By Zach Winn | MIT News Office

Mentorship has played a central role in the twists and turns of Associate Professor Areg Danagoulian’s life.

As a boy, it led him first to mathematics, where a passionate teacher and mentorship from his parents instilled in him a love for the subject. He then followed in the footsteps of his physicist parents and became a physicist himself. During his career, mentorship has helped Danagoulian follow his research interests, from basic to applied nuclear physics and then to industry. More recently, Danagoulian returned to his alma mater, MIT, where he delights in guiding the students in his lab as they become mature scientists.

Joining the Institute’s faculty in 2014 was the latest phase change in a career full of shifting research interests. In that time Danagoulian, who was awarded tenure last year, has developed new technologies for detecting nuclear warhead materials, encrypting their technical details, and verifying their dismantlement.

On the edge of a breakthrough

Danagoulian could not believe his eyes. It was the beginning of 2020, and his lab had just finished running preliminary experiments with collaborators at Princeton University on a new, portable system for detecting fissionable material that could be used in nuclear warheads. The plan had been to gather baseline data and to optimize conditions from there. But as he looked at the early results, he noticed a small but unmistakable blip exactly where one would be if the system were already working.

“The dip was barely visible, but I realized it wasn’t just my eyes,” Danagoulian says. “We had this suboptimal setup and we already had a weak — but real — signal. That really motivated us. We got super excited.”

If the system could work with high enough accuracy, it could transform nuclear disarmament treaties between superpowers. In the past, such treaties have targeted the delivery systems (e.g. missiles and bomber aircraft) of the nuclear weapons rather than the weapons themselves, in part because the technology for verifying nuclear materials was not compact or sensitive enough to be used at nuclear sites. Danagoulian and his collaborators believed they were on the precipice of developing a technology that could change that.

Then the Covid-19 pandemic began. Danagoulian’s lab was temporarily closed, as was the lab at Princeton.

“We’re looking at this plot, and we’re thinking there is a gold mine waiting for us,” Danagoulian says.

After months of analyzing data and planning further experiments, Danagoulian’s lab reopened in June of last year with safety precautions in place.

“We were itching for action. The moment the doors opened, we ran into the lab,” Danagoulian recalls. “We started gathering data — and this time it was really high-quality data due to optimized experimental conditions — and suddenly all these peaks started showing up exactly where they were supposed to. It was this very rewarding thing, this sense of triumph, to do something that had never been done before on such a small scale.”

Since then, Danagoulian has been working with national labs as well as members of the policy community to raise awareness of the technology and learn more about how it could be implemented.

Danagoulian says being at MIT has further exposed him to the field of public policy, helping him build impactful technical solutions and leading to collaborations. He has also developed a related tool for hiding the design details of nuclear warheads during the verification process. That system uses a physics-based analog to common digital encryption methods to scramble data about the weapon’s design. The system addresses another major hurdle to nuclear dismantlement by allowing the international community to inspect a country’s nuclear sites without jeopardizing military secrets.

“Verification of nuclear disarmament is very important, because a treaty without verification is worse than no treaty at all,” Danagoulian says, citing the Comprehensive Test Ban Treaty that was proposed in the 1950s but not fully adopted until 1996, in part because scientists lacked the technology to reliably differentiate underground testing from seismic events.

Supporting others

Amid the multidisciplinary culture of MIT, Danagoulian decided to merge his scientific work with politics. But for his parents, who were both physicists under the Soviet Union (in modern-day Armenia), science and social issues were inseparable.

“In Soviet Armenia, being in a scientist family made you a cultural minority, and it would inevitably become part of your identity,” Danagoulian says. “Here it’s a job, not a social class. But we saw ourselves as a cultural group or a political class. Later, the independence movement in Armenia was largely led by intellectuals and scientists.”

Danagoulian’s family moved to the United States when he was 16. His parents had tough lives as physicists, and while they fostered his love for the sciences, they also encouraged their son to be a computer scientist, which they thought would bring more prosperity and job security. But Danagoulian had discovered a love for physics while preparing for college, and he decided to ignore their pleas. He went on to major in physics at MIT, where he got the chance to work with Professor Richard Milner in the Laboratory of Nuclear Science as part of the Undergraduate Research Opportunities Program (UROP).

Danagoulian completed his PhD work in nuclear physics at the University of Illinois and became a researcher at the Los Alamos National Laboratory. There, he became increasingly interested in applied science and decided to join a Boston-based company developing a cargo scanner for detecting nuclear materials at ports and border crossings around the world.

At sufficiently high energies, photons can pass through even dense structures like steel shipping containers. While working in industry, Danagoulian was trying to develop a system that would send a beam of photons into containers and scan for the subatomic particles that result from collisions with nuclear materials.

Danagoulian and collaborators developed and commercialized the system, which was deployed in the South Boston Container Terminal for two years before being abandoned during the Covid-19 pandemic, largely because of its high price tag. Danagoulian believes it was the first such system deployed in the world and considers it a major technical success. He believes it could be deployed quickly again if needed in a crisis involving nuclear terrorism.

In 2014, Danagoulian returned to MIT to join the faculty of the Department of Nuclear Science and Engineering.

“This department is very collaborative,” Danagoulian says. “Everyone is trying to help you any way they can. It’s a very supportive department, and I think my success is very much associated with the mentorship and advice I’ve gotten.”

Danagoulian has also embraced his role teaching and advising students, although he admits he had to learn to let students handle the research and experiments themselves.

“When I finally got the discipline to let go, it was very rewarding, because I started seeing my students get better, and I started seeing their work becoming better than my own work in that particular area. That was deeply gratifying,” Danagoulian says.

These days, Danagoulian is happy to be in a position to offer the support and guidance that’s played such a central role in his life.

“Most of my choices in life, when it comes to education, research, work, have been heavily influenced by mentorship,” he says. “Mentorship is critically important for shaping you, helping you pick a direction, and encouraging you. I try to help students understand they are capable of doing great things.”

Source: https://news.mit.edu/2022/areg-danagoulian...

Posted
AuthorLaboratory for Nuclear Security & Policy

By Laura Schmidt-Hong | The Tech

As much as nuclear technology and engineering are rooted in physics and radiation, reactors and weaponry, they also involve stories of politics and negotiation, history and diplomacy. The gray decades of the Cold War and today’s evolving landscape of nuclear stability and international relations are inextricable from the technology that drives them. This sort of interdisciplinary symbiosis inspires Scott Kemp’s work in MIT’s Laboratory for Nuclear Security and Policy (LNSP).

A physicist by training, Kemp first became interested in applying politics and history to nuclear science after working in international relations and realizing the need for technical expertise in policy making. Working in the State Department as a science advisor, he noticed that “there’s a tremendous amount of policy, especially in the security space, that just makes no scientific sense whatsoever.” He earned his PhD in Public and International Affairs from Princeton University, where he wrote two dissertation-length analyses: one in history and one in nuclear engineering. The works were “essentially on the same topic, but from two different perspectives,” he said.

Now, as an associate professor of nuclear science and engineering and director of the LNSP, Kemp brings the same interdisciplinary focus to the lab. He works alongside physicists and chemists whose combined expertise enables them to solve problems and develop strategic tools.

Since its inception six years ago, the lab’s research has focused primarily on developing effective methods for treaty verification. Such verification is necessary to ensure that each nation committed to a nuclear treaty truthfully reports the number of warheads in their arsenal. Ensuring accurate self-reporting requires both political and technological approaches.

Inspired by information theory and cryptography, Kemp and Areg Danagoulian ’99, professor of nuclear science and engineering, have developed direct warhead verification protocols that can, in principle, verify the authenticity of a nation’s warheads while maintaining the secrecy of their design. Kemp explained that computers are rather poor tools to carry out such protocols: “all that does is put the burden of confidence on a computer system, and no one can prove that a computer does only what it’s supposed to do and nothing else.” Rather than using computers, they built physical systems that can apply information protection concepts. One such system is a physical implementation of a one-time pad — an encryption technique that involves a single-use key shared between two parties. This method is “the only provably secure form of encryption,” said Kemp, making it uniquely useful for treaty verification. Another system, inspired by zero-knowledge proofs, returns a null result when it compares two identical objects.

The financial stakes of all these efforts are high. According to Kemp, the United States will spend over one trillion dollars over the next three decades revamping their nuclear arsenal. That spending hinges on the United States’s conception of other nations’ nuclear postures and doctrines.

Another necessary element of verification is reconstructing the history of nuclear weapons production programs, particularly secret ones. If one day the United States negotiates a disarmament agreement with North Korea in which it relinquishes its nuclear weapons, Kemp anticipates a new question: how can the United States know how many nuclear weapons North Korea should give up?

Analytical chemistry methods developed by the LNSP may provide the answer. In a collaboration with his colleague Michael Short PhD ’10, professor of nuclear science and engineering, Kemp took advantage of the science behind alpha radiation and its effects on the microstructure of nuclear hardware. Uranium-238, the most abundant isotope of uranium found in nature, and uranium-235, the predominant isotope used in nuclear weaponry, emit alpha particles of different energies when they radioactively decay. As a result, they deposit energy at different depths, in what are known as bragg peaks, inside the materials that make up physical equipment, he said. In turn, scientists can estimate which isotopes of gaseous uranium are present in nuclear machinery by quantifying the radiation damage inside and applying conservation laws.

Kemp noted that this research manifests itself in the lab just like any other research, with one key distinction. “it’s benchwork, and it’s dirty… and it looks like any other lab,” but “it’s been selected to have this particular national security impact.”

Ultimately, through their efforts, Kemp and Short have successfully developed a method to measure structural changes from radiation in the plastic gaskets used in nuclear plants. They are still working to apply the same approach to metal parts, whose chemistry makes them more difficult analytical targets.

The lab and its research have not been immune to recent changes in the politics of nuclear technology and security, however. Kemp had a hand in developing the Iran nuclear deal, through consultations with the State Department and meetings with Iranian officials. When the United States withdrew from the deal and Trump launched a dialogue with North Korea, the LNSP began exploring ways to bring North Korea “into the fold,” Kemp said. In particular, he hopes to develop cooperative opportunities to increase the safety of North Korean reactors, manage its nuclear waste disposal, and use these efforts as a first step in building trust, he said.

Down the road, Kemp envisions the lab similarly extending its focus beyond nuclear security to “any kind of role technology might have” in existential security.

As they begin to explore the security considerations of decarbonization technologies, for instance, energy policy has captured Kemp and the department of nuclear science’s interest. In seeking the “optimal path to decarbonizing the electricity sector,” they hope to determine whether decarbonization technologies create or solve security problems. According to Kemp, vulnerabilities in the United States’ electric grid can be secured with improved planning of how new generation and transmission technologies are deployed.

Through the lab’s current and future work, Kemp ultimately hopes to maintain the interdisciplinary lines of thinking that have always inspired his and the LNSP’s research. “In an era where technology has, in a sense, outpaced our morality,” he said, it is necessary to understand that the “ability to use technology for good or for evil is so powerful that we need institutions and policies to deal with it.”

In the long run, said Kemp, “if you want to use technology to effect positive change in the world, you first need to be equipped with the skills to understand how the world works.”

Source: https://thetech.com/2020/02/27/lnsp-kemp-s...

Posted
AuthorLaboratory for Nuclear Security & Policy