Kimiaki Masuda
Biographic Data
| ID | 4129631 |
|---|---|
| NAME | Kimiaki Masuda |
| GIVEN NAMES | Kimiaki |
| FAMILY NAME | Masuda |
| SIGNATURE | MASUDA K |
| AFFILIATIONS | Nagoya University |
| VERIFIED | No |
| TOTAL WORKS | 12 |
| TOTAL CITATIONS | 58 |
| AUTHOR COUNT | 12 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1997 |
| LATEST PUBLICATION YEAR | 2018 |
| H-INDEX | 4 |
More Rapid 14 C Excursions in the Tree-Ring Record: A Record of Different Kind of Solar Activity at About 800 BC
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Verification of the Annual Dating of the 10th Century Baitoushan Volcano Eruption Based on an AD 774–775 Radiocarbon Spike
The so-called Millennium Eruption of Baitoushan Volcano is one of the largest of the Common Era but its date has been uncertain. Recently, Oppenheimer et al. (2017) reported the eruptive year as late AD 946 using a new method called carbon-14 spike matching. However, it is necessary to verify their result to confirm the eruptive year, since only one wood sample was used in their study. We verified the eruptive year by measuring 14 C contents in t…
Search for Annual 14 C Excursions in the Past
Two radiocarbon excursions (AD 774–775 and AD 993–994) occurred due to an increase of incoming cosmic rays on a short timescale. The most plausible cause of these events is considered to be extreme solar proton events (SPE). It is possible that there are other annual 14 C excursions in the past that have yet to be confirmed. In order to detect more of these events, we measured the 14 C contents in bristlecone pine tree-ring samples during the per…
High-precision age determination of Holocene samples by radiocarbon dating with accelerator mass spectrometry at Nagoya University
Verification of the Cosmic-Ray Event in AD 993–994 by Using a Japanese Hinoki Tree
A rapid yearly increase in the radiocarbon content has been detected for the period from AD 993 to 994. However, this event is supported by the 14 C measurements of only one cedar tree sample, and verification is necessary to confirm this event more reliably. For this purpose, this study measured the 14 C content in Japanese Hinoki tree rings corresponding to the period from AD 988 to 997 using the accelerator mass spectrometry system at Yamagata…
Measuring 14 C Concentration in Wine to Monitor Global Distribution of 14 C
Using liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS), radiocarbon concentrations were measured for wine from 8 wineries located in 7 countries in the Northern and Southern hemispheres. The 14 C concentrations of ethanol and residual materials in the wine were correlated (correlation coefficient 0.82). The δ 14 C measurements of wine samples from the mid-latitudes in the Northern Hemisphere were approximately 1l% lower…
Radiocarbon Ages of Annual Rings from Japanese Wood: Evident Age Offset Based on IntCal09
To investigate the radiocarbon concentration of atmospheric CO 2 over the past few millennia in Japan, we measured the 14 C age of annual rings from 3 Japanese trees with calendar dates ranging from ∼2000 yr old to present, and we compared the tree-ring 14 C age with the corresponding 14 C age from IntCal09. In some instances, the 14 C ages of the annual rings of Japanese trees are not consistent with the IntCal09 data sets. Often, the 14 C ages …
Latest 14 C Concentrations of Plant Leaves at High Altitudes in the Northern and Southern Hemispheres: Vertical Stability of Local Suess Effect
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…
A signature of cosmic-ray increase in ad 774–775 from tree rings in Japan
Variation of the Radiocarbon Content in Tree Rings During the Spoerer Minimum
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…
Measurement of Radiocarbon Content in Leaves from Some Japanese Sites
We have measured radiocarbon contents in leaves collected from 15 sites in Japan, including mountain areas and big city areas for last three years. Comparing the radiocarbon contents in various areas, high 14 C concentrations (80–100‰ as δ 14 C) are seen for the leaves from the mountain and country sites. On the contrary, low concentrations (5–40‰) were observed for the leaves from city region, especially near the road with heavy traffic. These r…
The New Nagoya Radiocarbon Laboratory
A liquid scintillation counting apparatus that enables highly accurate measurements of 14 C has been constructed at the Solar-Terrestrial Environment Laboratory, Nagoya University. The main aim of the project is high precision year-by-year measurements of the 14 C content in tree rings of an old cedar tree from Yaku Island, Japan. We present the results of 14 C measurements on tree rings from the Agematsu region for recent decades to confirm the …
More Rapid 14 C Excursions in the Tree-Ring Record: A Record of Different Kind of Solar Activity at About 800 BC
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Verification of the Cosmic-Ray Event in AD 993–994 by Using a Japanese Hinoki Tree
A rapid yearly increase in the radiocarbon content has been detected for the period from AD 993 to 994. However, this event is supported by the 14 C measurements of only one cedar tree sample, and verification is necessary to confirm this event more reliably. For this purpose, this study measured the 14 C content in Japanese Hinoki tree rings corresponding to the period from AD 988 to 997 using the accelerator mass spectrometry system at Yamagata…
Radiocarbon Ages of Annual Rings from Japanese Wood: Evident Age Offset Based on IntCal09
To investigate the radiocarbon concentration of atmospheric CO 2 over the past few millennia in Japan, we measured the 14 C age of annual rings from 3 Japanese trees with calendar dates ranging from ∼2000 yr old to present, and we compared the tree-ring 14 C age with the corresponding 14 C age from IntCal09. In some instances, the 14 C ages of the annual rings of Japanese trees are not consistent with the IntCal09 data sets. Often, the 14 C ages …
Verification of the Annual Dating of the 10th Century Baitoushan Volcano Eruption Based on an AD 774–775 Radiocarbon Spike
The so-called Millennium Eruption of Baitoushan Volcano is one of the largest of the Common Era but its date has been uncertain. Recently, Oppenheimer et al. (2017) reported the eruptive year as late AD 946 using a new method called carbon-14 spike matching. However, it is necessary to verify their result to confirm the eruptive year, since only one wood sample was used in their study. We verified the eruptive year by measuring 14 C contents in t…
Search for Annual 14 C Excursions in the Past
Two radiocarbon excursions (AD 774–775 and AD 993–994) occurred due to an increase of incoming cosmic rays on a short timescale. The most plausible cause of these events is considered to be extreme solar proton events (SPE). It is possible that there are other annual 14 C excursions in the past that have yet to be confirmed. In order to detect more of these events, we measured the 14 C contents in bristlecone pine tree-ring samples during the per…
Measurement of Radiocarbon Content in Leaves from Some Japanese Sites
We have measured radiocarbon contents in leaves collected from 15 sites in Japan, including mountain areas and big city areas for last three years. Comparing the radiocarbon contents in various areas, high 14 C concentrations (80–100‰ as δ 14 C) are seen for the leaves from the mountain and country sites. On the contrary, low concentrations (5–40‰) were observed for the leaves from city region, especially near the road with heavy traffic. These r…
Latest 14 C Concentrations of Plant Leaves at High Altitudes in the Northern and Southern Hemispheres: Vertical Stability of Local Suess Effect
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…
Variation of the Radiocarbon Content in Tree Rings During the Spoerer Minimum
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…
The New Nagoya Radiocarbon Laboratory
A liquid scintillation counting apparatus that enables highly accurate measurements of 14 C has been constructed at the Solar-Terrestrial Environment Laboratory, Nagoya University. The main aim of the project is high precision year-by-year measurements of the 14 C content in tree rings of an old cedar tree from Yaku Island, Japan. We present the results of 14 C measurements on tree rings from the Agematsu region for recent decades to confirm the …
The New Nagoya Radiocarbon Laboratory
A liquid scintillation counting apparatus that enables highly accurate measurements of 14 C has been constructed at the Solar-Terrestrial Environment Laboratory, Nagoya University. The main aim of the project is high precision year-by-year measurements of the 14 C content in tree rings of an old cedar tree from Yaku Island, Japan. We present the results of 14 C measurements on tree rings from the Agematsu region for recent decades to confirm the …
Measurement of Radiocarbon Content in Leaves from Some Japanese Sites
We have measured radiocarbon contents in leaves collected from 15 sites in Japan, including mountain areas and big city areas for last three years. Comparing the radiocarbon contents in various areas, high 14 C concentrations (80–100‰ as δ 14 C) are seen for the leaves from the mountain and country sites. On the contrary, low concentrations (5–40‰) were observed for the leaves from city region, especially near the road with heavy traffic. These r…
Variation of the Radiocarbon Content in Tree Rings During the Spoerer Minimum
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…
A signature of cosmic-ray increase in ad 774–775 from tree rings in Japan
Measuring 14 C Concentration in Wine to Monitor Global Distribution of 14 C
Using liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS), radiocarbon concentrations were measured for wine from 8 wineries located in 7 countries in the Northern and Southern hemispheres. The 14 C concentrations of ethanol and residual materials in the wine were correlated (correlation coefficient 0.82). The δ 14 C measurements of wine samples from the mid-latitudes in the Northern Hemisphere were approximately 1l% lower…
Radiocarbon Ages of Annual Rings from Japanese Wood: Evident Age Offset Based on IntCal09
To investigate the radiocarbon concentration of atmospheric CO 2 over the past few millennia in Japan, we measured the 14 C age of annual rings from 3 Japanese trees with calendar dates ranging from ∼2000 yr old to present, and we compared the tree-ring 14 C age with the corresponding 14 C age from IntCal09. In some instances, the 14 C ages of the annual rings of Japanese trees are not consistent with the IntCal09 data sets. Often, the 14 C ages …
Latest 14 C Concentrations of Plant Leaves at High Altitudes in the Northern and Southern Hemispheres: Vertical Stability of Local Suess Effect
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…
Verification of the Cosmic-Ray Event in AD 993–994 by Using a Japanese Hinoki Tree
A rapid yearly increase in the radiocarbon content has been detected for the period from AD 993 to 994. However, this event is supported by the 14 C measurements of only one cedar tree sample, and verification is necessary to confirm this event more reliably. For this purpose, this study measured the 14 C content in Japanese Hinoki tree rings corresponding to the period from AD 988 to 997 using the accelerator mass spectrometry system at Yamagata…
High-precision age determination of Holocene samples by radiocarbon dating with accelerator mass spectrometry at Nagoya University
Search for Annual 14 C Excursions in the Past
Two radiocarbon excursions (AD 774–775 and AD 993–994) occurred due to an increase of incoming cosmic rays on a short timescale. The most plausible cause of these events is considered to be extreme solar proton events (SPE). It is possible that there are other annual 14 C excursions in the past that have yet to be confirmed. In order to detect more of these events, we measured the 14 C contents in bristlecone pine tree-ring samples during the per…
More Rapid 14 C Excursions in the Tree-Ring Record: A Record of Different Kind of Solar Activity at About 800 BC
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Verification of the Annual Dating of the 10th Century Baitoushan Volcano Eruption Based on an AD 774–775 Radiocarbon Spike
The so-called Millennium Eruption of Baitoushan Volcano is one of the largest of the Common Era but its date has been uncertain. Recently, Oppenheimer et al. (2017) reported the eruptive year as late AD 946 using a new method called carbon-14 spike matching. However, it is necessary to verify their result to confirm the eruptive year, since only one wood sample was used in their study. We verified the eruptive year by measuring 14 C contents in t…
Geology (11 works) · Radiocarbon dating (11 works) · Geology and Paleoclimatology Research (10 works) · Archaeology and ancient environmental studies (8 works) · Geography (8 works) · Paleontology (8 works) · Physical geography (7 works) · Environmental Science (6 works) · Physics (6 works) · Archaeology (5 works)