English, Scientific journal
• Photonuclear Reactions in Lightning II: Comparison between Observation and Simulation Model
  Y. Wada; T. Enoto; K. Nakazawa; T. Yuasa; Y. Furuta; H. Odaka; K. Makishima; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, American Geophysical Union ({AGU}), Oct. 2020, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Photonuclear Reactions in Lightning I: Verification and Modeling of Reaction and Propagation Processes
  Y. Wada; T. Enoto; K. Nakazawa; H. Odaka; Y. Furuta; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, American Geophysical Union ({AGU}), Oct. 2020, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Thundercloud Project: Exploring high-energy phenomena in thundercloud and lightning
  Takayuki Yuasa; Yuuki Wada; Teruaki Enoto; Yoshihiro Furuta; Harufumi Tsuchiya; Shohei Hisadomi; Yuna Tsuji; Kazufumi Okuda; Takahiro Matsumoto; Kazuhiro Nakazawa; Kazuo Makishima; Shoko Miyake; Yuko Ikkatai
  Progress of Theoretical and Experimental Physics, 2020, 10, Oxford University Press ({OUP}), 07 Aug. 2020, [Peer-reviewed]
  Scientific journal,
  We designed, developed, and deployed a distributed sensor network aiming at observing high-energy ionizing radiation, primarily gamma rays, from winter thunderclouds and lightning in coastal areas of Japan. Starting in 2015, we have installed, in total, more than 15 units of ground-based detector system in Ishikawa Prefecture and Niigata Prefecture, and accumulated 551 days of observation time in four winter seasons from late 2015 to early 2019. In this period, our system recorded 51 gamma-ray radiation events from thundercloud and lightning. Highlights of science results obtained from this unprecedented amount of data include the discovery of photonuclear reaction in lightning which produces neutrons and positrons along with gamma rays, and deeper insights into the life cycle of a particle-acceleration and gamma-ray-emitting region in a thundercloud. The present paper reviews objective, methodology, and results of our experiment, with a stress on its instrumentation.
• Photoneutron detection in lightning by gadolinium orthosilicate scintillators
  Y. Wada; K. Nakazawa; T. Enoto; Y. Furuta; T. Yuasa; K. Makishima; H. Tsuchiya
  Physical Review D, 101, 10, American Physical Society (APS), 29 May 2020, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• High Peak‐Current Lightning Discharges Associated With Downward Terrestrial Gamma‐Ray Flashes
  Y. Wada; T. Enoto; Y. Nakamura; T. Morimoto; M. Sato; T. Ushio; K. Nakazawa; T. Yuasa; D. Yonetoku; T. Sawano; M. Kamogawa; H. Sakai; Y. Furuta; K. Makishima; H. Tsuchiya
  Journal of Geophysical Research: Atmospheres, 125, 4, American Geophysical Union ({AGU}), Feb. 2020, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Gamma-ray glow preceding downward terrestrial gamma-ray flash
  Yuuki Wada; Teruaki Enoto; Yoshitaka Nakamura; Yoshihiro Furuta; Takayuki Yuasa; Kazuhiro Nakazawa; Takeshi Morimoto; Mitsuteru Sato; Takahiro Matsumoto; Daisuke Yonetoku; Tatsuya Sawano; Hideo Sakai; Masashi Kamogawa; Tomoo Ushio; Kazuo Makishima; Harufumi Tsuchiya
  Communications Physics, 2, 1, Springer Science and Business Media LLC, Dec. 2019, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Downward Terrestrial Gamma-Ray Flash Observed in a Winter Thunderstorm
  Y. Wada; T. Enoto; K. Nakazawa; Y. Furuta; T. Yuasa; Y. Nakamura; T. Morimoto; T. Matsumoto; K. Makishima; H. Tsuchiya
  Physical Review Letters, 123, 6, American Physical Society (APS), 07 Aug. 2019, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Gamma-ray observations at the coastal area of Japan Sea in winter seasons
  H. Tsuchiya; T. Enoto; Y. Wada; Y. Furuta; K. Nakazawa; T. Yuasa; D. Umemoto; K. Makishima; the GROWTH collaboration
  Proceedings of Science, 358, Sissa Medialab Srl, 2019
  English, International conference proceedings
• Mapping Observation Project of High-Energy Phenomena during Winter Thunderstorms in Japan
  Yuuki Wada; Teruaki Enoto; Yoshihiro Furuta; Kazuhiro Nakazawa; Takayuki Yuasa; Takahiro Matsumoto; Daigo Umemoto; Kazuo makishima; Harufumi Tsuchiya; the GROWTH collaboration
  TEPA (Thunderstorms and Elementary Particle Acceleration) 2018 conference proceedings, 15 Nov. 2018, [Lead author, Corresponding author]
  International conference proceedings, The Gamma-Ray Observation of Winter Thunderclouds (GROWTH) collaboration has been performing observation campaigns of high-energy radiation in coastal areas of Japan Sea. Winter thunderstorms in Japan have unique characteristics such as frequent positive-polarity discharges, large discharge current, and low cloud bases. These features allow us to observe both long-duration gamma-ray bursts and lightning-triggered short-duration bursts at sea level. In 2015, we started a mapping observation project using multiple detectors at several new observation sites. We have developed brand-new portable gamma-ray detectors and deployed in the Kanazawa and Komatsu areas as well as the existing site at Kashiwazaki. During three winter seasons from 2015, we have detected 27 long-duration bursts and 8 short-duration bursts. The improved observation network in Kashiwazaki enables us to discover that the short-duration bursts are attributed to atmospheric photonuclear reactions triggered by a downward terrestrial gamma-ray flash. Collaborating with electric -field and radio-band measurements, we have also revealed a relation between abrupt termination of a long-duration burst and a lightning discharge. We demonstrate that the mapping observation project has been providing us clues to understand high-energy atmospheric phenomena associated with thunderstorm activities.
• Termination of Electron Acceleration in Thundercloud by Intracloud/Intercloud Discharge
  Y. Wada; G. S. Bowers; T. Enoto; M. Kamogawa; Y. Nakamura; T. Morimoto; D. M. Smith; Y. Furuta; K. Nakazawa; T. Yuasa; A. Matsuki; M. Kubo; T. Tamagawa; K. Makishima; H. Tsuchiya
  Geophysical Research Letters, American Geophysical Union ({AGU}), 09 Jun. 2018, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• An estimation of the white dwarf mass in the Dwarf Nova GK Persei with NuSTAR observations of two states
  Yuuki Wada; Takayuki Yuasa; Kazuhiro Nakazawa; Kazuo Makishima; Takayuki Hayashi; Manabu Ishida
  Monthly Notices of the Royal Astronomical Society, 474, 2, 1564, 1571, Oxford University Press (OUP), 21 Feb. 2018, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Photonuclear reactions triggered by lightning discharge
  Teruaki Enoto; Yuuki Wada; Yoshihiro Furuta; Kazuhiro Nakazawa; Takayuki Yuasa; Kazufumi Okuda; Kazuo Makishima; Mitsuteru Sato; Yousuke Sato; Toshio Nakano; Daigo Umemoto; Harufumi Tsuchiya
  Nature, 551, 7681, 481, 484, Nov. 2017, [Peer-reviewed]
  English, Scientific journal
• NuSTAR Observations of the Dwarf Nova GK Persei in 2015: Comparison between Outburst and Quiescent Phases
  Yuuki Wada; Takayuki Yuasa; Kazuhiro Nakazawa; Kazuo Makishima; Takayuki Hayashi; Manabu Ishida
  20TH EUROPEAN WHITE DWARF WORKSHOP, 509, 509, 514, 2017, [Lead author, Corresponding author]
  English, International conference proceedings

• Development of a directional Cherenkov detector to measure the location of the electron acceleration region of lightning gamma ray flashes.
  馬場萌花; 大口真奈里; 安藤美唯; 中澤知洋; 大熊佳吾; 和田有希; WU Ting; 田中敦也; 大宮悠希; 伊藤大将; 西村悠太; 坂井晃生; 久富章平; WANG Daohong; 一方井祐子; 榎戸輝揚; 榎戸輝揚, 日本物理学会講演概要集(CD-ROM), 80, 1, 2025
• Development of a Cherenkov detector for estimating the direction of arrival of Terrestrial Gamma-ray Flash
  安藤美唯; 中澤知洋; 大口真奈里; 久富章平; 田中敦也; 大熊佳吾; 大宮悠希; 榎戸輝揚; 榎戸輝揚; 和田有希; 湯浅孝行; 伊藤大将; 西村悠太; 坂井晃生, 日本物理学会講演概要集(CD-ROM), 79, 1, 2024
• Direction measurements of the TGF on November 18, 2023 in Hokuriku
  大口真奈里; 安藤美唯; 中澤知洋; 大熊佳吾; 湯浅孝行; 和田有希; WU Ting; 田中敦也; 大宮悠希; 伊藤大将; 西村悠太; 坂井晃生; 久富章平; WANG Daohong; 一方井祐子; 榎戸輝揚; 榎戸輝揚, 日本地球惑星科学連合大会予稿集(Web), 2024, 2024
• Directional measurement of MeV gamma gays using the Si pixel detector Timepix3 with electron tracking and its application in winter Hokuriku TGF observation
  田中敦也; 中澤知洋; 大熊佳吾; 大宮悠希; 安藤美唯; 大口真奈里; 榎戸輝揚; 和田有希; 一方井祐子; WU Ting; WANG Daohong, 日本地球惑星科学連合大会予稿集(Web), 2024, 2024
• Development of a directional Cherenkov detector to measure the location of the electron acceleration region of lightning gamma ray flashes: 2
  大口真奈里; 安藤美唯; 中澤知洋; 中澤知洋; 大熊佳吾; 湯浅孝行; 和田有希; WU Ting; 田中敦也; 大宮悠希; 伊藤大将; 西村悠太; 坂井晃生; 久富章平; WANG Daohong; 一方井祐子; 榎戸輝揚; 榎戸輝揚, 日本物理学会講演概要集(CD-ROM), 79, 2, 2024
• Development of a directional Cherenkov detector to measure the location of the electron acceleration region of lightning gamma ray flashes
  安藤美唯; 中澤知洋; 大口真奈里; 久富章平; 大熊佳吾; 大宮悠希; 田中敦也; 榎戸輝揚; 榎戸輝揚; 和田有希; 湯浅孝行, 日本物理学会講演概要集(CD-ROM), 78, 2, 2023
• Development of Cherenkov detector for directional observation of sudden gamma rays associated with lightning discharges.
  安藤美唯; 中澤知洋; 大口真奈里; 久富章平; 大熊佳吾; 大宮悠希; 田中敦也; 榎戸輝揚; 榎戸輝揚; 和田有希; 湯浅孝行, 日本地球惑星科学連合大会予稿集(Web), 2023, 2023
• Gamma ray and radio wave analysis of five consecutive TGFs observed in Kanazawa, Japan on December 30, 2021
  大口真奈里; 中澤知洋; WU Ting; 和田有希; 大熊佳吾; WANG Daohong; 辻結菜; 大宮悠希; 安藤美唯; 榎戸輝揚; 篠田太郎, 日本地球惑星科学連合大会予稿集(Web), 2023, 2023
• A simple altitude measurement of the electron accelerator for lightning gamma rays in the Kanazawa area during the winter of 2022.
  田中敦也; 中澤知洋; 大熊佳吾; 大宮悠希; 安藤美唯; 大口真奈里; 榎戸輝揚; 和田有希; 一方井祐子; WU Ting; WANG Daohong, 日本地球惑星科学連合大会予稿集(Web), 2023, 2023
• Attempt to measure the location of lightning gamma ray glow and flash electron acceleration areas in the Kanazawa area during the winter of 2022.
  大口真奈里; 中澤知洋; 大熊佳吾; 大宮悠希; 安藤美唯; 田中敦也; 小林昌彦; 榎戸輝揚; 和田有希; 一方井祐子; WU Ting; WANG Daohong, 日本物理学会講演概要集(CD-ROM), 78, 2, 2023
• 10 MeV gamma-ray detector with direction sensitivity to observe Gamma-ray Flashes from Lightning
  中澤知洋; 大熊佳吾; 大宮悠希; 安藤美唯; 大口真奈里; 田中敦也; 高橋忠幸; 和田有希; 榎戸輝揚, 日本物理学会講演概要集(CD-ROM), 77, 2, 2022
• Analysis of two Gamma-ray Glows obtained with GOOSE detector aiming at altitude measurements during the winter of FY2020 and FY2021.
  大熊佳吾; 中澤知洋; 辻結菜; 大宮悠希; 安藤美唯; 久富章平; 榎戸輝揚; 和田有希; 湯浅孝行; 土屋晴文; 篠田太郎; DINIZ Gabriel; 山田真也; 鶴見美和; 鶴見美和, 日本地球惑星科学連合大会予稿集(Web), 2022, 2022
• ドローンを用いた雷雲直下での放射線観測の検討
  和田有希; 中村裕子; 榎戸輝揚, 大気電気学会誌(Web), 16, 1, 2022
• シチズンサイエンスを活用した金沢での放射線マッピング「雷雲プロジェクト」
  榎戸輝揚; 鶴見美和; 一方井祐子; GABRIEL Diniz; 三宅晶子; 富岡大; 中澤知洋; 和田有希; 久富富平; 辻結菜; 森本健志; 中村佳敬; 鴨川仁; 沼澤正樹; 加藤陽; 湯浅孝行; 土屋晴文, 大気電気学会誌(Web), 16, 1, 2022
• Gamma-ray Observation of Winter Thunderclouds: Comparison of three Gamma-ray Glows observed by collimator detector
  大熊佳吾; 中澤知洋; 辻結菜; 大宮悠希; 安藤美唯; 田中敦也; 大口真奈里; 榎戸輝揚; 和田有希; 湯浅孝行; 土屋晴文; 篠田太郎; DINIZ Gabriel; 山田真也; 鶴見美和; 鶴見美和; 一方井祐子, 日本物理学会講演概要集(CD-ROM), 77, 2, 2022
• Observation and analysis of thundercloud gamma-ray glows in fiscal year 2021 by the Citizen Science “Thundercloud Project“
  鶴見美和; 鶴見美和; 榎戸輝揚; 一方井裕子; DINIZ Gabriel Sousa; 高垣徹; 三宅晶子; 富岡大; 中澤知洋; 和田有希; 篠田太郎; 森本健志; 中村佳敬; 鴨川仁; 土屋晴文, 日本地球惑星科学連合大会予稿集(Web), 2022, 2022
• Positron observations in high-energy atmospheric physics
  和田 有希, 陽電子科学 = Positron sciences, 17, 15, 21, Sep. 2021, [Peer-reviewed], [Invited], [Lead author, Corresponding author]
  日本陽電子科学会, Japanese, Introduction scientific journal
• Gamma-ray Observation of Winter Thundercloud: Attempt to measure altitude in electron acceleration range in 2020
  久富章平; 中澤知洋; 辻結菜; 伊神勇作; 小谷大貴; 榎戸輝揚; 和田有希; 湯浅孝行; 古田禄大; 土屋晴文; 一方井祐子; 三宅晶子, 日本物理学会講演概要集(CD-ROM), 76, 1, 2021
• Performance verification and acceptance test of CoGaMo detectors of the thundercloud project
  富岡大; 三宅晶子; 鶴見美和; 鶴見美和; 榎戸輝揚; 沼澤正樹; 和田有希; 中澤知洋; 一方井祐子; 高垣徹, 電気学会東京支部茨城支所研究発表会講演予稿集, 29th (CD-ROM), 2021
• Citizen science ”Thundercloud project” for mapping observations of gamma rays from thunderstorms
  榎戸輝揚; 一方井祐子; 和田有希; DINIZ Gabriel; 沼澤正樹; 加藤陽; 三宅晶子; 中澤知洋; 久富富平; 辻結菜; 湯浅孝行; 土屋晴文; 森本健志; 中村佳敬; 鴨川仁, 日本地球惑星科学連合大会予稿集(Web), 2021, 2021
• 日本天文学会早川幸男基金による渡航報告書 : The EGU General Assembly 2019 etc.
  和田 有希, 天文月報 = The astronomical herald, 113, 12, 825, 827, Dec. 2020, [Lead author, Corresponding author]
  日本天文学会, Japanese, Introduction scientific journal
• Thundercloud Project: Mapping Observation of High-Energy Atmospheric Phenomena of Lightning and Thunderstorms using the Citizen Science Framework
  榎戸輝揚; 和田有希; 久富富平; 辻結菜; 中澤知洋; 湯浅孝行; 一方井裕子; 三宅晶子; 土屋晴文, 日本物理学会講演概要集(CD-ROM), 75, 2, 2020
• Gamma-ray Observation of Winter Thunderclouds: Long-distance tracking of long burst with monitoring posts
  辻結菜; 中澤知洋; 久富章平; FABIANI Alexia; 榎戸輝揚; 和田有希; 和田有希; 湯浅考行; 古田禄大; 土屋晴文; 楳本大悟; 篠田太郎; 加藤雅也, 日本地球惑星科学連合大会予稿集(Web), 2020, 2020
• Gamma-ray Observation of Winter Thunderclouds: Long-distance tracking of gamma-ray glow observed in December 2014 with monitoring posts
  辻結菜; 中澤知洋; 久富章平; 榎戸輝揚; 和田有希; 湯浅孝行; 古田禄大; 土屋晴文; 楳本大悟; 篠田太郎; 加藤雅也, 日本物理学会講演概要集(CD-ROM), 75, 2, 2020
• Gamma-ray Observation of Winter Thundercloud: Progress of multi-point observation in 2019
  久富章平; 中澤知洋; 辻結菜; FABIANI Alexia; 榎戸輝揚; 和田有希; 和田有希; 湯浅孝行; 古田禄大; 土屋晴文; 一方井祐子; 三宅晶子, 日本物理学会講演概要集(CD-ROM), 75, 1, 2020
• Gamma-ray Observation of Winter Thunderclouds: the progress of multi - point observation in 2019
  久富章平; 中澤知洋; 辻結菜; FABIANI Alexia; 榎戸輝揚; 和田有希; 和田有希; 湯浅孝行; 古田禄大; 土屋晴文; 一方井祐子; 三宅晶子, 日本地球惑星科学連合大会予稿集(Web), 2020, 2020
• multiple long burst that terminated by lightning on January 2020
  久富章平; 中澤知洋; 辻結菜; 榎戸輝揚; 和田有希; 湯浅孝行; 土屋晴文; 篠田太郎; 一方井祐子; 三宅晶子, 日本物理学会講演概要集(CD-ROM), 75, 2, 2020
• カミナリは「天然の加速器」か? – 冬の雷で原子核反応を発見 -
  和田有希, ガリレオ工房通信, 376, 8, 11, Sep. 2019, [Invited], [Lead author, Corresponding author]
  Introduction other
• 雷が引き起こす原子核反応 – 冬の北陸が舞台の高エネルギー大気物理学 -
  和田有希, じっきょう理科資料, 85, 18, 22, Apr. 2019, [Invited], [Lead author, Corresponding author]
  Introduction commerce magazine
• High-Energy Atmospheric Phenomena Initiated by Lightning
  Enoto Teruaki; Wada Yuuki; Tsuchiya Harufumi, Butsuri, 74, 4, 192, 200, Apr. 2019, [Invited]
  

  Powerful and low-altitude winter thunderstorms in Japan provide an ideal environment to observe the high-energy atmospheric phenomena. High-energy photons have been recorded with a time scale of a minute associated with passages of thunderstorms, called "long bursts" or "gamma-ray glow". These are bremsstrahlung radiation from relativistic electrons accelerated in strong electric field of thunderclouds. Lightning discharges also accelerate electrons and radiate high-energy gamma-rays, called "terrestrial gamma-ray flashes" when observed with satellites on orbit. Ground-based measurements have recently revealed that such gamma-rays collides with atomic nuclei of atmospheric nitrogen and oxygen, and can trigger photonuclear reaction. Such a radiation event has been observed as "short bursts" from lightning in Japan.

  , The Physical Society of Japan, Japanese, Introduction scientific journal
• X線による強磁場激変星の観測
  和田 有希, 天界 = The heavens, 100, 1125, 45, 49, Feb. 2019, [Invited], [Lead author, Corresponding author]
  東亜天文学会, Japanese, Introduction scientific journal
• カミナリ雲の中に隠れた天然の加速器の破壊
  和田有希; 中澤知洋, 東京大学理学部ニュース, 50, 6, Sep. 2018, [Lead author, Corresponding author]
  Introduction research institution
• 雷による光核反応の発見
  和田有希; 榎戸輝揚, Isotope News, 758, 28, 31, Aug. 2018, [Invited], [Lead author, Corresponding author]
  Introduction scientific journal
• 雷が雲の中に隠れた天然の加速器を破壊した！？
  和田有希, academist Journal, May 2018, [Lead author, Corresponding author]
  Introduction commerce magazine
• 地上と宇宙から探る雷放電に同期する突発ガンマ線観測への取り組み
  中澤知洋; 榎戸輝揚; 和田有希; 和田有希; 古田禄大; 松元崇弘; 春日知明; 奥田和史; 湯浅孝行; 中野俊男; 楳本大悟; 加藤博; 牧島一夫; 佐藤光輝; 佐藤陽祐; 土屋晴文, 日本天文学会年会講演予稿集, 2018, 2018
• 日本海沿岸における冬の雷や雷雲に伴う放射線観測
  土屋晴文; 榎戸輝揚; 和田有希; 和田有希; 古田禄大; 中澤知洋; 湯浅孝行; 奥田和史; 牧島一夫; 中野俊男; 楳本大悟, 日本原子力学会春の年会予稿集(CD-ROM), 2018, 2018
• Triggering of photonuclear reactions by a lightning discharge
  Enoto Teruaki; Nakano Toshio; Umemoto Daigo; Tsuchiya Harufumi; Wada Yuuki; Furuta Yoshihiro; Nakazawa Kazuhiro; Yuasa Takayuki; Okuda Kazufumi; Makishima Kazuo; Sato Mitsuteru; Sato Yousuke, Meeting Abstracts of the Physical Society of Japan, 73, 176, 176, 2018
  The Physical Society of Japan, Japanese
• Discovery of photonuclear reactions triggered by lightning: interpretation of observed data by simulations
  Furuta Yoshihiro; Nakano Toshio; Umemoto Daigo; Tsuchiya Harufumi; Wada Yuuki; Enoto Teruaki; Nakazawa Kazuhiro; Yuasa Takayuki; Okuda Kazufumi; Makishima Kazuo; Sato Mitsuteru; Sato Yousuke, Meeting Abstracts of the Physical Society of Japan, 73, 423, 423, 2018
  The Physical Society of Japan, Japanese
• Discovery of photonuclear reactions triggered by lightning discharge: On-ground detection of neutrons and positrons
  Wada Yuuki; Nakano Toshio; Suzuki Hiromasa; Umemoto Daigo; Tsuchiya Harufumi; Furuta Yoshihiro; Enoto Teruaki; Nakazawa Kazuhiro; Yuasa Takayuki; Okuda Kazufumi; Makishima Kazuo; Sato Mitsuteru; Sato Yousuke, Meeting Abstracts of the Physical Society of Japan, 73, 422, 422, 2018
  The Physical Society of Japan, Japanese
• The analysis of gamma ray from winter thundercloud in Kanazawa between 2015 and 2017
  Matsumoto Takahiro; Bamba Aya; Yonetoku Daisuke; Sawano Tatsuya; Wada Yuuki; Furuta Yoshihiro; Nakazawa Kazuhiro; Enoto Teruaki; Yuasa Takayuki; Makishima Kazuo; Tsuchiya Harufumi; Odaka Hirokazu, Meeting Abstracts of the Physical Society of Japan, 73, 134, 134, 2018
  The Physical Society of Japan, Japanese
• 雷雲ガンマ線の地上観測の現状と2017年のGROWTH実験計画
  中澤知洋; 榎戸輝揚; 和田有希; 古田禄大; 楳本大悟; 清野愛海; 樋口裕真; 湯浅孝行; 土屋晴文; 牧島一夫; 中野俊男, 日本物理学会講演概要集(CD-ROM), 72, 2, 2017
• Gamma-ray Observation of Accelerated Electrons in the Thunderstorm Electric Fields: Development of Data Acquisition System and Operation of Multipoint Observation in Hokuriku
  Wada Y.; Makishima K.; Kamogawa M.; Takita M.; Yonetoku D.; Sawano T.; Watarai K.; Yoneguchi K.; Kimura K.; Kitano K.; the GROWTH collaboration collaboration; Enoto T.; Yuasa T.; Nakazawa K.; Tsuchiya H.; Nakano T.; Okuda K.; Furuta Y.; Umemoto D., Meeting Abstracts of the Physical Society of Japan, 72, 503, 503, 2017
  

  雷雲ガンマ線の観測プロジェクトは2015年度より多地点によるマッピング観測を目指し、石川県でも展開を進めている。初年度の運用実績や成果を元にしてADC/FPGAによる読み出し系の改良を中心に開発を行い、小型ガンマ線検出器の台数を増やしつつある。これらの検出器は金沢市内、小松市内、及び柏崎刈羽原発内に設置し、マッピング観測を本格的に開始している。本講演では小型検出器の開発状況、および今年度の運用状況・成果について報告する。

  , The Physical Society of Japan, Japanese
• Gamma-ray Observation of Accelerated Electrons in the Thunderstorm Electric Fields: New Development to A Multipoint Observation Network
  Enoto T.; Makishima K.; Kamogawa M.; Takita M.; Yonetoku D.; Sawano T.; Watarai K.; Yoneguchi K.; Kimura K.; Kitano K.; the GROWTH collaboration collaboration; Wada Y.; Yuasa T.; Nakazawa K.; Tsuchiya H.; Nakano T.; Okuda K.; Furuta Y.; Umemoto D., Meeting Abstracts of the Physical Society of Japan, 72, 502, 502, 2017
  

  雷雲内の強電場で加速された電子からの制動放射ガンマ線を観測するプロジェクトは、2006年に柏崎で観測を開始して以来10年になり、観測事例も蓄積され、基本的な描像は確立しつつある。しかし、電子の加速領域の大きさや継続時間はこれまでの定点観測では把握が難しかったため、石川県内の複数の学校の屋上に、小型で低消費電力の放射線検出器を設置し、マッピング観測を新たに開始した。多地点観測への新展開プロジェクトの狙いと現状を報告する。

  , The Physical Society of Japan, Japanese
• GROWTH experiment : Deployment of collimator detectors to measure angular distribution of gamma-rays from thunderclouds.
  Okuda Kazufumi; Makishima Kazuo; the GROWTH collaboration collaboration; Nakazawa Kazuhiro; Furuta Yoshihiro; Wada Yuuki; Yuasa Takayuki; Enoto Teruaki; Suzuki Hiromasa; Umemoto Daigo; Tsuchiya Harufumi, Meeting Abstracts of the Physical Society of Japan, 72, 501, 501, 2017
  

  我々は10年にわたり新潟県柏崎刈羽原発内に検出器を設置して雷雲由来のガンマ線を測定し，雷雲内の粒子加速機構の解明を目指してきた。本年度、我々はコリメーターを用いることで方向に対し感度を持つ検出器を新たに設置した。本講演ではその運用成果について報告する。

  , The Physical Society of Japan, Japanese
• Compilation of 10 years of winter thundercloud gamma-ray observation
  Umemoto D.; Kawaharada M.; Kitaguchi T.; Iwata K.; Kato H.; Kokubun H.; Makishima K.; Nakazawa K.; Tsuchiya H.; Enoto T.; Yuasa T.; Furuta Y.; Okuda K.; Wada Y.; Tamagawa T.; Okano M., Meeting Abstracts of the Physical Society of Japan, 72, 499, 499, 2017
  

  我々はこれまで10年にわたり新潟県柏崎刈羽原発内に検出器を設置して雷雲由来のガンマ線を観測し、放射機構の解明を目指してきた。2014,2015年に観測された事象の空間分布を調べたところ、強度変動の主原因が雷雲の移動で、放射が到達した領域が1 kmスケールの楕円であることが確定し、2分程度にわたり放射が持続したことも判明した。これに基づき、これまで観測された全事象について系統的なスペクトル・カウント数の時系列解析を行った。

  , The Physical Society of Japan, Japanese
• GROWTH experiment: Interpretation of diffuse gamma-ray emissions from thunderclouds using Monte Carlo simulation
  Furuta Y.; the GROWTH collaboration collaboration; Umemoto D.; Nakazawa K.; Okuda K.; Wada Y.; Enoto T.; Yuasa T.; Tsuchiya H.; Makishima K., Meeting Abstracts of the Physical Society of Japan, 72, 500, 500, 2017
  

  我々は雷雲内の粒子加速機構の解明を目指し，新潟県柏崎刈羽原発内で雷雲由来ガンマ線の測定を継続している。2014–15年冬には約100秒間に10万カウント前後という高統計のガンマ線増大現象が複数観測され，地上に届くガンマ線放射の広がりの大きさや形状が判明した。本講演ではモンテカルロシミュレーションを用いて，電場加速された電子が地上にもたらす制動放射ガンマ線の分布をモデル化し，実データと比較することで，加速現場の高度や加速方向の広がりを推定する。

  , The Physical Society of Japan, Japanese
• Construction of gamma-ray emission model from thunderclouds using Monte Carlo simulation
  Furuta Y.; Nakazawa K.; Wada Y.; Umemoto D.; Enoto T.; Yuasa T.; Tsuchiya H.; Makishima K.; the GROWTH collaboration, Meeting Abstracts of the Physical Society of Japan, 72, 412, 412, 2017
  The Physical Society of Japan, Japanese
• 21pAZ-12 Miniaturization of detecting systems and its operation in Hokuriku 2015 for a multipoint observation of gamma rays from thunderclouds
  Wada Y.; Enoto T.; Yuasa T.; Nakano T.; Nakazawa K.; Okuda K.; Furuta Y.; Umemoto D.; Tsuchiya H., Meeting Abstracts of the Physical Society of Japan, 71, 500, 500, 2016
  The Physical Society of Japan, Japanese
• 21pAZ-13 GROWTH experiment : Compiled analysis of all thundercloud gamma-ray data from detector at Kashiwazaki-Kariwa nuclear power plant obtained during 2006 and 2015
  Umemoto D.; Makishima K.; Tsuchiya H.; Nakazawa K.; Furuta Y.; Okuda K.; Wada Y.; Kato H.; Yuasa T.; Enoto T., Meeting Abstracts of the Physical Society of Japan, 71, 501, 501, 2016
  The Physical Society of Japan, Japanese
• NuSTAR observations of the Dwarf Nova GK Persei in 2015: comparison between outburst and quiescence
  Wada Yuuki; Yuasa Takayuki; Nakazawa Kazuhiro; Makishima Kazuo; Hayashi Takayuki; Ishida Manabu, Meeting Abstracts of the Physical Society of Japan, 71, 391, 391, 2016
  

  GK Persei は強磁場白色矮星 (WD) と恒星との連星系である。恒星からのガスがWDの周りで降着円盤を形成し、その内縁から磁場に沿ってWDの磁極付近へ降着柱を形成しながら降着する。またGK Perseiは約2年に一度、2ヶ月間にわたる矮新星爆発を起こす。我々はNuSTARによる2015年3月の矮新星爆発と同9月の静穏期におけるX線観測データを解析した。本講演では2つの観測での降着柱の最大温度と光度の変化から、WDの質量、降着円盤の内縁半径や降着柱内の衝撃波高さといったWDのジオメトリについて議論する。

  , The Physical Society of Japan, Japanese
• フランス航空ツアー体験記(その2)(<連載>空と宇宙に学ぶ/学生の挑戦,学生会員の広場)
  宮崎 俊平; 和田 有希; 天田 直弥; 加茂 舜平; 藤田 彬; 橋本 那音; 高居 明弘, 日本航空宇宙学会誌, 63, 6, 212, 213, 2015
  一般社団法人 日本航空宇宙学会, Japanese
• フランス航空ツアー体験記(その1)(<連載>空と宇宙に学ぶ/学生の挑戦,学生会員の広場)
  和田 有希; 宮崎 俊平; 天田 直弥; 加茂 舜平; 藤田 彬; 橋本 那音; 高居 明弘, 日本航空宇宙学会誌, 63, 5, 167, 168, 2015, [Lead author]
  一般社団法人 日本航空宇宙学会, Japanese
• 28pJS-5 超伝導物質の生成条件について(口頭発表,日本物理学会第5回Jr.セッション)
  和田 有希; 赤堀 圭一; 野中 喬文; 山本 晃義, 日本物理學會誌, 64, 3, 135, 135, 05 Mar. 2009
  一般社団法人日本物理学会, Japanese

• 〔Major achievements〕Observational Studies of Photonuclear Reactions Triggered by Lightning Discharges (Springer Theses)
  Yuuki Wada
  Springer Nature, 2021, [Single work]

• Possibilities and Future Prospects of High-altitude Meteorological Sensing by Muons
  Yuuki Wada
  Workshop on Recent Advances in Muography, Mar. 2024, English, Invited oral presentation
  [Invited]
• Multi-Frequency Observation of Downward Terrestrial Gamma-ray Flashes in Winter Thunderstorms
  Yuuki Wada, Takeshi Morimoto, Yoshitaka Nakamura, Teruaki Enoto, Hiroshi Kikuchi, Eiichi Yoshikawa, Tomoo Ushio
  URSI GASS 2023, Aug. 2023, English, Invited oral presentation
  [Invited]
• 北陸冬季雷におけるガンマ線グロー発生時の大気電場変動
  和田有希; 鴨川仁; 久保守; 榎戸輝揚; 林修吾; 澤野達哉; 米徳大輔; 土屋晴文
  日本地球惑星科学連合大会, May 2023, Japanese, Invited oral presentation
  [Invited]
• High-energy Atmospheric Physics in Winter Thunderstorms of Japan
  Yuuki Wada
  AGU Atmospheric and Space Electricity Early Career Event Vol.2, May 2023, Public discourse
  [Invited]
• High-energy Atmospheric Physics in Winter Thunderstorms of Japan
  Yuuki Wada
  AGU Fall Meeting 2022, Dec. 2022, English, Invited oral presentation
  [Invited]
• 高エネルギー大気物理学の新展開
  和田有希
  第6回 宇宙素粒子若手の会 秋の研究会, Nov. 2021, Japanese, Invited oral presentation
  [Invited]
• 雷放電による光核反応の観測的研究
  和田有希
  日本物理学会 第76回年次大会, Mar. 2021, Japanese, Invited oral presentation
  [Invited]
• 高エネルギー大気物理学におけるGeant4 – 検出器応答から大気中における粒子輸送と光核反応まで -
  和田有希
  Geant4初心者講習会・研究会, Nov. 2019, Japanese, Invited oral presentation
  [Invited]
• X-ray Views of the Dwarf Nova GK Persei
  Yuuki Wada; Kazuhiro Nakazawa; Kazuo Makishima; Takayuki Yuasa; Takayuki Hayashi; Manabu Ishida
  The Golden Age of Cataclysmic Variables and Related Objects – V, Sep. 2019, English, Invited oral presentation
  [Invited]
• Recent Updates from Mapping Observation of High-energy phenomena In Japanese Winter Thunderstorms
  Yuuki Wada, Teruaki Enoto, Yoshihiro Furuta, Kazuhiro Nakazawa, Takayuki Yuasa, Takahiro Matsumoto, Daigo Umemoto, Kazuo Makishima, Harufumi Tsuchiya
  Thunderstorms and Elementary Particle Acceleration (TEPA) 2018, Sep. 2018, English, Invited oral presentation
  [Invited]
• X-ray estimates of white dwarf masses in magnetic cataclysmic variables
  Yuuki Wada; Takayuki Yuasa; Kazuhiro Nakazawa; Kazuo Makishima; Takayuki Hayashi; Manabu Ishida
  15th Marcel Grossmann Meeting, Jul. 2018, English, Invited oral presentation
  [Invited]
• 雷放電によって破壊された雷雲内の電場加速機構
  和田有希, Gregory S. Bowers, 榎戸輝揚, 鴨川仁, 中村佳敬, 森本健志, David M. Smith, 古田禄大, 中澤知洋, 湯浅孝行, 玉川徹, 牧島一夫, 土屋晴文
  雷雲と宇宙線の相互作用に伴う高エネルギー現象, Mar. 2018, Japanese, Invited oral presentation
  [Invited]

• Jun. 2022 - Present
  日本気象学会
• Oct. 2021 - Present
  日本気象予報士会
• Jul. 2021 - Present
  日本大気電気学会
• Jul. 2019 - Present
  High Energy AstroPhysics Association in Japan
• Aug. 2017 - Present
  American Geophysical Union
• Jan. 2017 - Present
  Japan Geoscience Union
• Dec. 2015 - Present
  Japan Physical Society
• Dec. 2018 - Mar. 2020
  Atomic Energy Society of Japan
• Jun. 2015 - Mar. 2020
  Astronomical Society of Japan
• Jan. 2018 - Dec. 2019
  European Geoscience Union

• 次世代の降水観測に向けた気象レーダーの進化
  創発的研究支援事業
  Oct. 2025 - Mar. 2029
  国立研究開発法人科学技術振興機構, Principal investigator, JPMJFR241K
• 最先端の観測技術と数値実験の融合で明らかにする雷雲の内部構造
  科学研究費助成事業
  Apr. 2024 - Mar. 2029
  佐藤 陽祐; 芳原 容英; 林 修吾; 吉田 龍二; 菊池 博史; 和田 有希
  日本学術振興会, 基盤研究(A), 北海道大学, 24H00257
• 多波長観測による地球ガンマ線フラッシュの解明
  科学研究費助成事業
  Apr. 2025 - Mar. 2028
  和田 有希, ウ ティン, 森本 健志
  日本学術振興会, 基盤研究(B), 大阪大学, 25K01013
• 宇宙線ミューオンによる高層大気圧のリモートセンシング
  科学研究費助成事業
  Apr. 2025 - Mar. 2027
  和田 有希
  日本学術振興会, 学術変革領域研究(A), 大阪大学, 25H02082
• 2重偏波フェーズドアレイレーダネットワークに関する研究
  科学研究費助成事業
  Apr. 2024 - Mar. 2027
  牛尾 知雄; バロン フィリップ; 川村 誠治; 黒田 大貴; 菊池 博史; 和田 有希; 重 尚一; 北原 大地
  日本学術振興会, 基盤研究(A), 大阪大学, 24H00272
• Development of lightning prediction technology by muon observations
  Grants-in-Aid for Scientific Research
  Apr. 2022 - Mar. 2025
  和田 有希
  Japan Society for the Promotion of Science, Grant-in-Aid for Early-Career Scientists, Osaka University, 22K14453
• 科学的モデリングによる気象レーダの高解像度化
  科学研究費助成事業
  Apr. 2021 - Mar. 2025
  牛尾 知雄; 黒田 大貴; 楠 研一; 菊池 博史; 和田 有希; 吉川 栄一; 北原 大地
  日本学術振興会, 基盤研究(B), 大阪大学, 21H01592
• Nonthermal processes in lightning and thunderclouds revealed by observations at ground and high mountains
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
  01 Apr. 2021 - 31 Mar. 2024
  土屋 晴文; 川田 和正; 和田 有希; 小井 辰巳
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Japan Atomic Energy Agency, 21H01116
• フェーズドアレイ気象レーダーによるドローン・空飛ぶクルマの検知能力実証
  戦略的情報通信研究開発推進事業 (SCOPE)
  Jun. 2023 - Mar. 2024
  和田有希 牛尾知雄 牛腸正則 花土弘 佐藤晋介 川村誠治
  総務省, 令和5年度電波有効利用促進型研究開発 (先進的電波有効利用型) フェーズⅠ, Principal investigator
• Studies on electron acceleration and multiplication in lightning by a ground-based array of small dosimeters
  Grants-in-Aid for Scientific Research
  Sep. 2020 - Mar. 2022
  和田 有希
  本研究では北陸地方の日本海沿岸部で発生する冬の雷に着目し、雷放電から放出されるガンマ線である「地球ガンマ線フラッシュ」を観測することで、雷における強電場領域がどのように電子を相対論的なエネルギーまで加速・増幅しているか、を明らかにする。北陸冬季雷は雷雲の発達高度が低いため、発生したガンマ線が大気による減衰をあまり受けずに地上に到達するため、地上観測の絶好のターゲットである。2020年度はガンマ線を観測する小型の線量計の開発に着手した。線量計の基礎設計を行い、プラスチックシンチレータと光電子増倍管を組み合わせることに決めた後、電子回路系基板を設計、プロトタイプの制作を行った。制作したプロトタイプについては放射線源やLEDなどの照射による性能評価を行った後、改良に向けた開発や試験などを進めた。
  また石川県金沢市を中心にガンマ線検出器の2020年度の設置を進め、2020年11月以降に観測を開始しており、観測データの蓄積を進めた。加えて雷放電の種となる雷雲から放出されるガンマ線の事象についても解析を進め、雷放電の観測ネットワークや国土交通省のXバンド気象レーダー、降水粒子判別器などのデータを比較することで、雷雲からガンマ線が放出される時の気象条件や、上空の降水粒子分布を明らかにし、論文として出版した (Wada et al., 2021, Meteorological aspects of gamma-ray glows in winter thunderstorms, Geophysical Research Letters, 48, e2020GL091910)。
  Japan Society for the Promotion of Science, Grant-in-Aid for Research Activity Start-up, Institute of Physical and Chemical Research, 20K22354
• Study of particle acceleration and high-energy phenomena in strong electric field of lightning strikes
  Grants-in-Aid for Scientific Research
  Apr. 2018 - Mar. 2020
  和田 有希
  雷放電からは10 MeVを超えるガンマ線が放出され、地球ガンマ線フラッシュ (terrestrial gamma-ray flash: TGF) と呼ばれている。これは雷放電で生じた強力な電場が大気中で電子を相対論的なエネルギーまで加速している証拠である。一方でTGFが濃密な大気中で効率よく電子を加速・増幅するメカニズムは未解明である。そこで私は北陸地方の冬季に発生する雷放電を対象としてガンマ線の地上観測を行い、TGFやTGFが光核反応によって生成する中性子・陽電子を観測してきた。
  2019年度は石川県・新潟県におけるガンマ線検出器の拡充を行うとともに、雷放電の電波観測グループとの共同研究を推進し、TGFを多角的に研究する体制を構築した。その成果は3本の主著論文として出版した。2018年1月の事例では、雷放電の前に1分間ほどロングバーストと呼ばれるガンマ線が雷雲から放出されており、ロングバーストの発生場所からTGFが発生したことを明らかにした。このことから、ロングバーストを生じさせる雷雲内の強い電場領域がTGFの発生源となっている可能性を提示した (Wada et al., Comms. Phys., 2019)。2017年11月の事例では、通常の検出器では完全に飽和してしまったTGFによる地上の粒子フラックスを、原子力発電所の電離箱高線量計を用いて吸収線量として測定し、TGFの規模や発生高度を推定した (Wada et al., Phys. Rev. Lett., 2019)。また金沢市で観測した2事例においては、TGFがenergetic in-cloud pulseと呼ばれる特殊な雷放電に同期していたことを突き止めた (Wada et al., JGR Atmos., 2020)。このように北陸地方の恵まれた観測環境と多波長による観測で高エネルギー大気物理学を開拓した。
  Japan Society for the Promotion of Science, Grant-in-Aid for JSPS Fellows, The University of Tokyo, 18J13355