Faculty Profiles - MIYAKE Fusa

Papers - MIYAKE Fusa

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Investigation of extreme solar energetic particle events in the past 10,000years

Proceedings of the 23rd Japanese Symposium on Accelerator Mass Spectrometry JAMS-23 2023

Modeling the Transport and Deposition of <sup>10</sup> Be Produced by the Strongest Solar Proton Event During the Holocene Reviewed Open Access

T. C. Spiegl, S. Yoden, U. Langematz, T. Sato, R. Chhin, S. Noda, F. Miyake, K. Kusano, K. Schaar, M. Kunze

Journal of Geophysical Research: Atmospheres Vol. 127 ( 13 ) 2022.7

Language：English Publishing type：Research paper (scientific journal) Publisher：American Geophysical Union (AGU)

Prominent excursions in the number of cosmogenic nuclides (e.g., 10Be) around 774 CE/775 document the most severe solar proton event (SPE) throughout the Holocene. Its manifestation in ice cores is valuable for geochronology, but also for solar-terrestrial physics and climate modeling. Using the ECHAM/MESSy Atmospheric Chemistry (EMAC) climate model in combination with the Warning System for Aviation Exposure to SEP (WASAVIES), we investigate the transport, mixing, and deposition of the cosmogenic nuclide 10Be produced by the 774 CE/775 SPE. By comparing the model results to the reconstructed 10Be time series from four ice core records, we study the atmospheric pathways of 10Be from its stratospheric source to its sink at Earth's surface. The reconstructed post-SPE evolution of the 10Be surface fluxes at the ice core sites is well captured by the model. The downward transport of the 10Be atoms is controlled by the Brewer-Dobson circulation in the stratosphere and cross-tropopause transport via tropopause folds or large-scale sinking. Clear hemispheric differences in the transport and deposition processes are identified. In both polar regions the 10Be surface fluxes peak in summertime, with a larger influence of wet deposition on the seasonal 10Be surface flux in Greenland than in Antarctica. Differences in the peak 10Be surface flux following the 774 CE/775 SPE at the drilling sites are explained by specific meteorological conditions depending on the geographic locations of the sites.

DOI： 10.1029/2021JD035658

Open Access

Web of Science

Scopus

Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2021JD035658

High‐Resolution 10 Be and 36 Cl Data from the Antarctic Dome Fuji Ice Core (∼100 years around 5480 BCE): An Unusual Grand Solar Minimum Occurrence? Reviewed

K. Kanzawa, F. Miyake, K. Horiuchi, K. Sasa, K. Takano, M. Matsumura, T. Takahashi, Y. Motizuki, K. Takahashi, Y. Nakai, K. Ohtani, Y. Tada, Y. Ochiai, H. Motoyama, H. Matsuzaki, A. Yamazaki, Y. Muramatsu, T. Yamagata

Journal of Geophysical Research: Space Physics Vol. 126 ( 10 ) 2021.10

Language：English Publishing type：Research paper (scientific journal) Publisher：American Geophysical Union (AGU)

Cosmogenic nuclides in tree rings and polar ice cores record the information of past cosmic ray intensities and solar activities. A large 14C increase over 10 years has been discovered around 5480 BCE. The 14C variations in this event differ from those of other short-term cosmic ray events and typical grand solar minima. To elucidate the cause of the 14C increase around 5480 BCE, we measured the 10Be and 36Cl concentrations in the Antarctic Dome Fuji ice core at quasi-annual and 4–5 years resolutions, respectively. Based on the combined 14C, 10Be, and 36Cl data, the 5480 BCE event was probably not caused by a solar proton event (SPE) or a gamma-ray event, because the 36Cl concentration did not significantly increase as expected in these events. The incremented 10Be data were enhanced similarly to those of recent grand solar minima, but more rapidly increased (over ∼10 years). These results suggest that an unusual grand solar minimum occurred around 5480 BCE, characterized by a rapidly decreasing solar activity.

DOI： 10.1029/2021JA029378

Web of Science

Scopus

The measurement of ion-induced cloud nucleation irradiated with a 180-MeV nitrogen ion and proton beams at HIMAC accelerator facility

Suzuki A., Itow Y., Sako T., Nakayama T., Masuda K., Miyake F., Matsumi Y., Miura K., Kusano K.

Proceedings of Science Vol. 358 2021.7

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Proceedings of Science

Ion-induced nucleation by cosmic rays influenced by solar modulation is of interest, and several studies with radioactive sources or accelerator beams have been performed. We focused on ionization with high-linear energy transfer (LET) particles, such as protons, neutrons, and ions, in secondary cosmic rays and the ion density of the secondary cosmic rays near the ground using the excel-based program for calculating atmospheric cosmic-ray spectrum (EXPACS). According to the calculation, not only muons but also protons and neutrons leave substantial traces of solar modulation at an altitude of 3 km from the ground. To verify the ion-induced nucleation by these secondary high-LET cosmic rays, a chamber experiment was conducted at the accelerator facility HIMAC. Using a chamber with a capacity of 75 L, experiments were conducted by irradiating protons and nitrogen ion beams with a constant energy of 180 MeV/u with varying intensity. The experimental results confirm that the ion density and aerosol density increased as the beam intensity increased. The aerosol density was found to be proportional to the ion density, but irrelevant to the ionization density. It was concluded that the ion-induced nucleation by high-LET secondary cosmic rays, such as protons and neutrons, provides no evidence of enhancement owing to ionization density and cannot account for the claimed variation of cloud formation due to the solar modulation.

Scopus

Cosmogenic Evidence for Past SEP Events

Miyake F.

Proceedings of Science Vol. 358 2021.7

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Proceedings of Science

Terrestrial cosmogenic nuclides (e.g., 14C, 10Be, and 36Cl) are primarily produced by galactic cosmic rays. However, a certain amount of these nuclides is also produced by solar energetic particles (SEPs) derived from sporadic solar events such as solar flares and coronal mass ejections. Cosmic ray increase events in AD 774/775, AD 993/994 (or AD 992/993), and ~BC 660 have been discovered using 14C data in tree rings (Miyake et al. 2012, 2013; Park et al. 2017). It is considered that the most plausible cause of these events was an extreme SEP events with very hard energy spectra based on 14C analyses of tree rings and 10Be and 36Cl analyses of ice cores (e.g., Mekhaldi et al. 2015; Miyake et al. 2015, 2019; Büntgen et al. 2018; O'Hare et al. 2019). These SEP events are estimated to be several dozens of times larger than the largest events seen in direct observations, and an event of that size might have a serious impact on modern society. Therefore, it is important to investigate the occurrence rate of past extreme events. In recent years, surveys of past SEP events have been actively conducted via cosmogenic nuclide measurements with high time resolution (~one-year resolution). Here the detected past SEP candidates and a further survey of similar events are reviewed.

Scopus

The measurement of ion-induced cloud nucleation irradiated with a 180-MeV nitrogen ion and proton beams at HIMAC accelerator facility

Suzuki A., Itow Y., Sako T., Nakayama T., Masuda K., Miyake F., Matsumi Y., Miura K., Kusano K.

Proceedings of Science Vol. 358 2021.7

Language：English Publishing type：Research paper (scientific journal) Publisher：Proceedings of Science

Scopus

Exploration of Carrington SEP(Solar Energetic Particle) Event with radiocarbon in tree-ring

Tada Yuma, Miyake Fusa, Kanzawa Kayo, Nakamura Toshio, Nakatuka Takeshi, Tokanai Fuyuki, Sakamoto Minoru, Hakozaki Makoto

JSAP Annual Meetings Extended Abstracts Vol. 2020.2 page： 356 - 356 2020.8

Findings from an in-Depth Annual Tree-Ring Radiocarbon Intercomparison Reviewed International coauthorship International journal Open Access

L. Wacker, E. M. Scott, A. Bayliss, D. Brown, E. Bard, S. Bollhalder, M. Friedrich, M. Capano, A. Cherkinsky, D. Chivall, B. J. Culleton, M. W. Dee, R. Friedrich, G. W.L. Hodgins, A. Hogg, D. J. Kennett, T. D.J. Knowles, M. Kuitems, T. E. Lange, F. Miyake, M. J. Nadeau, T. Nakamura, J. P. Naysmith, J. Olsen, T. Omori, F. Petchey, B. Philippsen, C. Bronk Ramsey, G. V.Ravi Prasad, M. Seiler, J. Southon, R. Staff, T. Tuna

Radiocarbon Vol. 62 ( 4 ) page： 873 - 882 2020.8

Language：English Publishing type：Research paper (scientific journal)

© 2020 Cambridge University Press. All rights reserved. The radiocarbon (C) calibration curve so far contains annually resolved data only for a short period of time. With accelerator mass spectrometry (AMS) matching the precision of decay counting, it is now possible to efficiently produce large datasets of annual resolution for calibration purposes using small amounts of wood. The radiocarbon intercomparison on single-year tree-ring samples presented here is the first to investigate specifically possible offsets between AMS laboratories at high precision. The results show that AMS laboratories are capable of measuring samples of Holocene age with an accuracy and precision that is comparable or even goes beyond what is possible with decay counting, even though they require a thousand times less wood. It also shows that not all AMS laboratories always produce results that are consistent with their stated uncertainties. The long-term benefits of studies of this kind are more accurate radiocarbon measurements with, in the future, better quantified uncertainties.

DOI： 10.1017/RDC.2020.49

Open Access

Web of Science

Scopus

775 and 994 14C events in the tree-rings of northern Japanese trees International journal

M. Hakozaki, F. Miyake, T. Nakamura

Proceedings of EA-AMS 8 & JAMS-22 page： 89 - 90 2020.6

Measurements of Radionuclides International journal

Wacker L, Baroni M, Mekhaldi F, Miyake F, Oinonen M

EXTREME SOLAR PARTICLE STORMS: THE HOSTILE SUN 2020

Further Search for Extreme Events International journal

Miyake F, Ebihara Y, Hayakawa H, Maehara H, Mitsuma Y, Usoskin I, Wang F, Willis D. M

EXTREME SOLAR PARTICLE STORMS: THE HOSTILE SUN 2020

Extreme Solar Particle Storms The hostile Sun Introduction International journal

Usoskin I, Miyake F

EXTREME SOLAR PARTICLE STORMS: THE HOSTILE SUN 2020

Characterization of the Measured Events International journal

Cliver E, Ebihara Y, Hayakawa H, Jull T, Mekhaldi F, Miyake F, Muscheler R

EXTREME SOLAR PARTICLE STORMS: THE HOSTILE SUN 2020

古木から読み解く過去の宇宙

三宅芙沙

日本歴史 Vol. 870号（11月号） page： 74 - 75 2020

Past cosmic-ray increase events detected from high-precision 14C data Invited Reviewed

Fusa Miyake

Hoshasen Vol. 45 ( 3 ) page： 144 - 149 2020

Radiocarbon Production Events and their Potential Relationship with the Schwabe Cycle Reviewed International journal Open Access

A. Scifo, M. Kuitems, A. Neocleous, B. J. S. Pope, D. Miles, E. Jansma, P. Doeve, A. M. Smith, F. Miyake, M. W. Dee

Scientific Reports Vol. 9 ( 1 ) page： 17056 2019.11

Language：English Publishing type：Research paper (scientific journal)

Extreme cosmic radiation events occurred in the years 774/5 and 993/4 CE, as revealed by anomalies in the concentration of radiocarbon in known-age tree-rings. Most hypotheses point towards intense solar storms as the cause for these events, although little direct experimental support for this claim has thus far come to light. In this study, we perform very high-precision accelerator mass spectrometry (AMS) measurements on dendrochronological tree-rings spanning the years of the events of interest, as well as the Carrington Event of 1859 CE, which is recognized as an extreme solar storm even though it did not generate an anomalous radiocarbon signature. Our data, comprising 169 new and previously published measurements, appear to delineate the modulation of radiocarbon production due to the Schwabe (11-year) solar cycle. Moreover, they suggest that all three events occurred around the maximum of the solar cycle, adding experimental support for a common solar origin.

DOI： 10.1038/s41598-019-53296-x

The Earliest Candidates of Auroral Observations in Assyrian Astrological Reports: Insights on Solar Activity around 660 BCE Reviewed International journal Open Access

H. Hayakawa, Y. Mitsuma, Y. Ebihara, F. Miyake

Astrophys. J. Lett. Vol. 884 ( 1 ) 2019.10

Language：English Publishing type：Research paper (scientific journal) Publisher：IOP PUBLISHING LTD

Auroral records found in historical archives and cosmogenic isotopes found in natural archives have served as sound proxies of coronal mass ejections and solar energetic particles (SEPs), respectively, for dates prior to the onset of telescopic sunspot observations in 1610. These space weather events constitute a significant threat to a modern civilization, because of its increasing dependency on an electronic infrastructure. Recent studies have identified multiple extreme space weather events derived from SEPs in natural archives, such as the event in 660 BCE. While the level of solar activity around 660 BCE is of great interest, this had not been within the coverage of the hitherto-known datable auroral records in historical documents that extend back to the 6th century BCE. Therefore, we have examined Assyrian astrological reports in the 8th and 7th centuries BCE, identified three observational reports of candidate aurorae, and dated these reports to approximately 680 BCE-650 BCE. The Assyrian cuneiform tablets let us extend the history of auroral records and solar activity by a century. These cuneiform reports are considered to be the earliest datable records of candidate aurorae and they support the concept of enhanced solar activity suggested by the cosmogenic isotopes from natural archives.

DOI： 10.3847/2041-8213/ab42e4

Web of Science

Scopus

Cosmogenic Evidence for Past SEP Events International journal

MIYAKE Fusa

Proc. 36th International Cosmic Ray Conference 2019.8

Annual variation of cosmic ray intensities for the past 3,000 years International journal

Proceedings of the 20th Japanese Symposium on Accelerator Mass Spectrometry ( 2018-002 ) page： 83 - 86 2019.2

Cosmogenic evidence for past SEP events International journal

Miyake F.

Proceedings of Science Vol. 358 2019

Language：English Publishing type：Research paper (scientific journal) Publisher：Proceedings of Science

Scopus

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Papers - MIYAKE Fusa