The Tibetan Plateau plays an important role in the global carbon cycle. Despite its significance, the mechanisms, sources and fluxes of CO2 emissions from this region remain poorly understood. This study employs radiocarbon to trace the origins of CO2 released in the southern Tibetan Plateau. Combining 14C and other geochemical proxies (chemical compositions, 3He/4He, δ13C, etc.) from soil...
Advanced 14C dating on organic carbon with distinct bond strengths for terrestrial carbon cycling dynamics
Hong Wang1, Xiaofei Gao1, Peng Cheng2, Yi Yang1, Jia Cao1, Dongxue Li3, Peixian Shu2, Guodong Ming4, Yingna Liu1, Keli Zhang1, Baoshan Cui3, Yongming Han2, Xuefeng Lu2, Hua Du2, Feng Xian2, Sanyuan Zhu5, Yanmin Sun5, Tianhe Liu1, Lin liu1, Xiaolei Zhao1, Weijian Zhou2, Zhisheng An2...
The integration of a unique low-energy isobar suppression unit, the Anion Laser Isobar Separator (ALIS), marks a significant extension to the CologneAMS infrastructure. After the successful test of the advanced gas-filled radio frequency quadrupole (RFQ) ion cooler at the Vienna test bench, we present insights from first benchmark tests conducted at ALIS.
ALIS consists of three major...
Classical AMS measurements of $^{36}$Cl require high ion energies to enable isobar separation of $^{36}$S by nuclear separation techniques exploiting the different stopping power of S vs. Cl. The 6 MV Tandem accelerator at ETH Zurich was one of the first AMS systems being able to measure $^{36}$Cl already several decades ago [Synal et al. NIM B 29 (1987) 146] and has been heavily used for...
The need for alternative sources of fuel has motivated the search for production routes based on renewable materials that may equal the fossil options in efficiency and which are economically viable. For the fuel industry to adapt to this reality, it is necessary to size up the investment in new production plants and in the development of new technologies. Regulatory bodies are supposed to...
Volcanic activities are known to release a substantial amount of deep carbon to the Earth’s surface, thereby influencing the global carbon cycle on geological timescales. Volcanic activities release CO₂ to the atmosphere not only from the crater, but also from the flank and base of the volcanoes in the form of soil emissions, hot springs, vents, and deep carbon in dissolved state. Carbon...
Radiocarbon has presented its importance in versatile applications, ranging from dating ancient (in e.g. Quaternary study and archaeology) or modern (in e.g. forensic science) samples, tracing metabolic pathways in human bodies, to determination of bio-/fossil- components (in fuel, fabric, or even emissions of green-house gases and particulate pollution) for environmental considerations. The...
The compact 0.3MV MILEA AMS facility was developed at ETH Zurich in collaboration with Ionplus AG, Switzerland, as an optimized low energy AMS system for the analysis of a series of long-lived radioisotopes such as $^{10}$Be, $^{14}$C, $^{26}$Al, $^{41}$Ca, $^{129}$I and actinides. The MILEA facility is equipped with a vacuum insulated accelerator that is powered by a commercial solid state...
As a large carbon emitter, how much of the increased atmospheric CO2 derived from fossil fuel emissions is not only an important scientific question, but also important to assess the current policies of carbon peak and carbon neutrality in China. Because of the complete depletion in fossil fuels, radiocarbon (14C) is regarded as an independent and objective tool to evaluate fossil fuel CO2...
The 20 AMS 14C dates on a 96-cm long core (22-Al-02A) from Kolyvanskoe Lake in the Altai Krai, exhibit nuclear bomb 14C influence in the upper 13 cm part. However, the bomb 14C curve may have changed its shape owing to old carbon influence (OCI). An age-depth model (with selected 14C ages having less OCI) has been established for the past 3000 years by using the Bayesian statistical Bacon...
Radiocarbon measurement technology has significant applications in archaeology, earth science, environmental science, biomedicine and so on, especially in radioactive dating, climate change, nuclear analysis, pharmacokinetics. The traditional 14C accelerator mass spectrometer (14C-AMS) based on tandem is much expensive and complex to maintain and operation. It is urgent to develop a new type...
Analysis of 14C radioactivity in seawater of Beibu Gulf, Guangxi, China, using GXNU-AMS
After the Fukushima nuclear accident in Japan, the safety management of nuclear power has been emphasized by various countries, while the radioactivity levels in the environment surrounding nuclear power plants have also received public attention. Studies have shown that the persistence of nuclear...
$^{53}$Mn is a rare, radioactive isotope with a half-life of 3.74 million years which has astrophysical applications as an early solar system chronometer and as a test of nucleosynthesis models of supernovae and asymptotic giant branch (AGB) stars. In addition, $^{53}$Mn has geological applications in determining the exposure and burial age of ferromanganese minerals. To fully exploit the...
Since few years the Centre of Applied Physics Dating and Diagnostics (CEDAD) at the University of Salento is collaborating with the Committee on Missing Persons in Cyprus (CMP) for the analysis of the human skeleton remains of around two thousand persons who went missing during the inter-communal fighting of 1963-64 and the events of 1974.
The aim of the CMP, supported by the United Nations,...
The negative ion source most commonly used in AMS systems is the cesium sputter type. Cesium is hazardous, making its handling not easy. Recently, the spread of compact AMS systems with acceleration voltages of 500 kV or less has been progressing. For the widespread adoption of AMS systems, it is desirable for the ion source to not only be highly efficient but also cesium-free from the...
Urban areas are responsible for the vast majority of fossil fuel carbon dioxide emissions, thus mitigation actions are often taken at the city level. Detailed information about urban emissions and offsetting potential is needed to guide mitigation actions and to evaluate the efficacy of these actions. CarbonWatch-Urban is a multi-tiered approach to provide fine-scale carbon dioxide emissions...
In the CRC1211 project "Evolution at the Dry Limit", precise dating analysis of soil samples from the Atacama Desert is essential. These soil samples result in ultra small CO$_2$ samples and have a carbon content of 2-20μg. At CologneAMS ultra-small samples are measured as CO$_2$ with, an elemental analyzer (EA), an isotope ratio mass spectrometer (IRMS) and the 6MV AMS system, by the use of a...
The μGRAPHILINE, introduced in 2024, offers a new, fully automatic graphitization process, enabling rapid, reliable, and precise graphitization using the zinc reduction method for radiocarbon dating. While the majority of radiocarbon samples include bone, wood, charcoal, plant remains, carbonates, and sediments (Dee et al. 2020), there are niche areas of other samples that can be dated with...
Investigating the dissolved inorganic carbon (DIC) processes and associated chemical and isotopic (13C and 14C) evolutions is critical for deciphering its implications on climate change and groundwater quality. Growing number of 13C and 14C measurements of DIC in recent years,however, it is still unclear about the DIC evolution. In this study, we synthesize and deduce the isotopic...
Radiocarbon (14C) composition of dissolved organic carbon (DOC) provides critical constraints on its sources, transformation and cycles. UV-irradiation is considered as an effective approach to oxidize the fresh/salty DOC to CO2 of samples with typical low concentration for high precision radiocarbon measurements. However, the challenge of this method is the complete oxidation of sufficient...
81Kr is a cosmogenic isotope with a half-life of 229 ka. Due to its chemical inertness, it has a uniform distribution in the atmosphere and a simple transport behavior in the environment, avoiding some complexities in 14C dating. Therefore, 81Kr is an ideal tracer in the earth sciences.
Limited by the precision of 81Kr analysis, there is a dating gap between 14C and 81Kr. Recently, we have...
Advancements in high-precision AMS radiocarbon ($^{14}$C) measurements coupled with sophisticated statistical techniques offer a powerful approach to uncovering and utilizing annual features in the $^{14}$C record. In recent years, signatures of rapid increases in cosmogenic $^{14}$C have been successfully used as tools for achieving exact-year dating, with the aid of Classical statistical...
The most common ion source of AMS instruments, the cesium sputter source (Middleton 1983), demands a substantial share of the regular maintenance work and causes a considerable number of operation interruptions. One reason is the difficulty of obtaining meaningful diagnostic measurements under the rough conditions inside. In addition to the high temperature and the strong electric fields, the...
Graphite target preparation is one of the key steps in accelerator mass spectrometry (AMS) radiocarbon chronology measurement, so it is crucial to make the graphitisation process simple and efficient. In traditional methods, desulphurisation of samples containing sulphur is essential, as sulphur can affect the yield of graphitisation, and usually requires the addition of silver to form Ag2S to...
Plutonium (Pu) is recognized as an essential environmental indicator isotope. The purpose of this investigation is to devise a protocol for extracting plutonium from soil samples, aimed at Accelerator Mass Spectrometry (AMS) analysis. The procedure initiates with the purification and ashing of samples, followed by the integration of the standard reference material 242Pu before proceeding to...
The most powerful anthropogenically influenced greenhouse gas after carbon dioxide is methane. Its atmospheric mixing ratio is much lower than of CO2, but the global warming potential of CH4 is more than eighty times higher, on a 20-year timescale (IPCC, 2021). The atmospheric amount of CH4 has been growing rapidly since 2007, and the reasons are unclear. Several types of sources can...
In this paper we apply cosmogenic nuclide dating to the selected key archaeological sites in the western Mediterranean region (southern Spain and Morocco), to provide better chronological constrains to sites where previous geochronological data were scarce, scattered or unresolved. Our knowledge on the early hominin dispersal out of Africa, e.g., timing, causes, pathways, remain incomplete....
The solar neighborhood lies within the Local Bubble, a low-density region of space formed by stellar explosions [1]. The Local Interstellar Cloud (LIC) with the solar system inside is embedded in this cavity. Assuming the LIC contains remnants from supernovae events, the solar system may accumulate traces of long-lived supernova-produced radionuclides as it traverses the LIC. The radionuclide...
The rare radioisotope Sr-90 is one of the most important products of thermal neutron fission. On one hand, the Sr-90 yield from fission is relatively large;on the other hand, 90Sr is known for its bone-seeking radiotoxicity and the risk of causing bone cancer. Currently, researches related to 90Sr are facing the challenge of measuring the concentration of Sr-90 environmental samples, which...
Surface exposure dating, which calculates the exposure age of rocks based on the accumulation of in-situ cosmogenic nuclides on the ground surface, is a very useful technique for directly dating the age of exposed rocks. Surface exposure dating has many advantages, but the required high-precision measurement is not easy. This is mainly due to the extremely low abundance of cosmogenic nuclides....
In order to better characterize carbonaceous components in atmospheric aerosols and to assess the contributions of biomass sources in the carbonaceous aerosols in the regions where heavily influenced by field burning of agricultural wastes, we collected carbonaceous aerosols at the summit of Mt. Tai (1534 m above sea level) on a daytime and nighttime basis during a summertime campaign...
Cooling water is an essential part of the infrastructure of all but the smallest AMS instruments, and of particle accelerators in general. While facilities situated on larger scientific campuses often can rely on good quality water from a central supply, many instruments, including VERA at the University of Vienna, are situated on sites where a stand-alone provision is necessary. Because it is...
The positive ion source mass spectrometry is currently undergoing extensive research and development, being regarded as a more compact and cost-effective alternative to conventional tandem accelerator mass spectrometers. However, its elimination of the accelerator design presents challenges in overcoming the instability of low-energy carbon ion beams extracted by the Electron Cyclotron...
In 2018, an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) Accelerator Mass Spectrometer (AMS) was installed at the Laboratory of AMS Dating and the Environment, Nanjing University (NJU-AMS Laboratory), China. The NJU-AMS Laboratory is largely devoted to research on radiocarbon dating and 14C analysis in fields of earth, environmental and archaeological sciences. The laboratory has...
In the context of today's global warming, China has proposed the carbon emission reduction target of carbon peaking and carbon neutrality, while the increase in atmospheric carbon dioxide concentration is mainly caused by man-made fossil fuel emissions. Radiocarbon isotope (14C) is the most effective tracers of fossil fuel CO2 (CO2ff). In this study, 5-liter air bags and PQ200 instrument were...
Cl is a ubiquitous element in the environment. 36Cl ,half-life is 3.01x105a. The dating range can be up to 3.01x106a (10 times half-life), which covers the whole Quaternary period, has a unique advantage for the determination of Quaternary stratigraphy and Quaternary age. In recent years, with the continuous development of gas pedal mass spectrometry (AMS) technology, 36Cl has been measured...
A two-year (March 2021 to February 2023) continuous atmospheric CO2 and a one-year regular atmospheric 14CO2 measurement records were measured at the northern foot of the Qinling Mountains in Xi’an, China, aiming to study the temporal characteristics of atmospheric CO2 and the contributions from the sources of fossil fuel CO2 (CO2ff) and biological CO2 (CO2bio) fluxes. The two-year mean CO2...
Using helium as the stripping medium has become a dominant trend in 14C-AMS miniaturization. In order to explore how to utilize lower-energy beam for 14C analysis, more experimental data on low-energy C-He collisions are needed. In this work, the charge state yield versus target thickness after C- and helium collisions at 70-220 keV was investigated using the GXNU-AMS system, and the charge...
This report presents the radiocarbon dating results obtained for these Egyptian materials from the Kyoto University Museum, including Coptic textiles, mummy cloth and sandals. It also reports on the material database, the Kyoto University Research Information Repository, which includes radiocarbon dates and material analyses.
The Coptic Textile Collection of Egyptian Archaeological Materials...
The understanding of the formation of the elements has been an intriguing topic within the last decades. It is now proven that the heaviest naturally occurring elements, the actinides, are produced in the astrophysical r-process. However, the exact site of this process is still under debate. Recently, the amount of interstellar $^{244}$Pu (T$_{1/2}$ = 81.3 Myr) in various geological archives...
The Qinghai-Tibet Plateau is simultaneously influenced by the westerlies and the Asian monsoon, and the variations in monsoon moisture have significant impacts on the entire Qinghai-Tibet Plateau and Asian climate system. Among the interesting tracers of atmospheric circulation, the Be-10 isotope deposited in soils can be a potential one. The dominant atmospheric production, relatively long...
Wetlands are the largest carbon storage in the tundra zone of the Tibetan Plateau (amsl >4500 m), and the stored carbon is highly vulnerable to global warming. We selected two major wetland types in northern Tibet, lacustrine wetland (NC) and intermountain wetlands (NB), and took one soil profile each for soil organic carbon (SOC) content and carbon isotopes (δ13C & 14C) analysis. The results...
Abstract: To overcome the disadvantages of manual purification system during AMS-14C measurement, including inefficiency, unstable quality of graphite, and interference from modern carbon. CAGS-IHEG (Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences) introduced AGE-3 to improve the performance of small carbon graphite, leading to the rapid production...
Competitive AMS measurements of $^{26}$Al are possible at low ion energies. Selecting Al$^-$ as a negative ion for the tandem accelerator has the benefit of the complete suppression of the interfering isobar $^{26}$Mg. However, because of the notoriously low yield of Al$^-$ from a Cs sputter ion source, we have to pull out all the stops to improve the overall efficiency, in particular the...
The age of a small plant leaf frozen in ground ice at a depth of 8.3 meters in a borehole on the summit area of Mt. Goshiki in the Daisetsu Mountains, Hokkaido, Japan, was determined using radiocarbon dating. The calibrated age of the leaf (using OxCal v. 4.4.4) was 288±26 (40.0%) or 182±39 (48.2%) calendar years BP, placing it within the last Little Ice Age in Japan. This age indicates the...
Dissolved organic carbon (DOC) is a major, yet little understood component of the global carbon cycle. Although radiocarbon analysis of DOC provides valuable information on the origin and age of this pool, the number of measurements, particularly in marine systems, is limited by the complexity and low efficiency of existing methods. These methods generally use UV irradiation to oxidize the...
Oil sands (also tar sands) are a type of unconventional petroleum deposit from which bitumen is mined by surface mining or in-situ extraction to produce heavy oil. A globally significant soil sand region (producing 3.3 M barrels per day in 2022), is located in the Athabasca River basin of Alberta, Canada. The environmental impacts of oil sand mining, specifically air pollution, are not well...
Polycyclic aromatic hydrocarbons (PAHs) form one of the most important classes of persistent pollutants (Blumer 1976). Some PAHs are carcinogenic and mutagenic. Owing to their adverse effect on human/ecological health and widespread distribution around in the environment, identification of the sources of PAHs is of special concern (Pedersen et al. 2004). Thus, elucidating and evaluating the...
Uranium-236 serves as a widely utilized analytical tool for detecting environmental radioactive contamination and tracking natural processes. Given the low concentration of 236U in environmental samples, Accelerator Mass Spectrometry (AMS) emerges as a highly sensitive mass spectrometry method. Based on the AMS system at Guangxi Normal University (GXNU-AMS), we have developed and evaluated a...
The measurement of tritium by accelerator mass spectrometry (AMS) is a precise technique for determining tritium content. This technology is characterized by small sampling, high accuracy, and selectivity, making it a favorable method for measuring tritium in solids. In the process of measuring tritium by AMS, it is necessary to prepare the tritium-containing sample into the chemical form of...
Located within the Bataan volcanic arc of the Philippines is the potentially active Natib Volcano, situated on the western flank of Luzon Island near a decommissioned Bataan nuclear power plant (BNPP). As the Philippine government explores nuclear power as part of its energy mix, attention has shifted towards repurposing the former BNPP. However, despite its classification as potentially...
We applied the high temperature pyrolysis-combustion technique to 2 last glacial loess-paleosol sequences in the Chinese Loess Plateau (CLP) to partition the total soil organic carbon (SOC) into pyrolysis labile-recalcitrant and pyrolysis inert SOC fractions for accelerator mass spectrometry radiocarbon (AMS 14C) dating analysis to explore which SOC fraction yields more reliable AMS 14C...
Groundwater, the world's critical freshwater resource, is currently facing significant challenges from overexploitation and depletion, particularly on small islands such as Tongatapu in the Kingdom of Tonga. This study aimed to analyze the groundwater system of the island by integrating radiocarbon dating and water quality analysis. Groundwater samples were collected from coastal areas and...
Atmospheric nuclear weapons tests caused a dramatic increase of atmospheric 14CO2 with a peak around 1964, thereafter, bomb 14C became a powerful tool for dating recent carbonaceous material. There are lots of observational atmospheric 14CO2 records and reconstructed 14CO2 records based on annual tree rings covered bomb peak in the world, and they were compiled by Hua et al. in 2022. In China,...
129I is a long-lived nuclide with very low nature level, but the presence of 129I in the environment has changed significantly since the beginning of the nuclear era. Accelerator mass spectrometer (AMS) is the most sensitive method for 129I measurement, which is widely used in environmental monitoring, geological evolution dating, nuclear activities tracking and other fields. For further...
The 10Be record from the Northern Greenland NEEM ice core has been found to significantly correlate with the mid-latitude tropopause pressure on both seasonal and annual scales, highlighting the potential of applying ice core 10Be records to study the past stratosphere-troposphere exchange at mid-latitudes. However, a comprehensive study is required to determine if this relationship holds for...
Advances in Accelerator Mass Spectrometry (AMS) have made palaeoclimate reconstructions using meteoric cosmogenic nuclides available for a wide range of environments, including ocean, lake and ice cores (Raisbeck et al., 2007; Yokoyama et al., 2016; Behrens et al., 2022). Here, we report a Be-10 record for the past 45,000 years using sediments from Lake Biwa, the largest lake in Japan. The...
Introduction: Cl is a volatile element and can be lost during formation and evolution of planetary bodies, which can lead to fractionation of its two stable isotopes, 35Cl and 37Cl. Stable Cl isotope variations (reported as δ37Cl, in parts per thousand (‰), relative to standard mean ocean chloride (SMOC) [1]) have been measured in many lunar samples and have produced a wide range from -4‰ to...
The extractions of beryllium and aluminum samples by ion exchange resins prior AMS, depend heavily on the quality of quartz purity. However, even with meticulous purification, objectives to guarantee sufficient AMS current are not always achieved.
Using a well-known natural sample that had already been studied and purified, quantitative multi-elements (B, Be, Al, Ti, Ca, Na, K, Mg, Fe)...
The correction of " Reservoir Effect" in lake sediments is a particularly challenging issue in radiocarbon chronology. The controlling factors of Reservoir Effect and how to correct for it remain unclear. A research team systematically reviewed the past 20 years of lake studies in different climatic regions of China, and systematically investigated the 14C ages and correction methods used in...
Uranium mining and milling activities contribute to the release of natural uranium and its decay products into the environment. This may lead to potential radiological risks. While U-238 and its decay products are routinely monitored, the behaviour of the U-235 decay products is either not considered, or only estimated based on the U-238 decay chain in radiological assessments [1].
Pa-231 is...
In situ radiocarbon（14C）is produced within minerals at the earth’s surface by a number of spallation reactions. Due to its relatively short half-life of 5730 years, it serves as a unique cosmogenic nuclide tool for the measurement of measuring rapid erosion rates (>10–3 cm yr–1) and events occurring over the past 25,000 years. At Xi'an AMS Center, we have developed and constructed a new vacuum...
The Tibetan Plateau and its surrounding mountains (TPSM) has experienced glacier expansion during the Global Last Glacial Maximum and punctuated retreat during the following deglaciation. Preserved moraines provide a reliable record for glacier extent and their terrestrial cosmogenic exposure dating marks the transition of glacial advance or stasis to one of recession. As a wide geographic...
The purpose of this study is to establish a method for extracting charcoal from inside pottery and measuring its radiocarbon date. We proposed a new method that uses X-ray equipment to search for carbonised grains embedded within earthenware and directly date these grains in relation to grain cultivation in the Japanese archipelago [1]. This method allows us to obtain data on the introduction...
The development of the AMS 14C dating preparation laboratory has been completed in the Beijing Normal University (BNU). There are 2 lines of home-made CO2 generation vacuum systems and 4 lines of home-made graphitization vacuum systems. For CO2 generation, a pyrolysis-combustion vacuum system with an infrared gas analyzer, ultrapure O2 and Ar gas supply systems, a manometer with a pressure...
In this paper we revisit cosmogenic nuclide analysis from multilevel karst system in Atapuerca mountain range to discuss difficulty and complexity in interpretating cosmogenic data not only for chronology but also for sediment dynamics, i.e., provenance, transport pathway and depositional processes. Atapuerca is situated in the western end of Europe, and is among the key sites in the study of...
Understanding the sources and fluxes of dissolved inorganic carbon (DIC) in karst reservoirs is essential for regional carbon cycling studies, particularly concerning the "karst effect". This study utilized dual carbon isotopes (δ13CDIC and Δ14CDIC) to estimate the contribution rates and input fluxes of DIC from various sources in the Aha Reservoir (AHR), located in southwestern China. Our...
Atmospheric aerosols have serious impacts on the Earth’s climate system directly by scattering and absorbing solar radiation and indirectly by acting as cloud condensation nuclei. They also cause adverse effects on human health and play an important role in atmospheric chemistry. Although carbonaceous aerosols that represent a large fraction of fine aerosol mass have been extensively studied,...
The atmospheric concentration of carbon dioxide (CO$_{2}$) has been increasing steadily since industrialization. Emission of $^{14}$C-free CO$_{2}$ from the combustion of fossil fuels, such as coal, oil or gas, reduces the $^{14}$CO$_{2}$ to $^{12}$CO$_{2}$ ratio in the atmosphere. When the background $^{14}$CO$_{2}$ level is known, the local surplus of fossil CO$_{2}$ can be calculated using...
Suppression of isobars for AMS profits from studying element selective interactions of slow ions with photons or in collisions with other atoms. Negative ions extracted from an ion source can be slowed down to near-thermal energies in an ion cooler consisting of a buffer gas filled radio-frequency quadrupole. The slow ions collide with the buffer gas and can be overlapped with a laser beam....
Monitoring the fluctuations of radiocarbon in environmental samples (air, biological, groundwater, etc.) around nuclear facilities is a commonly used tool to assess the safe operation of the facility. Measurements of radiocarbon in environmental monitoring programs around the nuclear facility are primarily performed using liquid scintillation counters, which are known to be capable of...
Beloe Lake (51°17’40” N, 82°38’50” E, 530 m a.s.l.) is a foothill lake in the northwestern Altai of Russia. Twenty-five AMS 14C dates on sedimentary TOC and plant remaining samples were obtained from a 193-cm long core to construct the chronology of the lake sediment sequence. Additionally, 210Pb and 137Cs dating were applied to the uppermost 20 cm sediments of the core to complement the...
Since the acceptance of the 5MV AMS ASTER (CEREGE, Aix en Provence), the national laboratory LN2C is routinely measuring 10Be and 26Al for the scientific community. Previously based on a solvent extraction using EDTA and CCl4, we moved in 2008 due to the end of CCl4 production and to change for a safer chemistry, to a separation by ion exchange chromatography using anionic and cationic resins....
Iodine, as an essential biophilic element, is widely present in living organisms and crucial for human life activities. Among iodine isotopes, only iodine-127 is a stable nucleus, while iodine-129 has the longest half-life (1570 million years). Therefore, it is particularly important to isolate iodine from soil samples and utilize AMS to measure the ratio of iodine-129 to iodine-127 for...
The Xi'an AMS Center is equipped with a 3 MV accelerator mass spectrometer for multi-nuclides measurements, which provides a background of 10Be/9Be ratio up to 1.56×10-16, giving us favorable conditions to carry out environmental tracing study by using Chinese loess 10Be. Chinese loess-paleosol sequences are considered as one of three pillars for the global change research, along with marine...
Half-lives ought to be accurate, and preferably precise as well. In the recently published review on half-lives of long-lived radionuclides (Heinitz et al., 2022), several cases were mentioned where multiple half-life measurements on a specific radionuclide were incompatible with each other within the reported uncertainties. We call these “unsettled” half-lives. There are also cases where only...
The research on the Origin and Development of Chinese Civilization is a hot topic and involving many complex questions, such as the elements, process and paths of civilization. To establish the precision chronological frame is one of the most important aspects related to Chinese Civilization. The major scientific research project about Chinses civilization supported by the state that combines...
At the Centro Nacional de Aceleradores (CNA, Seville, Spain), research efforts are being devoted to exploring the limits of the 1 MV AMS system to analyse several radioisotopes present in nuclear waste that pose serious analytical challenges to radiometric techniques. The focus has been placed on 41Ca, 36Cl, and actinides radionuclides (239,240,241Pu, 236,238U, 237Np, 241,243Am and...
From the second millennium BC, two great cultures formed, traded and fought across Eurasia – one based on horses and herding that stretched from Mongolia to the European steppe, and the other, to the south that consisted of established and newly formed states from the Middle East to the Chinese Central Plains.
Horsepower: interactions between China, Mongolia and the steppe 2000–0 BC...
The astrophysical sites where r-process elements are synthesized remain mysterious: it is clear that neutron star mergers (kilonovae, KNe) contribute, and some classes of core-collapse supernovae (SNe) are also possible sources of at least the lighter r-process species. The discovery of 60Fe on the Earth and Moon implies that one or more astrophysical explosions have occurred near the Earth...
A decade long research project has revealed a chronological sequence of Australian Aboriginal rock art that spans, at least, 20,000 years.
The Kimberley region in north-western Australia is renowned for its rich concentration of rock art, traditionally believed to originate from the Pleistocene. Despite its cultural and historical importance, the direct radiometric dating of the older art...
The long-lived radionuclides Fe-60 (t$_{1/2}$=2.6 Myr) and Hf-182 (t$_{1/2}$=8.9 Myr) are sensitive monitors to the neutron environment under different stellar conditions. Production of both nuclides requires neutron fluxes high enough to compete with the decay of the shorter-lived nuclides Fe-59 (t$_{1/2}$=44 d) and Hf-181 (t$_{1/2}$=42 d) which separate Fe-60 and Hf-182 from stable isotopes...
The radionuclide $^{60}$Fe(t$_{1/2}$ = 2.6 Myr) is a tracer for recent nucleosynthesis in massive stars and core-collapse supernovae, whereas the longer-lived radionuclide $^{244}$Pu (t$_{1/2}$ = 81 Myr) is synthesized in the astrophysical r-process. The nucleosynthesis site of the r-process is heavily debated in the astrophysics community with rare supernovae and neutron star mergers being...
Radiocarbon dating plays a pivotal role in establishing reliable chronologies in both archaeological and paleoenvironmental studies, spanning over 55,000 years. Pottery, pervasive throughout the Holocene archaeological record, offers a crucial avenue for dating human activity, employing a combination of relative methods such as typology and seriation, alongside absolute techniques. Traditional...
Various nucleosynthetic processes contribute to the creation of the chemical elements in the universe. The rapid neutron capture process ($r$-process) alone produces over half of the elements heavier than iron and is uniquely capable of synthesizing the actinides. Recent $r$-process events in the solar neighbourhood can leave fingerprints in the solar system, such as the pure $r$-process...
DAMA/LIBRA (DArk MAtter/Large sodium Iodide Bulk for RAre Processes) is a low-background NaI:Tl crystal detector array in the Gran Sasso underground laboratory in Italy. It has been measuring purported dark matter signals for over two decades. DAMA/LIBRA reported an annual modulation signal in the 2 to 6 keV energy region that is claimed to be from dark matter [1]. SABRE (Sodium-iodide with...
The preservation of bone collagen at many ancient archaeological sites in Southern China is often poor, complicating the process of effective radiocarbon dating. To address this, our study has employed a method focused on extracting hydroxyproline—a non-essential, but abundant amino acid in collagen involved in human metabolism. This approach was chosen due to its presumed stability and...
The AMS technique was implemented for the first time in Spain in 2005, with the arrival at the Centro Nacional de Aceleradores (CNA, Seville) of the first compact and multi-elemental system put in the market by High Voltage Engineering Europa (HVEE, Amersfoort, The Netherlands). Since then, actinides measurement techniques have been in constant development at the CNA. To date, 236U, 237Np,...
Extant elephant species have been protected from excessive international commercial trade by the Convention on International Trade in Endangered Species of Wild Flora and Fauna at least since 1989. However, the legal protection usually allows for some exemptions, such as antiques, that might serve as a loophole for trade in modern ivory.
Comparison of the individual legislations of chosen...
This study dated the tree ring sequence ages of the upper deck, hull deck, mast holes, keel, etc. of the “Nanhai(南海) I” shipwreck using the method of AMS radiocarbon dating. The data were corrected using Bayesian methods by Oxcal calibration software. The samples representing the time of ship sinking, such as various plant seeds and animal bones, were also dated. According to the calibration...
A.J. López-Fuentes1,2, E. Chamizo2, M. López-Lora2,3, J. Mantero1, J.M. Abril4, M. Ilie5, T. Sava5, G. Ion6
1Department of Applied Physics II, E.T.S.A., University of Seville, Seville, Spain
2Centro Nacional de Aceleradores (CNA), Seville, Spain
3Department of Atomic, Molecular and Nuclear Physics, Physics Faculty, University of Seville, Seville, Spain
4Department of Applied Physics I,...
Even with annual rainfall > 2000 mm, many wildfires in alpine coniferous forests were reported in the > 3000 m-high mountains of Taiwan (up to 3952 m). Most of these historic wildfires occurred in spring, the driest season in Taiwan, demonstrating their close relationship with climatic dryness. We have undertaken extensive geomorphic surveys in the Taiwan’s high mountains and found the...
We present a brief overview of the National Electrostatics Corp. (NEC) AMS systems over the last 30 years, leading the transition from multi-MV tandems to compact sub-MV tandems, CAMS, XCAMS and UAMS, and even lower energy single-stage SSAMS and the positive ion system, PIMS.
We will also discuss three recent beamline components that are now being installed in NEC state-of-the-art AMS...
A 64-cm long core from Zolotoe Lake (51°51'28.74''N, 80°15'59.16''E) located in the ribbon forest of the Kulundinsky plain of the West Siberian Lowland of Russia has been dated with AMS 14C dating on sediment total organic carbon (TOC) samples, and 210Pb and 137Cs dating. A clear sharp peak in the 137Cs profile corresponding to 1964 CE appeared at the 12-14 cm depth. The 210Pb profile...
miDose Solutions is a growing Polish company established in 2018 following the development and patenting of innovative solutions at the Silesian University of Technology.
The Company was founded to provide a novel dose rate measurement systems, the μDOSE system, and answer the needs and specific requirements of the trapped charge dating (TCD) community. After years of gained experience, we...
In late Quaternary loess-palaeosol deposits, snail shells are often the only radiocarbon dating material available for building a chronology. However, the reliability of radiocarbon dating different small snail shells remains an open question. Here, we collected different small snail shells from a loess-palaeosol sequence located in central China to test the radiocarbon ages of snail shells....
81Kr is a cosmogenic isotope with half-life of 229 ka. Its dating range is 20-1500 ka, which covers many applications for polar ice. 81Kr can provide absolute, radiometric ages and do not rely on continuous stratigraphy. Thus it is complementary to conventional ice dating techniques and is particularly valuable for disturbed ice samples. 81Kr-dating on 200 kg blue ice samples from the Taylor...
Interferences from isobars typically restrict the applicability of AMS to selected long-lived radionuclides. The novel Ion-Laser InterAction Mass Spectrometry (ILIAMS) technique at the Vienna Environmental Research Accelerator (VERA) can overcome this limitation in many cases by highly-efficient isobar removal at eV-energies in a gas-filled radiofrequency quadrupole. The virtually complete...
Solar eruptions (solar flares and coronal mass ejections) are known to cause various space–weather phenomena in the Sun–Earth system that can have severe impacts on modern society. As the magnitude of a solar eruption increases, its frequency of occurrence decreases, but the severity of its impact increases. Therefore, it is important to understand the long-term characteristics of extreme...
The most studied actinide radionuclides to unravel contamination sources in general environmental samples have been 238Pu, 239Pu, 240Pu and 241Am. In the last few years, thanks to the development of ultra-sensitive Mass Spectrometry techniques like AMS, this list has been expanded to other less studied and minor actinides nuclides providing key information on the source terms. 236U and 237Np...
Radionuclides are ideal gauges for monitoring the energetic particle environment of the lunar surface and near sub-surface. The physics of the production mechanisms of the radionuclides and the production rates are known. The measurement of radionuclides in depth profiles from the lunar surface has allowed us to better characterize both the galactic and cosmic ray fluxes in addition to...
The Annual discharges and the ratio of 129I/236U from the nuclear reprocessing plants are different, the concentration of 129I, 236U, and the ratio of 129I/236U are novel tracers for the transit time of the Arctic Ocean circulation.
We developed a new 236U-AMS with the time-of-flight detector system at the MALT, The University of Tokyo. To improve sensitivity and decrease background by...
The well-preserved Tswaing Meteor Crater– aka Pretoria Saltpan – with a diameter of 1130 m is located ca. 40 km NNW of Tshwane (Pretoria). It has been a subject of several scientific investigations. The crater is formed on a ca. 2 Ga Nebo Granite, the acid phase, of the Bushveld Complex (Lebowa Granite Suite). The interior structure floor is not far removed from the local ground water level...
In 2011, during the Fenice11 expedition to the Tyrrhenian Sea, a total of about 350$\,$L of sea water samples were collected and prepared as large volume intercomparison sample for $^{236}$U/$^{238}$U. In this contribution, the results of the intercomparison will be presented.
All samples were filtered through several 0.45$\,\mu$m membrane filters and collected in a 400$\,$L plastic tank....
From a multi-isotope direct-AMS survey of 310 uranium ore concentrates (UOCs), 236U/238U ratios from 2x10-12 to 2x10-7 are measured. However, a range from low-10-12 to mid-10-10 is expected from directly mined natural uranium ore minerals. This upper-end discrepancy would normally be attributed to inputs of spent fuel materials, but the numerous occurrences and the lack of economic reasons to...
Understanding the hydrological changes on context of global warming is of special significance for the security and sustainable development in vast arid areas of Central Asia. The sustainability of river runoff, as the major freshwater source in arid Central Asia, is of special concerns because millions of people suffer from water stress. However, our understanding of the freshwater mechanisms...
The Guizhou Plateau is a typical subtropical mountainous karst area where carbonate rocks contain very few insoluble residues causing the slow soil production rate. Moreover, serious soil erosion leads to karst rocky desertification and land degradation in this area. Quantification of soil formation age and rate thus is vital for understanding carbonate weathering and scientifically evaluating...
Abstract: The compact AMS devices are the tendency of AMS development. Based on the previously developed air-insulated AMS, the compact AMS device with a terminal voltage of 0.25 MV has been established. In this paper, a low detection limit measurement method for 239Pu using compact accelerator mass spectrometry (AMS) has been presented. A measurement technique for 239Pu was established based...
Long-lived nuclides $^{10}$Be, $^{14}$C, $^{26}$Al, $^{36}$Cl, $^{41}$Ca, $^{90}$Sr, and $^{129}$I have been successfully detected with the 6 MV accelerator mass spectrometer at the University of Tsukuba [1]. $^{36}$Cl is one of the most difficult radionuclides to measure due to contamination with the interfering isobaric $^{36}$S. Sulfur itself is easily present in the environment, making its...
$^{129}$I is one of the AMS radionuclides which benefits most from a compact and low-energy AMS system. The interfering stable isobar $^{129}$Xe is completely suppressed as it does not form negative ions, thus high energies are not required for isobar separation in the detector. Mass separation needs to be high enough to discriminate against the stable isotope $^{129}$I. The HE side of a...
The Anthropocene is a proposed geological epoch that will mark when humans have irreversibly affected the Earth. One of the primary requirements to formally establish this is a Global Boundary Stratotype Section and Point (GSSP) or “golden spike” – a record of a planetary signal marking the new epoch’s beginning. Last July 2023, it was announced that the leading candidate for the...
Age determination of sediments in arid and hyper-arid regions poses challenges due to the absence of age-indicating fossils. As part of the collaborative research cluster 1211 of the German Research Foundation “Earth - Evolution at the Dry Limit” we are improving cosmogenic radionuclide dating in order to gain a better insight into the geological dynamics of, e.g., the Atacama Desert or the...
Radioactive iodine is a key concern for the transport and dispersion of radioactive pollutants and radiation exposure evaluation during nuclear accidents and nuclear emergency preparedness, as well as for understanding the atmospheric cycling of iodine. However, atmopsheric 129I is difficult to measure due to its low concentration in remote areas, away from nuclear pollution sources. This...
129I (T1/2 = 15.7 × 106 y) is a radionuclide whose presence in the environment changed strongly due to the emissions from the two largest nuclear fuel reprocessing plants in Europe: Sellafield (UK) and La Hague (France). Most of the 129I has been discharged to the sea, but part of it is released as gaseous 129I. Liquid discharges of 129I mostly travelled from these plants to the North Sea and...
In situ-produced Be-10 is routinely used in the mineral quartz for measuring exposure times and erosion rates. Most previous applications have focused on relatively coarse mineral grains (typically greater than 100 microns) in sandstone, quartz veins, or igneous and metamorphic rocks. Here we report Be-10 measurements from fine-grained quartz extracted from shale bedrock and sediment. Shale...
A series of analytical methods have been developed for sensitive and accurate determination of long-lived 129I, 14C, plutonium and uranium isotopes in various environmental samples, such as soil, sediment, water, air, and vegetation samples in the Xi’an AMS center using the 3MV tandem AMS, MICDAS AMS and other mass spectrometry methods. An overall investigation of artificial radioactivity in...
Terrestrial cosmogenic nuclides provide a crucial tool in geomorphology, however evaluation and correction of systematic uncertainties remains a challenge in estimating denudation rates of land surfaces. Subsurface nuclide production involves distinct processes by neutron and muons, which have different contribution ratios and attenuation lengths for accumulating any nuclides such as...
Iodine isotopes (stable 127I and long-lived radioactive 129I with half-life 15.7 million year) in natural environment have potentially various applications, utilizing as a dating tool or an index of comic-ray intensity variation with millions to 10-million-year time scale. For these purposes, iodine isotope system in natural environment should be understood comprehensively. Important issues...
Radiation exposure dose and potential health risks remain a crucial aspect of public health particularly given the use of the linear no-threshold model which postulates any exposure to radiation can result in harm. The concentration of several long-lived radionuclides has increased in the environment through human nuclear activities. Many of these radionuclides are alpha and beta emitters...
The rate of production of cosmogenic nuclides is not only related to altitude and latitude, but also to topographic occlusion and the elemental composition of rock formations. Due to the occlusion of the terrain, it is necessary to establish a shielding factor calculation model in practical geoscience applications. In this paper, five geometric shapes of terrain are considered: slope, surface...
The increasingly wide range of human activities in the nuclear field, such as nuclear weapons technologies, nuclear reactors for energy production, spent nuclear fuel reprocessing plants, and nuclear waste repositories, has correspondingly increased the importance of monitoring and preventing nuclear pollution.
In the early stages of nuclear pollution, the quantities of dispersed radioactive...
Iodine is a crucial nutrient for public health, and its presence in the terrestrial atmosphere is a key factor in determining the prevalence of iodine deficiency disorders. While oceanic iodine emissions decrease at lower sea surface temperature, the primary contributors to atmospheric iodine can vary from oceanic sources in summer to other sources in winter. However, the specific sources and...
The radiocarbon laboratory “AMS Golden Valley” was established in 2020 in Novosibirsk, Russia. At the present moment laboratory provides routine 14C analyses of various samples: collagen, cellulose, humic acids, carbonates from sediments, food soot, methane from seeps, CO2 dissolved in water etc. The main focus of the laboratory is to determine the age of archaeological artifacts by...
The ERC-funded project entitled TITANICA (A New Era of Transient Tracers in the Arctic and Atlantic Ocean) embarked on its official journey in July 2021, with the aim to decipher circulation patterns, transport timescales and mixing in the Arctic and subpolar North Atlantic oceans. The novelty of TITANICA is the use of a new set of transient radionuclide tracers (129I, 236U, 39Ar and 14C), a...
Determining the landslide type and pattern which are greatly conditioned by the lithological properties of the land surface, is vital for evaluating geo-hazard risk for different area and understanding regional landscape evolution pattern. Landslides could supply substantial deep-seated, low-nuclide debris from hillslope into channel network, resulting in a dilution of the detrital cosmogenic...
For channel incision rate determination and comparison, bedrock samples from sections of the Olifants River (n = 10) in the dry tropical/subtropical Kruger National Park, as well as samples from sections of the Orange River (n = 20), in the arid Northern Cape were collected. Using cosmogenic in-situ 10Be in pure quartz, average incision rates determined from granitic samples of the Olifants...
Over the last twenty years, the use of cosmogenic nuclides has allowed a spectacular growth in the quantification of processes in the earth sciences. Besides the field of accelerator mass spectrometry, the accurate application of these approaches implies that the nuclide production rates are well known. During the last decade, a lot of work has been done in the field of production rate...
Multiple marine terraces, presumed to have been formed by uplift with the Nankai Trough Earthquake, are recognized in the Shionomisaki area, Wakayama Prefecture. These marine terrace surfaces can be used to investigate the crustal deformation history in this area, if those abandonment ages can be determined. Surface exposure dating (SED) using cosmogenic radionuclides(CRNs) is an applicable...
Through the chemical treatment of samples with high I-129 concentrations, the workspace used to prepare samples tends to become gradually contaminated. Such contamination may lead to overestimated I-129 in accelerator mass spectrometry (AMS) analyses. Environmental contamination monitoring of I-129 from the atmosphere in sample preparation rooms was performed at ten Japanese institutions,...
CENIEH, located in Burgos, northern Spain, is dedicated to human evolution research worldwide, including Atapuerca, a world heritage archaeological site where among the oldest human fossils in Europe has been discovered. To support the needs of characterising geological and sedimentological context of archaeological sites, the institute also features a wide range of geological analysis (e.g.,...
Herein, we give an overview of the operating status and performance of the 1MV AMS system. The long-term measurements of the standard and blank samples indicated that the results for IHEG-CAGS AMS were accurate and stable and of high sensitivity.
In September of this year a 2-day MICADAS (MIni CArbon DAting System) workshop was held to discuss (1) best practices, advances, successes, and issues encountered with the MICADAS, (2) solutions and potential approaches to address any common problems, and (3) best communication mechanisms for a user group. Outcomes of the meeting and plans for a follow up workshop are presented.
During the last decades, the scientific community has dedicated efforts to expand the list of radionuclides that can be measured by the ultra-sensitive AMS techniques on either traditional or compact facilities. To date, 239Pu, 240Pu and 236U are consolidated radionuclides in AMS. In the last few years, the most minor actinides isotopes have been put in the limelight: 233U, 241Pu, 242Pu,...
The chronology from the 10th century BCE is of great importance for the archaeology of the Japanese archipelago and East Asia. We have continued AMS radiocarbon dating of Japanese trees with tree ring ages, and some of the results have been included in a calibration curve IntCal20. As a result, the shape of the calibration curve was revised from the 1st to the 3rd century CE. However, the data...
The current radiocarbon calibration curve for the northern hemisphere, IntCal20, represents a major update of the previous calibration curve, IntCal13. Over the first half of the first millennium CE, IntCal20 is based on over 550 calibration datapoints, in comparison to IntCal13, which was based on just over 100. In general, the calibration data and, thus, the two curves follow each other...
The NIES-TERRA AMS facility, the NEC 5 MV tandem Pelletron AMS, was installed in 1995 and started operation in 1997 for various environmental studies. In 2015 and 2016, we made substantial improvements to the system, such as the installation of a new type of ionizer (multi-cathode source of negative ions by cesium sputtering, MC-SNICS), reconstruction of the beamlines, and exchange of related...
Accelerator Mass Spectrometry (AMS) technique was emerged as a discipline in the 1970’s, after the demonstrating that tandem accelerators are suited to the detection of 14C in natural materials for radiocarbon age dating (14C/12C < 10E-12). Since then, over 50 rare isotopes at such low abundances, from tritium to curium, have been detected using accelerators of varying sizes. Methods are...
Institute of Geochemistry, Chinese Academy of Sciences (IGCAS), has installed a universal 1 MV AMS in February 2022. Manufactured by National Electrostatics Corporation, the United States of America, it is equipped with a 40 cathodes MC-SNICS ion source, a 90° injection magnet (mass energy product 5 amu-MeV), a model 3SDH-1 pelletron accelerator, a 90° high energy analysis magnet (mass energy...
Calculate the production rate of cosmic nuclides in a certain place in the matter, use the flux of primary particles and secondary particles of particles reaching the earth's atmosphere, use software to simulate the process of particles bombarding objects, obtain the energy spectrum of particles and secondary particles at different depths, and calculate the production rate of different...
Routine $^{14}$C analysis of user samples is performed with two accelerator mass spectrometers at AMS Golden Valley: BINP AMS facility, developed by Budker Institute of Nuclear Physics, Russia and MICADAS-28 facility, developed by IonPlus AG, Switzerland. The laboratory has international index GV and provides $^{14}$C analyses of various samples: collagen, cellulose, humic acids, carbonates...
Attributed from combination of AMS-measured cosmogenic 10Be record in loess with RTA mathematical trace method, decline of loess susceptibility in the Xifeng 0-870Ka profile is unexpectedly revealed by the uptilting of the RTA-reconstructed 0-870Ka atmospheric 10Be production rate Pr curve and is indubitably certificated by high similarities R2≈0.9 (or r=0.94) shown in the linear regression...
A significant amount of radioactive material was released into the environment after the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) on March 11, 2011, with atmospheric emissions commencing on March 12 and peaking during March 15–16 and 20–22 (TEPCO, 2012). Anthropogenic sources such as nuclear-fuel reprocessing plants had already increased the I-129 level in the environment...
Iodine-129 is a long-lived radionuclide introduced into the environment through human nuclear activities (HNAs) such as nuclear accidents, nuclear fuel reprocessing, and nuclear weapons testing. It is considered an excellent oceanographic proxy and tracer of HNA-derived radionuclide due to its biophilic nature, conservative behavior, and sufficiently long residence times in the ocean.
Here,...
In the Western Equatorial Pacific, a significant portion of ocean radioactivity is contributed by aboveground nuclear weapons tests (ANWTs) conducted in the Pacific Proving Grounds (PPG) during the 1950s. These radioactive materials can reach the Philippines through the North Equatorial Current (NEC), which splits into the Kuroshio (northward) and Mindanao (southward) currents upon hitting the...
Hadal trenches (6000-11000 m) constitute 45% of the ocean depths range and have the ecology of the deepest places on earth. The understanding of the life history of hadal trench organisms is limited due to the lack of a proper dating method. Though radiocarbon has the potential for dating modern organisms in trenches, the lack of a 14C dating method limited the application of 14C in marine...
Beijing Normal University acquired a 1MV multi-element AMS system from High Voltage Engineering Europa; the system is now commissioned after some delay. This advanced 1MV system is uniquely configured to accommodate efficient transmission of all elements from light to heavy, including an additional detector line dedicated to 10Be detection with overall beryllium ion transmission efficiency...
$^{129}I (T_{1/2} = 15.7 My)$ is present in all environmental compartments and has a very conservative behaviour in water. Its presence in the environment is mainly due to the nuclear fuel reprocessing plant discharges, whose history is relatively well-known. These characteristicsenter code here make of it an excellent hydrological tracer. For this and other applications, $^{129}I$ is one of...
The compact 14C AMS system extended for 10Be and 26Al (XCAMS) has been installed at Tianjin University for 7 years already, since October 2017. More than seven thousand samples have been successfully measured and analyzed. The cosmogenic nuclides of 14C, 10Be and 26Al have been widely applied to related fields such as earth systems and environmental sciences. The system was gradually smoothed...
In the Tono Geoscience Center, Japan Atomic Energy Agency (JAEA), the investigation of deep underground environments for R&D programs related to the geological disposal of High-Level Radioactive Waste (HLW) has been performed by using various dating systems, including Accelerator Mass Spectroscopy. The JAEA-AMS-TONO facility owns three accelerator mass spectrometers (AMS). Two of these are for...
One of the main advantages of nuclear fusion in comparison to fission is that any radioactive waste produced is future fusion reactors is expected to be low-level waste (LLW) at least 100 years after the end of its operation. The activation of the structural material would be caused by the expected high fluences of high-energy neutrons (14.1$\,$MeV) produced by the deuterium-tritium fusion...
In Romanian scientific research, there was already vast experience in the field of accelerator mass spectrometry. In 2012, this research field received a strong development boost when a new Cockcroft Walton type 1 MV HVEE tandetron AMS system was installed at the National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest. After the acceptance tests carried out by High Voltage...
DREAMS, the DREsden AMS-facility, in operation since 2011 is based on a 6 MV Tandetron (manufactured by High Voltage Engineering Europa) and shared with other research groups at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). DREAMS has been applied primarily in the measurement of cosmogenic isotopes. However, with radiocarbon not in the mix, a focal point has always been the routine...
In the frame of the PRP (Pathogen Readiness Platform) project funded through the post-pandemic Italian plan for recovery and resilience (PNRR: Piano Nazionale Ripresa e Resilienza) the installation of a new compact Accelerator Mass Spectrometry system is planned at CEDAD (Centre of Applied Physics, Dating and Diagnostics), Department of Mathematics and Physics “Ennio de Giorgi”, University of...
Over the last several decades what was originally a General Ionex Corp. Model 846 high-intensity multi-sample negative ion source has been heavily modified to become what is now the Center for AMS at Lawrence Livermore National Laboratory’s (CAMS/LLNL) general use Cs Sputter Negative Ion Sources. One of these CAMS/LLNL ion sources currently in operation at CAMS is used predominately for...
The isotope $^{129}$I, with a half-life of 15.7 million years, serves critical roles ranging from an environmental tracer of fission products to a significant marker in nuclear astrophysics. Due to its low natural terrestrial abundance (approximately one part per trillion), accelerator mass spectrometry (AMS) offers a robust method for its detection, accurately distinguishing the $^{129}$I...
The cosmogenic isotope 41Ca with a half-life of 99,000 years can serve as a dating tracer for environmental processes. Employing the atom-trap trace analysis (ATTA) method, we realized a precision of 10% on the 41Ca/Ca ratio at the level of 10−17 with the lowest measured 41Ca/Ca ratio standing at (1.99 ±0.34) ×10−17.
For 41Ca exposure dating, we have developed a 41Ca production model, which...
Iodine-129 is a long-lived radioisotope considered an excellent environmental tracer due to its unique and conservative properties. Groundwater and seawater samples collected from Boracay island, southwestern Philippines, in April 2022 were analyzed for iodine-129, iodine-127, and stable isotopes of H and O. One groundwater sample with elevated salinity suspected due to seawater intrusion was...
MALT (Micro Analysis Laboratory, Tandem accelerator, The University of Tokyo) is an ion beam analysis facility consist of a negative ion source, injection analysis system, a 5MV tandem accelerator, a high energy analysis system, and beam courses each dedicated for ion beam analysis method. Among various beam analysis techniques, AMS (Accelerator Mass Spectrometry) is one of most important. The...
Hong-Chun Li*, Tzu-Tsen Shen, Satabdi Misra, Mitwally E. M. A.
Department of Geosciences, National Taiwan University, Taipei 106319, Taiwan
The AMS 14C dating Lab (Lab code is NTUAMS) in the Department of Geosciences at the National Taiwan University was established in 2012 equipped with a 1.0 MV Tandetron Model 4110 BO-Accelerator Mass Spectrometer (AMS) made by High Voltage Engineering...
$^{14}$C is one of the most useful isotopes and has been widely utilized for radiocarbon dating in various fields, such as archaeology, environmental science, geology, and space and earth sciences. Yamagata University (YU) installed a compact accelerator mass spectrometry (YU-AMS, Fig. 1) system in March 2009 [1]. Two automated graphitization lines, AGL-I and AGL-II, were also installed in YU...
The March 2011 accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in Japan resulted in the massive release of high-volatility fission products, including $^{129}$I (8.1 GBq) and $^{131}$I (120–160 PBq). The long-lived $^{129}$I (T$_{1/2}$ = 15.7 million years) is one of the important radionuclides that we need to evaluate its migration behaviour from Japan’s land area to the marine...
The 6 MV multi-nuclide AMS system at the University of Tsukuba has been in operation for 10 years since 2014 [1]. The injector has two cesium sputtering negative ion sources: the 40-sample MC-SNICS and the MCG-SNICS gas/solid hybrid ion source. The accelerator with the 6 MV Pelletron tandem (National Electrostatics Corp, 18SDH-2) has a gas stripper tube and a foil changer with 80 foil holders...
The CEDAD-Centre of Applied Physics, Dating and Diagnostics was established at the University of Salento in 1999 in the frame of a large scale research project funded by the Italian Ministry of Research and Education. The first core of the centre was a 3 MV Tandetron accelerator (Mod. HVEE 4130HC) initially equipped with only one high energy ion implantation beamline which was then upgraded...
Since 2021, the first Czech accelerator mass spectrometry laboratory have been operating at the Nuclear Physics Institute of the Czech Academy of Sciences in Řež, near the capital city of Prague. Its primary purpose is to conduct radiocarbon measurements. The Czech Radiocarbon Laboratory (international code CRL) can provide precise results for radiocarbon dating and other applications of 14C...
The Lawrence Livermore National Laboratory’s CAMS Accelerator Facility (CAMS) has been in operation since the late 1980’s. CAMS currently encompasses three electrostatic tandem-type accelerators with pelletron charging systems, and one elevated deck AMS system. Over the years, CAMS has established AMS measurement capabilities for 3H, 7Be, 10Be, 14C, 26Al, 36Cl, 41Ca, 63Ni, 90Sr, 99Tc, 129I,...
Karst rocky desertification has been a very serious environmental issue in the southwestern China. Heavy metal elements entering the surface ecosystem through the dissolution of carbonates in such areas increases the pollution risk to the farmland soils. Here we present preliminary results of a new attempt of determining long-term soil erosion rate using isotope ratios of the meteoric...
A compact AMS was installed at Peking University in September 2004. The instrument was the fourth of newly developed low energy compact Pelletron model 1.5SDH AMS manufactured by the National Electrostatics Corp. Here we reflect major instrumental improvements and applications associated with the instrument over the past 20 years. The 500kV compact AMS was upgraded for 10Be measurements in two...
Thorium isotopes Th-234, Th-230 and Th-228 are important tracers for estimating carbon fluxes in the ocean via the biological pump. However, conventional radiological methods for Th-230 and Th-228 in seawater require large-volume samples (100-1000 L), limiting the large-scale application of Th isotopes in carbon sink accounting. This study aims to develop an accelerator mass spectrometry (AMS)...
Hadal trenches are unique geological and ecological systems located along subduction zones. Earthquake-triggered turbidites act as efficient transport pathways of organic carbon (OC), yet remineralization and transformation of OC in these systems are not comprehensively understood. Here we measure concentrations and stable- and radiocarbon isotope signatures of dissolved organic and inorganic...
In this study, the detection limits for Pu, U, and Am isotopes are presented, demonstrating the ETH MILEA system's capability to identify these isotopes at ultra-trace levels. Additionally, the impact of varied matrix compositions, specifically iron and niobium content, on the detection efficiency of these actinides was investigated. Larger matrices were observed to be advantageous for...
High lake levels across the Tibetan Plateau (TP) have attracted much attention, but the mechanisms driving the lake level rises are still debated. Dramatic lake expansions over the past decades are mainly ascribed to the additional water supply from accelerated glacial melting and precipitation increasing. Throughout the late Quaternary higher lake levels have been attributed primarily to...
The authenticity of traditional Chinese medicinal herbs refers to the superior quality and significant efficacy of herbs from specific regions due to unique geographical and climatic factors. This concept holds an important place in traditional Chinese medicine. Scientific analysis and testing are crucial for ensuring the quality of medicinal herbs and enhancing clinical...
English oak is the most common timber found in Historic Buildings in England, although conifer is used widely in the post medieval period and fine-grained oak panels were imported from around the Baltic from the middle ages. The network of ring-width reference chronologies for English oak over the past millennium is generally robust, and it is unusual to find long (> 100 rings) and...
$^{236}$U is a rare isotope of uranium, naturally occurring with an abundance of less than 100 parts per trillion. The ability to detect it and make isotopic ratio measurements has applications ranging from nuclear forensics and nonproliferation to energy production and environmental protection. Currently, Accelerator Mass Spectrometry (AMS) is the only technique sensitive enough to accurately...
The southern Okhotsk Sea is an excellent fishing ground, producing 352 kton year$^{-1}$ of scallops, crabs, salmon, etc. Fed by the Soya Warm current (SWC, high salinity) and the East Sakhalin Current (ESC, cold and low salinity), surface water of the southern Okhotsk can be grouped into Coastal and Offshore areas.
The Cold Water Belt (CWB) is formed by the upwelling of cold subsurface...
A single-stage accelerator mass spectrometer at the Atmosphere and Ocean Research Institute, The University of Tokyo was installed in 2013 and has been running stably for the past 10 years. Various types of samples have been analyzed, including geology, biology, oceanography, archaeology, etc., in active collaboration with national and international institutions. Precision for 14C/12C...
In order to investigate the spatial distribution and source of 236U in the Beibu Gulf, we collected and analyzed 36 surface sediments using accelerator mass spectrometry (AMS). Prior to AMS measurement, the abundance of 238U,235U and 234U were determined by inductively coupled plasma mass spectrometry (ICP-MS). By combining the counts of 234U and 236U in the AMS measurement with the value of U...
ASTER AMS facility, part of the LN2C (National Laboratory for Cosmogenic Nuclides) is involved in its own beam line development to fulfil the stringent requirements of the AMS technic and the always increasing quality measurements required by the Geosciences community applications. Since the acceptance tests in March 2007, routine measurement conditions for the long-lived radionuclides 10-Be...
The Radiocarbon Laboratory of the Fluminense Federal University (LAC-UFF) has been pivotal in radiocarbon dating by Accelerator Mass Spectrometry and its applications in Latin America since its inception in 2009 (Anjos et al. 2013; Macario et al. 2013; 2015). Over the past 15 years, LAC-UFF has engaged in diverse research activities and collaborations. These have spanned cultural and natural...
Alerce (Fitzroya cupressoides) is rare and long-lived cypress growing in southern Chile and adjacent Argentina. Considerable effort has been devoted to developing millennium-long tree-ring chronologies of Alerce, and this has led to a 5682-year-long tree-ring width chronology, which is the longest for the Southern Hemisphere. In this study, tree-ring dating was conducted using Alerce...
Constraining the sources, transport, and burial of OC in marine sediments is of fundamental importance for understanding the carbon cycle on a range of spatial and temporal scales. Marginal seas receive substantial terrestrial inputs from rivers and comprise hotspots for both organic carbon (OC) burial and remineralization. However, much remains unknown about factors that control the sources,...
We report here the progress of the sealed tube zinc reduction method for graphitization over the past 22 years at the W. M. Keck Carbon Cycle AMS facility (KCCAMS) at the University of California, Irvine, USA. Since the publication of the method in 2007, we have significantly improved and expanded this technique. First, we have further decreased the background associated with combustion and...
Ala Aldahan1 and Xiaolin Hou2
1Department of Geosciences, United Arab Emirates University, Al Ain, UAE
2Xi’an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
Göran Possenrt was a remarkable, innovative and sympathetic scientist who was always open to new challenges and endeavors. His sense of humor let him engage easily with everyone and he was an...
In February 2024, the radiocarbon community suffered a great loss with the passing of Ingeborg Levin, a prominent figure in the field.
This tribute commemorates her scientific journey, which began in 1978 with her diploma thesis "Regional Modelling of Atmospheric CO2 Based on C-13 and C-14 Measurements." Throughout her career, she focused on studying various trace gases, such as CH4, N2O,...
A method of hydrogen sulfide removal in water (for DIC radiocarbon analysis) or carbon dioxide gas was investigated. By using a silver nitrate solution in diluted nitric acid in a gas wash device, or a trap filled with silver nitrate impregnated silica gel, the hydrogen sulfide was easily removed from the carbon dioxide. The cleaned CO2 is pure enough to get reduced by hydrogen on the iron...
10Be and 26Al sample preparation at the GXNU-AMS laboratory
Kaiyong Wu1, Hongtao Shen1, 2*, Linjie Qi1, He Ouyang1, Guofeng Zhang1, Junsen Tang1, 2, Dingxiong Chen1, Xinyi Han1, Xinya Huang1, Lingrong Du1, Weixin Chen1, Wenqiao Liu1
1. College of Physics and Technology, Guangxi Normal University, Guilin Guangxi 541004, China
2. Guangxi Key Laboratory of Nuclear Physics and Nuclear...
Natural landscape evolution is strongly linked to the climatic and tectonic settings of a region. Consequently, indicators of landscape changes through time can provide vital information on climate and tectonic changes in the past. Be-10 data from arid regions, although challenging due to the difficulties of finding well preserved archives, can contribute to a better understanding of climate...
10Be AMS MEASUREMENTS AND CHRONIC BERYLLIUM DISEASE (CBD)
Kunihiko Nishiizumi, Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450, USA. (kuni@berkeley.edu)
Beryllium and Be compounds, especially inhalation of very small particles or fumes, are known to be extremely toxic materials. Although the occupations with the highest risk are likely Be mining and machining,...
Seawater circulation and interaction are important processes for pollutant dispersion and environmental and climate change. Salinity and temperature are the conventional parameters, which were widely used for the identification of water masses and circulation in the oceans. Generally, small differences in these two parameters are difficult to detect, which makes precise and accurate...
A method for preparing gas samples was established in Guangxi Normal University. The method consists of three parts: introducing nitrogen to exhaust the impurity, releasing the gas and circulating CO2 , purifying CO2 and graphitization. A series of atmospheric samples were prepared to verify the feasibility and stability of this method. Moreover, the carbon content corresponding to the...
The passing of Göran Possnert in October 2022 marked a significant loss to the cosmogenic radionuclides community. His pioneering work laid the foundation for many advancements in this area, and his contributions continue to influence current research and methodologies. The cosmogenic radionuclide group in Lund, led by Raimund Muscheler, has cooperated with Göran Possnert since 2007, focusing...
Tree-ring cellulose is a commonly used material for radiocarbon analysis. Extracting cellulose is labor-consuming and several devices that enable batchwise extraction have been developed. However, these devices bear the risk of sample contamination. The present study describes a new device which improves upon two aspects of currently available devices. First, to prevent...
The English Channel (the Channel) and the Celtic Sea represent a major transport pathway of Atlantic water to the North Sea, with anthropogenic I-129 added to the water parcels. The major source of this I-129 is the liquid discharges from the La Hague nuclear reprocessing facility of I-129 into the Channel that have been going on for the last 60 years, with an estimated total amount exceeding...
GANA (Guangxi Accelerator for Nuclear Analysis) is a new 3.0 MV universal Accelerator Mass Spectrometer (AMS) at Guangxi Normal University (GNU), and it supports the analysis of elements ranging from 10Be to 244Pu at 3 MV terminal voltage. Manufactured by High Voltage Engineering Europa B.V., the Netherlands, GANA is equipped with a 50-sample ion source, a high-resolution 120-degree injection...
Modern AMS instruments are still following design concepts of the pioneering experimental setups as invented during the early times of AMS. However, measurement procedures have undergone a continuous evolution. Groundbreaking progress was made when molecular isobaric interferences could be eliminated by collisional interaction of swift ions with the stripper gas atoms. Radiocarbon detection,...
The mass region between 90 and 100 amu is home to several long-lived radionuclides that are interesting for various applications of AMS. Two examples are $^{93}$Zr, and $^{99}$Tc with half-lives of ~1.6 Ma, and ~211 ka respectively. Both isotopes are high-yield fission products and were produced and distributed in the environment by atmospheric nuclear weapons tests and nowadays are produced...
Concentrations of the anthropogenic radionuclide $^{99}$Tc (t$_{1/2}$ = 2.1$\times$ 10$^5$ yrs) have been extensively studied in the Irish Sea, where the Sellafield reprocessing plant is responsible for high concentrations of 2$\times$ 10$^9$ atoms/ml. However, a comprehensive understanding of its global distribution and physico-chemical behavior in the environment remains limited. The...
The 10Be/7Be ratio is a sensitive tracer for the study of atmospheric transport, particularly with regard to stratosphere-troposphere exchange. Measurements with high accuracy and efficiency are crucial to 7Be and 10Be tracer studies. Full stripping method of 7Be have been carried out by few larger AMS. However, for low energy AMS that is difficult to obtain efficient full stripping Be, the...
NAUTILUS (NAval Ultra-Trace Isotope Laboratory Universal Spectrometer) combines Secondary Ion Mass Spectrometry (SIMS) with a Single Stage 300kV Accelerator Mass Spectrometer system (SSAMS) to produce a single setup unlike any other in the world for spatially resolved trace-element and isotope analysis [1]. Initially designed and built at the United States Naval Research Laboratories (NRL), it...
Strontium-90 ($^{90}$Sr) is an anthropogenic radionuclide, which, due to its radiological relevance, has been most intensively monitored in the past. In terms of initial activity, over 630 PBq of this radionuclide have been distributed globally from stratospheric fallout of bomb-testing, and there are more localized contributions from tests, accidents, and releases from reprocessing plants. In...
The long-lived noble-gas isotope 81Kr is the ideal tracer for old water and ice with ages of 0.1 – 1 million years, a range beyond the reach of 14C. 81Kr-dating, a concept pursued over the past six decades, is now available to the earth science community at large. This is made possible by the development of the Atom Trap Trace Analysis (ATTA) method, in which individual atoms of the desired...
The Southern Ocean is suitable for detecting water masses containing anthropogenic $^{129}$I (T$_{1/2}$: 15.7 million years) tracer since $^{129}$I in the Southern Ocean is 3–6 orders of magnitude lower than that in the Northern Hemisphere. This study aimed to clarify seawater circulation in the Southern Ocean by vertical cross-sectional observations of dissolved $^{129}$I and water mass...
The Arctic, a region highly sensitive to global climate change, has experienced a temperature increase exceeding four times the global average rate since the onset of the industrial era. Concurrently, warmer and saltier Atlantic water is encroaching further northward into the Arctic Ocean, driving the phenomenon known as "atlantification." These shifts have led to significant Arctic sea ice...
Over the last deglaciation, ventilation of ocean circulation has been key regulators of deep-sea carbon release, controlling climate change on centennial to millennial time scales. However, paleoceanographic reconstructions documenting changes in deep-ocean ventilation using 14C- foraminifera dating, may bear multidimensional explanations, obfuscating the roles of ocean ventilation played on...
The Southern Atlantic continental shelf of Africa is an almost blank area regarding available information on the presence of anthropogenic radionuclides, namely actinides. The coast of Namibia, part of the northern Benguela Upwelling System, was the target of the first two studies reporting 236U, 237Np, 239Pu and 240Pu in seawater [1,2]. The obtained 236U and 237Np inventories and the...
Uranium-233 (233U) and uranium-236 (236U) in the environment mainly originate from human nuclear activities. Based on the long half-lives and high solubility of uranium, 236U and 233U can be used as powerful tracers for the investigation of oceanographic and environmental processes. However, insufficient work limits the understanding of the source items of anthropogenic 233,236U in the South...
Radionuclides present in the marine environment predominantly stem from human activities, notably emanating from nuclear fuel reprocessing plant and nuclear weapons testing. Notably, Sellafield and La Hague facilities in Europe have been significant sources of 129I emissions into the Atlantic Ocean. Subsequently, 129I transported via ocean currents reaching the Canada...
For its ultimate success, the zero-pollution ambition of the European Green Deal requires highly sensitive and state-of-the-art detection techniques to determine ultra-low amounts of pollutants in the environment. Mass spectrometry has become a key method for the determination of non-radioactive polluting elements, and is also of increasing importance for the detection of long-lived...
Actinide-AMS has grown into an important discipline for environmental and geological sciences, for oceanography, but also nuclear (astro)physics. Nuclear data requests in nuclear physics continue to challenge the present limits in accuracy and abundance sensitivity of actinide detection. Exploring these limits is the primary motivation of this presentation.
In recent years, significant effort...
Recent studies indicate that the Arctic is warming up to four times faster than the global ocean. This accelerated warming is partly due to an increased influx of warm Atlantic waters into the Arctic basin. The Santa Anna Trough (SAT) is a strategically important location within the Arctic Ocean, where the two main Atlantic water branches—the Barents Sea Atlantic Waters (BSAW) and the Fram...
