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The issue of radiation exposure as a potential cause of cerebrovascular disease raises many concerns. The aim of the present study was to investigate the epidemiology of stroke and transient ischemic attacks (TIA) along with the associated risk factors among the population of East Kazakhstan exposed to ionising radiation from the former Semipalatinsk Nuclear Test Site (SNTS) in comparison with the unexposed population of the same region. This 5-year retrospective cross-sectional study included the data on 10,970 patients, of whom the majority (62.3%) suffered from ischemic stroke, 11.7% had hemorrhagic stroke and the remaining 26.0% had TIA. At the moment when stroke/TIA happened, exposed patients were younger than the unexposed (mean age 63 years versus 64 years, p

The Christy Gadget is the informal name for the plutonium device detonated in the Trinity test on July 16, 1945. In September 1944, Robert Christy, working in the theoretical implosion group, propo...

On July 16, 1945, the Trinity nuclear test exploded in the desert near Alamogordo, NM. A variety of new diagnostic experiments were fielded in an effort to understand the detailed performance of the nuclear device. This article describes a series of radiochemical experiments that were designed to measure the efficiency and neutron fluence of the test. These experiments, and the scientists who led them, laid the foundation of weapons radiochemistry for decades to come.

Apartheid South Africa’s nuclear related activities in Southern Africa have a long history. Apart from, inter alia, the development and existence of at least six nuclear devices, South Africa operated a nuclear test site in the Kalahari Desert on the borders of Botswana, utilised uranium from Southwest Africa (now independent Namibia) as its Class C Mandate and employed a nuclear deterrent strategy in response to Soviet support for Angola and liberation movements in the region. This elicited responses from the so-called Frontline States as well as the members of the Southern African Development Community (SADCC). Therefore, the purpose of this intended contribution is to determine the extent of South Africa’s nuclear activities as well as its impact on the region. Based on archival research, the article intends to make a contribution to the study of the region, the evolution of regional integration in Southern Africa and Cold War studies in Southern Africa., As atividades nucleares da África do Sul durante o regime do Apartheid têm longa história. Além do desenvolvimento e da existência de ao menos seis ogivas, a África do Sul operava um local de testes no Deserto do Kalahari nas fronteiras com Botswana, utilizava urânio da África do Sudoeste (hoje, a independente Namíbia) através de seu mandato datado da Liga das Nações e lançava mão de uma estratégia de deterrência nuclear em resposta ao apoio soviético a Angola e os movimentos de libertação da região. Isto motivou respostas dos denominados Estados da Linha de Frente, bem como de membros da Comunidade do Desenvolvimento da África Austral (SADCC, sigla em inglês). Assim, o objetivo desta contribuição é determinar a extenção das atividades nucleares sul-africanas, bem como seus impactos na região. Baseado em pesquisa em fontes primárias, o artigo busca contribuir para o estudo da região, a evolução da integração regional na África Austral e os estudos quanto à Guerra Fria no sul do continente africano.

The article represents the bibliometric analysis of the documentary corpus devoted to studying the Semipalatinsk nuclear test site selected of the database Russian Science Citation Index. It shows the publication dynamics over a thirty-year period, the specific structure of the documentary corpus; revels that the documents are thematically structured as follows: research of the medical and biological consequences of radiation exposure (genetic consequences of ionizing radiation exposure; diseases induced by radiation exposure); assessment of the consequences of nuclear tests for the environment (environmental monitoring, radiation situation, pollution of separate environment elements), historical and socio-legal aspects of investigating the test site activity consequences.

Toxique: Enquête sur les essais nucléaires français en Polynésie, by Sébastien Philippe and Tomas Statius, and the Moruroa Files microsite. Paris: PUF/Disclose, 2021. 192 pages. ISBN 9782130814849https://moruroa-files.org/ THE COMBINATION of nuclear expertise (Sebastien Philippe), inquisitive journalism (Tomas Statius) and the investigative approach by Interprt (a collective of architects specialising in the forensic analysis of environmental crimes) of around 2000 declassified French government documents in 2013 called the Moruroa Files, resulted in the explosive book Toxic about what was already known to the Ma’ohi Nui (French Polynesia) people. That since 1966 (55 years ago), the French government has consistently lied about and concealed the deadly consequences of their nuclear tests, which they now seem to acknowledge (French admit nuclear test fall out, 2006), to the health of the populations and their environment.

The recovery of seismic source parameters requires the use of calibrated velocity models. Although at long periods it is possible to use relatively simple plane-layered models, calibration is still needed to better constrain source parameters. For the Democratic People’s Republic of Korea (DPRK) nuclear tests, this is particularly true when considering the use of seismic stations in Japan where paths cross the Sea of Japan. In this study, we perform forward waveform modeling to calibrate velocity structures. We show that we can arrive at a set of models that minimizes Rayleigh group-velocity anomaly at stations located in China, South Korea, and Japan. Overall moment tensor capability with the new models is improved such that cross-correlation analysis of the 20–50 s period waveforms recovers the true time alignment of the data, enabling better automated source analysis. We performed source-type inversions for the moment tensor jointly for long-period regional waveforms and regional and teleseismic P-waves polarity data for the latest and largest DPRK nuclear test and examine event discrimination/screening capability, scalar moment, and yield estimates with uncertainty. We present the models for improved seismic source modeling of the region.

Seventy-six years after the atomic bombs exploded over Hiroshima and Nagasaki, the world continues to face challenges to the existing arms control framework, part of the broader problem of the stagnation of multilateralism. There is a desperate need to reinvent the architecture of nuclear disarmament. While it seems almost impossible for the political deadlock to be broken with regard to entry into force of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), the power of science continues to create a unique avenue for confidence-building measures (CBMs) to meet the needs of both nuclear-weapon states and non-nuclear-weapon states. This paper re-examines the value of science as a tool for arms control verification by separating the issue of the CTBT’s non-entry into force from the immediate application of its verification regime. The progress of nuclear-test-ban monitoring can be measured against scientific indicators, irrespective of the status of the remaining Annex II countries. The CTBT has already practically satisfied its core function of monitoring nuclear testing with the existing structure. The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization has been progressing as an agent of CBMs, the development of civilian and scientific applications of the verification regime, and a capacity-building effort to attract more states to join the cause, and by doing so, sustaining nuclear-test-ban moratoriums.

The 3 September 2017 Mw 5.2 North Korean underground nuclear test (DPRK2017) is the largest man-made explosion with surface displacements observed by Synthetic Aperture Radar (SAR) and showed as much as 3.5 m of horizontal permanent deformation. Although regional distance waveform-based seismic moment tensor (MT) inversion methods successfully identify this event as an explosion, the inverted solutions do not fit the SAR displacement field well. To better constrain the source, we developed an MT source-type inversion method that incorporates surface ground deformation (accounting for free-surface topography), regional seismic waveforms, and first-motion polarities. We applied the source-type inversion over a grid of possible source locations to find the best-fitting location, depth, and point-source MT for the event. Our best-fitting MT solution achieves ∼70% horizontal geodetic fit, ∼80% waveform fit, and 100% fit in the first-motion polarities. The joint inversion narrows the range of acceptable source types improving discrimination, and reduces the uncertainty in scalar moment and estimated yield. The method is transportable and can be applied to other types of events that may have measurable geodetic signals such as underground mine collapses and volcanic events.

South Korea deployed the Terminal High Altitude Area Defense (THAAD) antimissile system in response to North Korea’s nuclear test, leading to the Chinese government’s opposition to THAAD, citing na...

Since 2006 to 2017 the Security Council has passed a resolution on North Korea's nuclear test act. Article 25 of the UN Charter states that Members of the United Nations agree to accept and implement the decisions of the Security Council in accordance with this Charter. North Korea as a UN member state that obtained the UN Security Council Resolution is obliged to implement the sanctions resolution. However, the sanctions contained in the resolution did not make North Korea stop its nuclear program and it shows North Korea's noncompliance with UN Security Council resolutions. Implications accompanying any denial by North Korea against the UN Security Council resolution which in general affects four fields, namely the fields of economy, politics, defense and international cooperation. In addition to non-military sanctions, the Security Council under chapter VII Article 42 of the UN Charter can impose military sanctions where possible, the Security Council can also impose sanctions through the UN General Assembly on its recommendation to suspend the rights of UN membership) and expulsion of a country from UN membership)., Sejak tahun 2006 hingga tahun 2017 Dewan Keamanan telah mengeluarkan resolusi atas tindakan uji coba nuklir Korea Utara. Pasal 25 Piagam PBB menyatakan bahwa Anggota-anggota Perserikatan Bangsa-Bangsa menyetujui untuk menerima dan menjalankan keputusan-keputusan Dewan Keamanan sesuai dengan Piagam ini. Korea Utara sebagai negara anggota PBB yang memperoleh Resolusi Dewan Keamanan PBB wajib melaksanakan sanksi resolusi. Namun sanksi yang tertuang dalam resolusi tidak membuat Korea Utara menghentikan program nuklirnya dan hal ini menunjukkan sikap ketidakpatuhan Korea Utara terhadap resolusi Dewan Keamanan PBB. Implikasi hukum menyertai setiap pengingkaran yang dilakukan Korea Utara terhadap resolusi Dewan Keamanan PBB yang secara garis besar berpengaruh pada empat bidang yakni bidang ekonomi, politik, pertahanan dan kerjasama internasional. Selain sanksi non-militer, Dewan Keamanan berdasarkan BAB VII Pasal 42 Piagam PBB dapat memberikan sanksi militer jika memungkinkan untuk dilakukan, Dewan Keamanan juga dapat memberikan sanksi melalui Majelis Umum PBB atas rekomendasinya berupa penangguhan hak-hak keanggotaan PBB dan pengusiran suatu negara dari keanggotaan PBB.

This study investigates the impact of North Korea’s nuclear tests on Asian stock markets. Two approaches are used separately in order to identify how stock market returns and volatilities change immediately after the nuclear tests. We find that the Chinese stock market tends to be more sensitive to unexpected shocks from North Korea’s nuclear tests than other Asian stock markets. However, relatively, the Japanese stock market is little influenced by the nuclear tests though Japan is not only geographically close to North Korea but also politically vigilant to North Korea’s nuclear threats. Also, we find that strengthened return correlations (linearity) do not necessarily increase stock return volatilities.

In May 1955, the United States conducted its first and only deep-water nuclear test. Codenamed Operation Wigwam, the test was officially conducted to determine the effectiveness of a nuclear device...

Relevance. The main source of radionuclide contamination in Kazakhstan is the Semipalatinsk nuclear test site (SNTS), where more than 460 nuclear explosions were made. There are still people living in some areas of the SNTS. The source of radionuclides entering the human body is animal food. The aim of the study was to study the content of 137 Cs and 90 Sr radionuclides in cattle meat and their impact on public health in areas close to the SNTS. Materials and methods. The data on the content of radionuclides were obtained at the Semipalatinsk Regional Veterinary Laboratory of the East Kazakhstan Region. The object of the study was meat of cattle (cattle) (67 samples) obtained in Abai, Borodulikhinsky, Zharminsky, Beskaragaysky districts and the city of Semipalatinsk, East Kazakhstan region, adjacent to the SNTS. The retrospective of the analyzed indicators was 10 years (1991-2000). The sources of information on the incidence of the entire population in the regions of East Kazakhstan region were data obtained from the Republican Center for Electronic Health for the period 2000-2015. Mathematical and statistical processing of the results was carried out using the applied statistical program Statistica-10. Results. The average content of 137 Cs in cattle meat was 0.15 Bq/kg, and 90 Sr - 0.11 Bq/kg. The dynamics revealed a 1.9-fold decrease in the level of 137 Cs and a 2-fold decrease in the level of 90 Sr. The consumption of cattle meat by residents was 14.7%. The average morbidity level of diseases of the musculoskeletal system was 3305 ppm. The morbidity of endocrine system diseases increased 1.4 times in dynamics. The morbidity level of diseases of the digestive system was 3358.9 ppm and decreased by 24.6% in dynamics. A correlation was found between the consumption of cattle meat and the morbidity level of diseases of the musculoskeletal system r=0.78. Conclusions. The study showed a positive trend of reducing the level of radionuclides in cattle meat among the studied regions. There was an increase in the average morbidity level of diseases of the musculoskeletal system by 1.2 times, and the endocrine system by 1.4 times. There is a trend to reduce the morbidity of diseases of the digestive system in the population of the studied regions. The revealed relationship between the consumption of cattle meat and the incidence of the musculoskeletal system diseases requires further study and monitoring.

In this article, we analyzed the effects of radioactive contamination from the Semipalatinsk nuclear test site on food choices in Kazakhstan. Nearly 90% of citizens in Kazakhstan knew their health had been affected by radioactive material from the nuclear test site, with more than 50% of citizens still confirming the safety of foodstuffs regarding radioactive materials when purchasing food. However, citizens in the vicinity of the nuclear test site did not take countermeasures against internal exposure due to declining fear of radioactivity, despite refraining from purchasing food from near the nuclear test site. More than 80% of Kazakhstan understood that exposure to radioactive materials was both external and internal. Further, Kazakhs were more aware of the effects of internal exposure on the human body than either Ukrainians or Japanese. Elderly people who remembered the times when nuclear tests had been conducted were aware of radioactive materials in food. High-income individuals took measures to control radioactive contamination in consideration of their nutritional balance, while low-income individuals refrained from purchasing food from near the nuclear test site as a means of controlling potential contamination. In Kazakhstan, more than 60% of citizens did not take measures against internal exposure, but the number of citizens who were concerned about radioactive materials was much higher than in either Ukraine or Japan. In Kazakhstan, 30–40% of citizens, particularly women, would buy at least 20% more if foodstuffs with lower than the regulated level of radioactive materials were sold.

The complex postdetonation geologic structures that form after an underground nuclear explosion are hard to constrain because increased heterogeneity around the damage zone affects seismic waves that propagate through the explosion site. Generally, a vertical rubble-filled structure known as a chimney is formed after an underground nuclear explosion that is composed of debris that falls into the subsurface cavity generated by the explosion. Compared with chimneys that collapse fully, leaving a surface crater, partially collapsed chimneys can have remnant subsurface cavities left in place above collapsed rubble. The 1964 nuclear test HADDOCK, conducted at the Nevada test site (now the Nevada National Security Site), formed a partially collapsed chimney with no surface crater. Understanding the subsurface structure of these features has significant national security applications, such as aiding the study of suspected underground nuclear explosions under a treaty verification. In this study, we investigated the subsurface architecture of the HADDOCK legacy nuclear test using hybrid 2D–3D active source seismic reflection and refraction data. The seismic data were acquired using 275 survey shots from the Seismic Hammer (a 13,000 kg weight drop) and 65 survey shots from a smaller accelerated weight drop, both recorded by ∼1000 three-component 5 Hz geophones. First-arrival, P-wave tomographic modeling shows a low-velocity anomaly at ∼200 m depth, likely an air-filled cavity caused by partial collapse of the rock column into the temporary postdetonation cavity. A high-velocity anomaly between 20 and 60 m depth represents spall-related compaction of the shallow alluvium. Hints of low velocities are also present near the burial depth (∼364 m). The reflection seismic data show a prominent subhorizontal reflector at ∼300 m depth, a short-curved reflector at ∼200 m, and a high-amplitude reflector at ∼50 m depth. Comparisons of the reflection sections to synthetic data and borehole stratigraphy suggest that these features correspond to the alluvium–tuff contact, the partial collapse cavity, and the spalled layer, respectively.

The 137Cs bulk deposition samples measured in samples collected at Cluj-Napoca in 1965–1985 are analysed and compared with published 137Cs deposition data from New-York, St. Petersburg, Helsinki and Bratislava covering partially/totally the period 1955–1985. A total 137Cs deposition of 4.2 ± 0.9 kBq/m2 at Cluj-Napoca is estimated for 1955–1985 based on the comparison of available data. The signature of the atmospheric nuclear tests performed in 1977–1980 is presented using the monthly measured bulk depositions of 106Ru, 125Sb, 137Cs and 144Ce (1978–1982) and 95Zr, 103Ru, 141Ce for the year 1981, following the last atmospheric nuclear test of October 16, 1980.

The National Cancer Institute study of projected health risks to New Mexico residents from the 1945 Trinity nuclear test provides best estimates of organ radiation absorbed doses received by representative persons according to ethnicity, age, and county. Doses to five organs/tissues at significant risk from exposure to radioactive fallout (i.e., active bone marrow, thyroid gland, lungs, stomach, and colon) from the 63 most important radionuclides in fresh fallout from external and internal irradiation were estimated. The organ doses were estimated for four resident ethnic groups in New Mexico (Whites, Hispanics, Native Americans, and African Americans) in seven age groups using: (1) assessment models described in a companion paper, (2) data on the spatial distribution and magnitude of radioactive fallout derived from historical documents, and (3) data collected on diets and lifestyles in 1945 from interviews and focus groups conducted in 2015–2017 (described in a companion paper). The organ doses were found to vary widely across the state with the highest doses directly to the northeast of the detonation site and at locations close to the center of the Trinity fallout plume. Spatial heterogeneity of fallout deposition was the largest cause of variation of doses across the state with lesser differences due to age and ethnicity, the latter because of differences in diets and lifestyles. The exposure pathways considered included both external irradiation from deposited fallout and internal irradiation via inhalation of airborne radionuclides in the debris cloud as well as resuspended ground activity and ingestion of contaminated drinking water (derived both from rivers and rainwater cisterns) and foodstuffs including milk products, beef, mutton, and pork, human-consumed plant products including leafy vegetables, fruit vegetables, fruits, and berries. Tables of best estimates of county population-weighted average organ doses by ethnicity and age are presented. A discussion of our estimates of uncertainty is also provided to illustrate a lower and upper credible range on our best estimates of doses. Our findings indicate that only small geographic areas immediately downwind to the northeast received exposures of any significance as judged by their magnitude relative to natural radiation. The findings presented are the most comprehensive and well-described estimates of doses received by populations of New Mexico from the Trinity nuclear test.

The Trinity nuclear test was detonated in south-central New Mexico on 16 July 1945; in the early 2000s, the National Cancer Institute undertook a dose and cancer risk projection study of the possible health impacts of the test. In order to conduct a comprehensive dose assessment for the Trinity test, we collected diet and lifestyle data relevant to the populations living in New Mexico around the time of the test. This report describes the methodology developed to capture the data used to calculate radiation exposures and presents dietary and lifestyle data results for the main exposure pathways considered in the dose reconstruction. Individual interviews and focus groups were conducted in 2017 among older adults who had lived in the same New Mexico community during the 1940s or 1950s. Interview questions and guided group discussions focused on specific aspects of diet, water, type of housing, and time spent outdoors for different age groups. Thirteen focus groups and 11 individual interviews were conducted among Hispanic, White, and Native American participants. Extensive written notes and audio recordings aided in the coding of all responses used to derive ranges, prevalence, means, and standard deviations for each exposure variable for various age categories by region and ethnicity. Children aged 11–15 y in 1940s or 1950s from the rural plains had the highest milk intakes (993 mL d(−1)), and lowest intakes were among 11- to 15-y-olds in mountainous regions (191 mL d(−1)). Lactose intolerance rates were 7–71%, and prevalence was highest among Native Americans. Meat was not commonly consumed in the summer in most communities, and if consumed, it was among those aged 11-15 y of age or older who had relatively small amounts of 100-200 g d(−1). Most drinking and cooking water came from covered wells, and most homes were made of adobe, which provided more protection from external radiation than wooden structures. The use of multiple approaches to trigger memory and collect participant reports on diet and other factors from the distant past seemed effective. These data were summarized, and together with other information, these data have been used to estimate radiation doses for representative persons of all ages in the main ethnic groups residing in New Mexico at the time of the Trinity nuclear test.

North Korea conducted the sixth underground nuclear test on September 3, 2017 at the Punggye-ri Nuclear Test Site (NTS). In contrast to the previous five nuclear tests, several induced earthquakes occurred around the NTS after the sixth nuclear test and this may have caused radioxenon leakages at the site. Considering these reported earthquakes, we performed atmospheric dispersion simulations on some radioxenon emission scenarios for this event using our Lagrangian Atmospheric Dose Assessment System (LADAS) model by employing the Unified Model (UM) based numerical weather prediction data produced by the Korea Meteorological Administration (KMA). To find out possible detection locations and times, we combined not only daily and weekly based delayed releases but also leakages after the reported earthquakes around the NTS to create emission scenarios. Our simulation results were generally in good agreement with the measured data of the Nuclear Safety and Security Commission and International Monitoring System (IMS) stations operated by the Comprehensive nuclear Test-Ban-Treaty Organization (CTBTO).

The Leo Brady Seismic Network (LBSN, originally the Sandia Seismic Network) was established in 1960 by Sandia National Laboratories to monitor underground nuclear tests (UGTs) at the Nevada National Security Site (NNSS, formerly named the Nevada Test Site). The LBSN has been in various configurations throughout its existence, but it has generally been comprised of four to six stations at regional distances (∼150–400 km) from the NNSS with approximately evenly spaced azimuthal coverage. Between 1962 and the end of nuclear testing in 1992, the LBSN—and a sister network operated by Lawrence Livermore National Laboratories—was the most comprehensive United States source of regional seismic data of UGTs. Approximately 75% of all UGTs performed by the United States occurred in the predigital era. At that time, LBSN data were transmitted as frequency-modulated (FM) audio over telephone lines to a central location and recorded as analog waveforms on high-fidelity magnetic audio tapes. These tapes have been in dry temperature-stable storage for decades and contain the sole record of this irreplaceable data; full waveforms of LBSN-recorded UGTs from this era were not routinely digitized or otherwise published. We have developed a process to recover and calibrate data from these tapes. First, we play back and digitize the tapes as audio. Next, we demodulate the FM “audio” into individual waveforms. We then estimate the various instrument constants through careful measurement of “weight-lift” tests performed prior to each UGT on each instrument. Finally, these coefficients allow us to scale and shape the derived instrument response of the seismographs and compute poles and zeros. The result of this process is a digital record of the recorded seismic ground motion in a modern data format, stored in a searchable database. To date, we have digitized tapes from 592 UGTs.

Larry Johns, Esquire’s impressive career as a lawyer propelled his involvement in numerous legal battles that centered on exposure to environmental harms. Here, Dr. Stephanie Malin interviews Larry Johns to discuss the accidental Baneberry venting disaster during that underground nuclear test, the subsequent Baneberry legal case and outcomes that ensued, and legacies of nuclear contamination and environmental injustice. The interview focuses on Larry’s twenty-five year battle for justice for two workers impacted by the botched detonation of the Baneberry nuclear test, and what this signifies for other people and communities with their own nuclear legacies. Larry reflects on institutional barriers that limit people’s abilities to access useful and accurate information regarding safety and health risks and the ways that federal denial of negligence – as well as a refusal to acknowledge links between workers’ cancers and exposure to fallout – ultimately shaped the outcomes of this case. This interview reminds us of the important ways that institutions shape environmental risks and (in)equality and how these institutions can be even more accountable for and effective in protecting public health and the environment.

— The correlation between lithospheric earthquakes on the American continent and tropical cyclones that arose after the French nuclear tests is considered. The transfer of the local impact of TC on the lithospheric plates of the other hemisphere is proposed to be assessed by the effect of "Fantom" TC symmetric with respect to the center of the Earth. It is shown that the localization of earthquakes shifts in accordance with the movement of the "Fantom" TC and its intensity. This indicates that TCs are a trigger for earthquakes in the most intense seismic areas.

Harnessing atomic particles and radiation led to powerful and world changing technologies. The field of medical imaging has saved countless lives and continues to push the boundaries of medical interventions and research, which would have been impossible without the first x-ray machines. Unfortunately, not all inventions have been so altruistic. The advent of nuclear weapons showed the world the destructive potential possible via scientific inquiry. While the dangerous effects of radiation exposure were documented from the inception of this technology, catastrophic events like the bombing of Hiroshima and Nagasaki and nuclear disasters at Chernobyl Semipalatinsk or Fukushima provide a real-time glimpse into the long-term effects of exposure. Investigating the causes of this exposure in order to prevent future accidents is essential, but so too is cataloguing the rates and types of exposure among the victims. With this information correlations between exposure and health effects, both short- and long-term can be interrogated. This data is crucial for the understanding of the mechanisms behind radiations effects on living creatures and in assessing risks, safety protocols and treatment. Dr Masaharu Hoshi, Professor Emeritus at the Hiroshima University, has spent most of his career travelling around the world, visiting the sites of nuclear disasters in an effort to fully comprehend the risks. He is now using case studies to investigate the radiation exposure and health effects of the residents of radioactive microparticles.

Purpose: To analyze the effects of DNA repair polymorphism and other factors on the frequency chromosome aberrations in an irradiated cohort of subjects living around the Semipalatinsk nuclear test...

The US nuclear-policy community did not always accept today’s conventional wisdom that a state’s first nuclear test is a critical milestone; that even a small, rudimentary nuclear arsenal is a majo...

Lee Waisler, Bomb Cage, 1981, hexagonal wood cage and disarmed World War II bombs (artwork © Lee Waisler; photograph provided by Archives of American Art)Press conference with sculpture unveiling f...

SUMMARYNorth Korea conducted sixth underground nuclear test on 3 September 2017. Unlike its previous tests, a rare subsequent collapse event occurred after about 8.5 min. As two types of distinctive shallow seismic events, accurate inversion of their focal mechanisms is important for event identification for CTBT. In this paper, we carry out moment tensor inversion of the nuclear test and the collapse event with gCAP using waveform data from dense regional seismic stations. And their focal mechanisms are further constrained with surface wave amplitude ratio. The results show that the surface wave amplitude ratio has further constraints for screening the waveform inversion results. The resolution of the focal mechanism inversion for the nuclear test is high, which is close to a Crack source. However, the resolution for the collapse event inversion is not so high and the source type is difficult to be accurately determined. One reason of the poor resolution for the collapse event may be due to the limited availability of high quality data, and complexity of the source process might be another factor.

SUMMARY The Democratic People's Republic of Korea (North Korea) conducted its sixth and largest affirmed underground nuclear test on 2017 September 3. Analysis of Interferometric Synthetic Aperture Radar (InSAR) data revealed detailed surface displacements associated with the nuclear explosion. The nuclear explosion produced large-scale surface deformation causing decorrelation of the InSAR data directly above the test site, Mt. Mantap, while the flanks of the Mountain experienced displacements up to 0.5 m along the Line-of-Sight of the Satellite. We determined source parameters of the explosion using the Bayesian inversion of the InSAR data. The explosive yield was estimated as 245–271 kiloton (kt) of TNT, while the previous yield estimations range from 70–400 kt. We determined the nuclear source at a depth of 542 ± 30 m below Mt. Mantap (129.0769°E, 41.0324°N). We demonstrated that the Bayesian modelling of the InSAR data reduces the uncertainties in the source parameters of the nuclear test, particularly the yield and source depth that are otherwise poorly resolved in seismic methods.

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) prohibits the testing of all nuclear weapons, no matter how small. Although the CTBT is not yet in force, its verification is supported by the International Monitoring System (IMS), which is about 90% complete. Using IMS data, seismologists are able to detect well-coupled underground nuclear explosions with yields larger than ∼0.5–1 kt anywhere in the world with high confidence. Lowering the detection threshold significantly, say to yields of 10−4–10−1 kt fully coupled, will require augmenting IMS data with records from thousands of seismometers that are deployed in various regional, national, and global networks. It will also require routine analysis (detection, location, and characterization) of small seismic events (M 0–3) that are well recorded only at local distances (

On 3 September 2017 at around 12:30, the Japan Meteorological Agency reported that the seismic waves with an explosive source were detected at around the nuclear test site in the Democratic People's Republic of Korea (DPRK). An explosion signal, cavity collapse signal, and T-wave were observed in the Japanese seismic network. We carried out a long-period seismic waveform inversion to explain the source mechanisms of the explosion and collapse. We also used a finite difference method (FDM) simulation to explain the propagation mechanism of the T-phase.

The article presents the analysis of a documentary array on Semipalatinsk nuclear test site using analytical services of the Web of Science database. It identifies the authors, organisations, countries, leading in the publications number at the research field. Shows the journals in which articles on the studied problem are published most frequently. Enumerates scientific meetings where the problems of Semipalatinsk test site were discussed and identifies the most cited publications. Using CiteSpace software, the paper reveals and visualises research fronts and its intellectual bases by means clustering and cluster automated labelling of Semipalatinsk test site papers co-citation network. Document co-citation network and research clusters are revealed using CiteSpace software. It shows, that studies are related to research of medical and biological (genetic changes, diseases as a result of ionizing radiation) effects of nuclear tests and its effects on the environmental situation (degree of contamination of the territory); the effectiveness of various dosimetry methods to determine the degree of radiation exposure on living organisms and objects of inanimate nature. The work represents scientometric visualisation of the documentary array showing research trends on Semipalatinsk nuclear test site.

Ultrasonic thermometry has great potential to improve temperature measurements in irradiation experiments performed in nuclear test reactors. The flexibility of the measurement makes it applicable to a wide range of potential test conditions, in terms of temperature, radiation, and chemical environment. However, the range of several typical ultrasonic thermometer configurations are not well defined. The research described in this document attempts to define an operational envelop for multiple configurations and sensor materials.

This chapter traces the history of attempts and achievements in regulating the use of nuclear energy and material, focusing on nuclear non-proliferation and disarmament. Ever since its invention, the nuclear weapon has occupied a special place in the global security order, both militarily and politically, due to its extraordinary destructive power. This picture is further complicated by the fact that nuclear material has both military and civilian uses. Civilian use of nuclear material includes generating electricity through nuclear reactors. Nuclear material also has medical, agricultural, and other peaceful applications, such as its use in the treatment of cancer. The chapter assesses in detail such treaties as the Partial Test Ban Treaty, the Treaty on the Non-Proliferation of Nuclear Weapons, the Comprehensive Nuclear-Test-Ban Treaty, and the Treaty on the Prohibition of Nuclear Weapons. It also looks at the current challenges involving the Democratic People’s Republic of Korea and Iran.

Sentinel-1A/B radar remote sensing data were applied for the first time to determine the sixth nuclear test, its underground explosion h-bomb location and affected zone in North Korea, on September 3, 2017. Location of epicenters nuclear test were found according to line-of-sight displacement images via its maximum value. Line-of-sight displacement images were obtained by processing in the GMTSAR package in the VirtualBox virtual machine of the Linux Ubuntu 16.04 operation system. In this research, three scenes Sentinel-B data with descending orbits were considered, one after and two before the event (the nuclear test date) scene were used.

After North Korea’s fourth nuclear tested in January 2016, U.S. and South Korea has an official discussion started in early February 2016. The choice to deploy the anti-missile defense system THAAD was made in July 2016 and therefore the first launchers in May 2017. This launch was in line with the tenure of President Moon Jae In at that point. President Moon Jae In initially opposed THAAD but has now accelerated its deployment in response to North Korea’s nuclear test on September 3. Even before the official THAAD discussion started, Beijing expressed its opposition to the system. Although China is additionally against North Korea’s nuclear development, THAAD is seen as an arrange to undermine China’s strategic interests within the region. And because of this, China giving a ‘punishment’ to South Korea. This research aims to describe how the conflict between South Korea and Chinese can happen, the impact of the place THAAD in South Korea to the relations between two countries, and the way the conflict ended. This research uses neorealism as an approach. The methodology employing a qualitative method and collecting the data employing Historical-comparative research.

Introduction: The article analyzes the results of 75 years of nuclear tests. The purpose of the work is to provide an economic assessment of the nuclear test damage to the environment.

— The paper investigates the relationship between the development of typhoons and strong earthquakes after the France nuclear tests (NT) in November 1990. It is shown that after the NT acoustic impact on the tropical disturbance of the Pacific Ocean cloud structures self-organized into a system of three interacting category 5 typhoons. The dependence of the earthquakes M> 4.6 and the intensity of these typhoons as well as Typhoon Mike which passed earlier through the Philippine Islands are considered. Areas were found where the impact of typhoons led to earthquakes M> 5.4 of small lithospheric plates.

Radioxenon activity concentrations are monitored globally using the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation, improving the monitoring community's ability to detect radionuclide signatures from an underground nuclear test (UNT). An IMS-like noble gas system is in operation at AWE (Aldermaston, UK) and can collect and measure radioxenon isotopes in environmental air samples. When operated in this mode, data produced is analysed at the UK National Data Centre (NDC) and significant detection events are flagged for further investigation. This work discusses a number of significant detection events analysed using the operational system deployed at the UK NDC, which includes atmospheric transport simulations and a real-time stack-monitoring data feed from the nearest medical isotope production facility in Belgium. A comparison of the expected radionuclide contributions with measured detections is presented, including a comparison of the isotopic ratios for the radioxenon isotopes of interest (133Xe, 131mXe, 133mXe, 135Xe).

Large areas of the former British nuclear test site at Maralinga were contaminated by the explosive dispersal of plutonium. The Australian Government, in consultation with stakeholders, determined that the site should be cleaned-up so that it is fit for unrestricted habitation by the Aboriginal traditional owners (Maralinga Tjarutja). Engagement with the stakeholders, particularly the Maralinga Tjarutja, determined that the specific criterion for rehabilitation was 5 mSv y−1 and that some restrictions on permanent occupancy should remain. Remediation of the site began in 1995, took 5 years and cost AU$106 million. The site was returned to its traditional owners in 2009 and is now the site of a flourishing tourism operation.

The artificial earthquake of mb 6.1 related to the North Korea’s sixth nuclear test occured at Mt. Mantap, North Korea on September 3, 2017. It was reported that a large and complex surface deformation was caused by the event. The surface deformation was composed of expansion of explosions, collapse, compaction and landslides. Since the precise vertical deformation measurement is very important to estimate the stability of the nuclear test facility, we retrieved a precise 3D surface deformation field and then decomposed the vertical deformation pattern from the 3D deformation. The measured maximum deformation was about − 491, − 343 and 166 cm with the measurement uncertainty of about 3.3, 4.1 and 2.7 cm in the east, north and up directions, respectively. The maximum horizontal deformation was approximately 515 cm. The horizontal deformation clearly showed a radial pattern because it was mainly caused by the explosions and landslides, while the vertical deformation displayed a rugged pattern because it was affected by the explosions, compaction and collapse. The collapse may seem to occur along the underground tunnels and at the test site’s epicenter as well. Moreover, the severe collapse was observed westside from the epicenter of the sixth nuclear test, and it has a depth of about 68.6 cm on the area of 0.3765 km2. On the basis of our results including the shapes, locations and volume changes of the large collapse, evidently a new vital piece of information was obtained so that it could be used to interprete the sixth nuclear test more accurately.