Hiroko Miyahara

Datos Biográficos

ID4129629
NOMBREHiroko Miyahara
NOMBRESHiroko
APELLIDOMiyahara
FIRMAMIYAHARA H
AFILIACIONESInstitute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8582, Japan
ORCID0000-0001-6787-443X
VERIFICADOSí
TOTAL DE OBRAS9
TOTAL DE CITAS12
TOTAL COMO AUTOR9
TOTAL COMO EDITOR0
PRIMER AÑO DE PUBLICACIÓN2004
AÑO MÁS RECIENTE DE PUBLICACIÓN2026
ÍNDICE H2

  • Radiocarbon changes in the XI century CE in annual tree rings

    Open AccessAndrzej Rakowski, Jacek Pawlyta et al.ARTICLERadiocarbon2026Referencias: 39

    This paper presents new radiocarbon ( 14 C) measurements from annual tree rings of English oak ( Quercus robur L.) from Kujawy, Poland, spanning 1042–1062 CE. The results confirm an increase in Δ 14 C values between 1053 and 1055 CE, within the Oort Minimum of solar activity, consistent with literature values (Brehm et al. 2021a; Eastoe et al. 2019; Terrasi et al. 2020). The data reveal a sustained increase in Δ 14 C values between 1053 and 1055 …

  • Radiocarbon Concentration in Sub-Annual Tree Rings From Poland Around 660 Bce

    Open AccessAndrzej Rakowski, Jacek Pawlyta et al.ARTICLERadiocarbon2024Citada por: 4Referencias: 46

    The article presents results of measurements of radiocarbon ( 14 C) concentration in sub-annual dendrochronologically dated tree rings of English oak ( Quercus robur L.) from Grabie village near Kraków (southern Poland). Samples of early wood (EW) and late wood (LW) spanning the years 664–658 BCE. α-cellulose was extracted from each sample and their radiocarbon content was measured at the ATOMKI laboratory in Debrecen, Hungary. The EW and LW data…

  • A Study of Variation of the 11-yr Solar Cycle before the onset of the Spoerer Minimum based on Annually measured 14 C Content in tree Rings

    Open AccessToru Moriya, Hiroko Miyahara et al.ARTICLERadiocarbon2019Citada por: 2Referencias: 19

    Proxy-based observations of solar activity in the past have revealed long-term variations, such as the Gleissberg cycle (~88 yr), de Vries cycle (~200 yr), and the Hallstatt cycle (~2000 yr). Such long-term variations of solar activity sometimes cause the disappearance of sunspots for several decades. Currently, solar activity is becoming weaker, and there is a possibility that another long-term sunspot minimum could occur. However, the detailed …

  • Hydroclimate reconstruction in central Japan over the past four centuries from tree-ring cellulose δ 18 O

    Open AccessWataru Sakashita, Hiroko Miyahara et al.ARTICLEQuaternary International2017

  • Relationship between early summer precipitation in Japan and the El Niño-Southern and Pacific Decadal Oscillations over the past 400 years

    Open AccessWataru Sakashita, Yūsuke Yokoyama et al.ARTICLEQuaternary International2016

  • Present Status of YU-AMS System

    Open AccessFuyuki Tokanai, Kazuhiro Kato et al.ARTICLERadiocarbon2013Citada por: 2Referencias: 14

    A new compact accelerator mass spectrometry (AMS) system has been installed in the Kaminoyama Research Institute at Yamagata University (YU). The AMS system is based on a 0.5MV Pelletron accelerator developed by the National Electrostatics Corporation. An automated acid-alkali-acid (AAA) treatment system and an automated graphitization line were also installed in the same facility for sample preparation. Performance tests of the YU-AMS system wer…

  • Latest 14 C Concentrations of Plant Leaves at High Altitudes in the Northern and Southern Hemispheres

    Open AccessHirohisa Sakurai, Fuyuki Tokanai et al.ARTICLERadiocarbon2013Citada por: 2Referencias: 10

    The radiocarbon concentrations in plant leaves from different altitudes at 3 sampling locations were measured with the new compact accelerator mass spectrometer (AMS) at Yamagata University to investigate air mixing on a global scale. The sampling locations are Yamagata in the mid-latitudes of the Northern Hemisphere (NH), Kenya in the equatorial region (EQ), and Chacaltaya in the Southern Hemisphere (SH). The 14 C concentrations of the plant lea…

  • Years of Cosmic Radiation and Solar Activity From Ice Cores and Tree Rings

    Open AccessFriedhelm Steinhilber, Jose A Abreu et al.ARTICLEProceedings of the National…2012

    Understanding the temporal variation of cosmic radiation and solar activity during the Holocene is essential for studies of the solar-terrestrial relationship. Cosmic-ray produced radionuclides, such as 10 Be and 14 C which are stored in polar ice cores and tree rings, offer the unique opportunity to reconstruct the history of cosmic radiation and solar activity over many millennia. Although records from different archives basically agree, they a…

  • Variation of the Radiocarbon Content in Tree Rings During the Spoerer Minimum

    Open AccessHiroko Miyahara, Kimiaki Masuda et al.ARTICLERadiocarbon2004Citada por: 2Referencias: 6

    This paper presents the variation of radiocarbon content in annual tree rings for the period AD 1413–1553, which includes the Spoerer Minimum period (AD 1415–1534). Since the variation of the production rate of 14 C is strongly related to solar activity, the variation of 14 C content in annual tree rings gives us information on the characteristics of variation of solar activity. We have studied solar activity during the grand solar minima, focusi…