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        • Perspective: Nuclear sleuthsToday, Everyone’s a Nuclear Spy

          There was a time when tracking nuclear threats was the domain of secret agents, specialists at high-powered government intelligence agencies, and think-tank experts. Not anymore. Amy Zegart writes that today, the world of new nuclear sleuths looks like the Star Wars bar scene. What has empowered these nuclear detectives and made their work possible is the fact that in the last 15-20 years, commercial satellites have become common – and their capabilities, although not at the level of spy satellites, are not too far behind. Open-source amateur nuclear sleuthing comes with risks, but Zegart says that despite these risks, the democratization of nuclear-threat intelligence is likely to be a boon to the cause of nonproliferation.

        • Nuclear weaponsHow to Dismantle a Nuclear Bomb: Team Successfully Tests New Method for Verification of Weapons Reduction

          By Peter Dizikes

          How do weapons inspectors verify that a nuclear bomb has been dismantled? An unsettling answer is: They don’t, for the most part. When countries sign arms reduction pacts, they do not typically grant inspectors complete access to their nuclear technologies, for fear of giving away military secrets. Now MIT researchers have successfully tested a new high-tech method that could help inspectors verify the destruction of nuclear weapons. The method uses neutron beams to establish certain facts about the warheads in question — and, crucially, uses an isotopic filter that physically encrypts the information in the measured data.

        • Nuclear forensicsHelping Nuclear Forensics Investigations by Going Small

          Until recently, the analysis and identification of nuclear fuel pellets in nuclear forensics investigations have been mainly focused on macroscopic characteristics, such as fuel pellet dimensions, uranium enrichment and other reactor-specific features. But scientists are going a step further by going down to the microscale to study the diverse characteristics of nuclear fuel pellets that could improve nuclear forensic analysis by determining more effectively where the material came from and how it was made.

        • Nuclear accidentsRussian Nuclear-Monitoring Stations’ Silence Fuel Fears over Extent of Deadly Blast

          Officials at the Vienna-based Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) say that two nuclear monitoring stations in Russia have resumed operations after mysteriously halting the transmission of data. The CTBTO did not comment on August 20 on the other two stations which it previously said had gone silent in the aftermath of an explosion at a Russian naval test site that killed at least five people and caused a temporary spike in radiation levels.

        • Nuclear detectionRemotely Monitoring Nuclear Reactors with Antineutrino Detection

          Technology to measure the flow of subatomic particles known as antineutrinos from nuclear reactors could allow continuous remote monitoring designed to detect fueling changes that might indicate the diversion of nuclear materials. The monitoring could be done from outside the reactor vessel, and the technology may be sensitive enough to detect substitution of a single fuel assembly.

        • Nuclear detectionImproving Security of Nuclear Materials Transportation

          Nuclear power plants can withstand most inclement weather and do not emit harmful greenhouse gases. However, trafficking of the nuclear materials to furnish them with fuel remains a serious issue as security technology continues to be developed. Physicists conducted research to enhance global nuclear security by improving radiation detectors. According to them, improving radiation detectors requires the identification of better sensor materials and the development of smarter algorithms to process detector signals.

        • Perspective: Nuclear wasteTruth and Fearmongering: Yucca Mountain Nuclear Waste Repository

          Is it a good idea to store 77,000 tons of highly radioactive nuclear waste in a repository in Nevada’s Yucca Mountain? Many Nevada politicians say it is a bad idea, but scientists argue that the facts do not support the fears these politicians stoke. These scientists say that Colorado, whose surface rock contains about a billion tons of uranium, should have much more to worry about than Nevada. One scientist says: “If the Yucca Mountain facility were at full capacity and all the waste leaked out of its glass containment immediately and managed to reach groundwater, the danger would still be 20 times less than that currently posed by natural uranium leaching into the Colorado River.”

        • WMD detectionEpigenetic Tool for Detecting Exposure to WMD

          With a $38.8 million award from DARPA, researchers are working on developing a field-deployable, point-of-care device that will determine in 30 minutes or less whether a person has been exposed to weapons of mass destruction or their precursors. The device will be capable of detecting the health effects of a number of substances associated with weapons of mass destruction, including biological agents, radiation, chemicals and explosives. The detection devices will scan potential exposure victims for epigenetic changes, that is, chemical modifications that affect genes, altering their expression while leaving the genetic code intact.

        • Perspective: WMD detectionTrump Administration Has Gutted Programs Aimed at Detecting Weapons of Mass Destruction

          The Trump administration has quietly dismantled or cut back multiple programs that were created after the Sept. 11, 2001, attacks to help detect and prevent terrorism involving weapons of mass destruction, a Times investigation has found. The retreat has taken place over the last two years at the Department of Homeland Security, which has primary domestic responsibility for helping authorities identify and block potential chemical, biological, radiological and nuclear threats. A Los Angeles Times investigation found that the changes, not previously reported, were made without rigorous review of potential security vulnerabilities, the Times found, undermining government-wide efforts aimed at countering terrorist attacks involving unconventional weapons, known as weapons of mass destruction.

        • Radiation risksHelping first responders deal with dirty bombs

          If a radiological dispersal device (RDD), or “dirty bomb,” ever explodes in the United States, emergency crews may be better prepared because researchers have developed a new simulator, which show first responders what an optimal response to an RDD would look like.

        • First respondersFirst Responder Radiological Preparedness

          A radiological dispersal device (RDD), or “dirty bomb,” detonation in a local jurisdiction will have significant consequences for public safety, responder health and critical infrastructure operations. First responders and emergency managers must quickly assess the hazard, issue protective action recommendations, triage and treat the injured, and secure the scene in support of the individuals, families and businesses in the impacted community.

        • WMD exposureNew technology to measures WMD threat exposures

          Researchers are looking to find molecular signatures in blood that identify previous exposures and time of exposure to materials that could be associated with weapons of mass destruction (including infectious agents, chemicals, and radiation). The epigenome is biology’s record keeper, and Epigenetic technology will provide a new tool in the fight against the proliferation of weapons of mass destruction.

        • Iran’s nukesIran suspending some nuclear deal commitments

          Iranian President Hassan Rouhani announced Wednesday his country will suspend its compliance with prohibitions on stockpiles of enriched uranium and heavy water that were imposed as part of the 2015 international agreement on its nuclear program.

        • Nuclear proliferationDetecting radioactive material remotely

          Physicists have developed a powerful new method to detect radioactive material. By using an infrared laser beam to induce a phenomenon known as an electron avalanche breakdown near the material, the new technique is able to detect shielded material from a distance. The method improves upon current technologies that require close proximity to the radioactive material.

        • Nuclear wasteEasier access to radioactive waste

          At the Hanford Site, waste retrieval has been completed in 17 of 149 large concrete underground single-shell tanks. The tanks were constructed of carbon steel and reinforced concrete between 1943 and 1964 to store a radioactive mix of sludge and saltcake waste from past nuclear processing activities. Hanford is installing new access holes in the tank domes for future retrieval efforts.

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