Kiyong Kim Elected as a Fellow of Optica

Kiyong Kim has been selected as a 2025 Optica Fellow for his pioneering contributions to the generation and understanding of terahertz radiation from strong laser field interactions with matter.  He is one of 121 members, from 27 countries, selected for their significant contributions to the advancement of optics and photonics through education, research, engineering, business leadership and sKiyong KimKiyong Kimervice.

Kim received his B.S. from Korea University and his Ph.D. from the University of Maryland. His graduate research focused on measuring ultrafast dynamics in the interaction of intense laser pulses with gases, atomic clusters, and plasmas. This work earned him the Marshall N. Rosenbluth Outstanding Doctoral Thesis Award from the American Physical Society.

Following his doctoral studies, Kim moved to Los Alamos National Laboratory as a Director’s Postdoctoral Fellow and while there received a Distinguished Performance Award. After accepting a position as an Assistant Professor at the University of Maryland in 2008, he received a DOE Early Career Research Award and an NSF Faculty Early Career Development Award. Kim also received the departmental Richard A. Ferrell Distinguished Faculty Fellowship in 2014.

From 2021 to 2022, Kim held appointments at Gwangju Institute of Science and Technology (GIST) and the Center for Relativistic Laser Science (CoReLS) at the Korean Institute for Basic Science, leading experiments on petawatt laser-driven electron acceleration, nonlinear Compton scattering of petawatt laser pulses and GeV electrons, and high-power terahertz generation.

With colleagues in physics and the Institute for Research in Electronics & Applied Physics (IREAP), he is co-PI on a $1.61M Major Research Instrumentation (MRI) award from the National Science Foundation (NSF) to upgrade high-power laser systems at UMD.

 

From Space Science to Science Fiction

From her earliest years, Adeena Mignogna (B.S. ’97, physics; B.S. ’97, astronomy) always saw space in her future. It started with “Star Wars.”

“I have memories of watching the first ‘Star Wars’ movie with R2-D2 and C-3PO when I was about 6 years old and I really connected with the robots, wanting to know how we make this a reality,” she recalled. “For a while, I thought I was going to grow up and have my own company that would make humanoid robots, but the twist was, we were going to live and work on the moon. I could even picture my corner office and the view of the moon out the window.”Adeena Mignogna Adeena Mignogna

For Mignogna, that boundless imagination and her childhood fascination with space and science launched two successful and very different careers—one in aerospace as a mission architect at Northrop Grumman, developing software and systems for satellites, and the other as a science fiction writer, spinning stories of robots, androids and galactic adventures in her many popular books. For Mignogna, space science and science fiction turned out to be a perfect combination. 

“I think of it as kind of like a circular thing—science fiction feeds our imagination, which possibly inspires us to do things in science. And science feeds the science fiction,” Mignogna explained. “Working in the space industry is something that I always wanted to do, and I always wanted to write as well, so I’m glad that I'm really doing it.”

Drawn to science

The daughter of an engineer, Mignogna was always drawn to science and technology.

“I am my father's daughter,” she said. “My dad brought home computers, and I learned to program in BASIC, so it was kind of always obvious that I was always going to do something STEM-ish.” 

Inspired by the real-life missions of NASA’s space shuttle and the Magellan deep space probe and popular space dramas like “Star Wars” and “Star Trek,” Mignogna’s interest in aerospace blossomed into a full-on career plan. As she prepared to start college at the University of Maryland in the early ’90s, she began steering toward two majors.

“At first, I thought maybe I'm going to major in astronomy because I loved space and space exploration,” Mignogna recalled. “But my high school physics teacher had degrees in physics, and he had done a lot of different things. He had worked at Grumman during the Apollo era, he had done astronomy work, and so I was like, ‘Okay, if I major in physics, I could do space stuff, I could do anything.’ So in the end, I majored in both.”

Surprisingly—at least to her—at UMD, Mignogna discovered she loved physics.

“What do I love about physics? It's very fundamental to how everything works,” she explained. “I used to tease my friends in college who majored in other sciences that at the end of the day, they were all just studying other branches of physics—like math is just the tool we use to describe physics and chemistry is an offshoot of atomic physics and thermodynamics. And even though I was making fun, I do probably think there's some truth to that, and that might be why I like physics so much.”

Hands-on with satellites

By her sophomore year, Mignogna got her first hands-on experience with aerospace technology.  

“I wound up getting a job in the Space Physics Group, and they built instrumentation for satellites,” Mignogna explained. “I happened to learn about this at the right time when they were looking for students for a new mission, and I worked on that mission from day one till we turned the instrument over to [NASA’s] Goddard Space Flight Center, which was very cool.”

Working in that very hands-on lab assembling and sometimes reassembling science instruments that would eventually fly in space, Mignogna realized she was on the right path. 

“I was touching spaceflight hardware. I was touching stuff that was going into space,” she recalled. “It was really exciting.”

For Mignogna, working side by side with space scientists at UMD and getting hands-on training in skills like CAD drafting gave her the tools she needed to land her first job at NASA’s Goddard Space Flight Center.

Mignogna eventually landed at Orbital Sciences Corporation, which later became part of Northrop Grumman. For the next 16 years—earning her master’s degree in computer science from the Georgia Institute of Technology along the way—she expanded her space software and systems expertise and became a leader in Northrop’s satellite engineering program.

“On the software side, I worked on our command and control software. We have a software suite that controls the satellites, and what I loved was that it gave me exposure and insight into so many different kinds of satellites,” Mignogna said. “With systems engineering, I’m able to go through what we call the full life cycle of the mission. When NASA says, ‘Hey, we need a satellite that's going to do X, Y, Z,’ as a systems engineer, we’re the ones who break that down, and I’m kind of the end-to-end broader picture person in that process. The group that I'm closely associated with today is responsible for Cygnus, which is one of the resupply capsules to the International Space Station.”

From science to science fiction

Over the years, as Mignogna’s career reached new heights so did her work as a science fiction writer, a creative effort that started when she was in high school.

“My dad was a fan of Isaac Asimov and Robert Heinlein, so I knew they were engineers and scientists who also wrote science fiction, and that was something I always wanted to do,” Mignogna said. “At first, I didn't think I could write novels, I thought I could only do short stories. But around 2009, I figured out I could, and I’ve been doing it ever since.”

With titles like “Crazy Foolish Robots” and “Robots, Robots Everywhere,” Mignogna’s Robot Galaxy Series combines science fiction with humor, philosophy and, of course, robots. Her latest book “Lunar Logic” is set on the moon, 100 years from now.

“There are humanoid robots, built and manufactured on the moon, and they live on the moon. And they don't know anything about humans or why they're there,” Mignogna explained. “And then little things happen and they start to question what's going on and why they're there and eventually they kind of figure it all out.”

In Mignogna’s sci-fi worlds, the only limit is her own imagination, which is exactly what makes her work as a writer so enjoyable. 

“In my science fiction work, it’s my way or the highway,” she said. “I can write whatever I want, and I can make it however I want, and there's some satisfaction in that.”

For Mignogna, writing science fiction also provides an opportunity to advance another mission—to get more people interested and excited about science. In regular appearances at sci-fi conferences and other gatherings, Mignogna shares her passion for STEM, hoping to inspire the next generation of scientists—and everyone else.

“All this technology we have today comes from generations upon generations of fundamental science, technology, engineering, mathematics,” she explained, “so if we're going to do more things, we need people to go into these fields. “

As someone who’s always seen the importance of science in her own life, it’s a message she’s committed to sharing.

“You don't have to understand everything about science, but you can appreciate it,” Mignogna noted. “My hope is maybe if I can just connect with a few people indirectly or directly, I can make a difference.” 

 

Written by Leslie Miller

Finding the Beauty in Physics

Phoebe Hamilton’s (M.S. ’11, Ph.D. ’13, physics) research career at the University of Maryland could have ended when she earned her Ph.D. Instead, it marked the start of an exciting challenge—for Hamilton and her fellow high-energy physics researchers in UMD’s Department of Physics.
Phoebe Hamilton, Elizabeth Kowalczyk and Othello Gomes check a photodetector.Phoebe Hamilton, Elizabeth Kowalczyk and Othello Gomes check a photodetector.In fall 2012, Distinguished University Professor and Gus T. Zorn Professor Hassan Jawahery eyed a new opportunity after his research group wrapped up with BaBar, a collider experiment in California.

“BaBar had finished collecting new data and we were looking for the next gig for the group,” Hamilton recalled. “Hassan was my Ph.D. advisor and we talked about how exciting it would be to move to the Large Hadron Collider beauty—LHCb—experiment.”

Just two months before Hamilton defended her dissertation, Jawahery’s group learned that they had been formally accepted into the LHCb experiment, which is named after its primary research subject: a particle called the beauty quark, also known as a bottom quark or b quark. By studying bottom quarks produced by proton-proton collisions at the Large Hadron Collider located near Geneva, Switzerland, researchers hope to come closer to understanding why there is so much matter but so little antimatter in the universe.

Excited by the opportunity to discover new physics at the world’s most powerful particle accelerator, Hamilton stayed at UMD. As a postdoctoral researcher from 2012 to 2020 and a faculty specialist from 2020 to 2023, she developed tools that enabled the LHCb to take measurements previously thought “impossible” by some scientists.

Now, as an assistant professor of physics, her contributions continue to level up the LHCb’s abilities, improving its chances of making groundbreaking findings.

“Getting to stay a postdoc as long as I did at Maryland was a real blessing,” Hamilton said. “I wasn’t sure I’d actually have the chance to become an assistant professor, but I'm very happy to get to do it. Maryland is such a home and such a family to me.”

Raising the BaBar

Hamilton’s interest in physics began in high school and she nurtured it with books about string theory by physicist Brian Greene. After graduating, she enrolled at Youngstown State University to pursue computer science, another one of her interests, but switched to physics after realizing that it inspired and challenged her more than any other subject.

“I like knowing how things work,” said Hamilton, who also enjoys learning new musical instruments for similar reasons. “The fact that physics is orderly and follows these predictable rules has always been fascinating to me.”

Hamilton quickly took to particle physics, and after earning her bachelor’s degree in 2007, she decided to pursue particle theory research in UMD’s graduate program. She chose UMD because of its wide range of research possibilities, which allowed her to try out different specializations before committing.

“I thought I knew what I wanted to do, but there was doubt,” she said. “With UMD, I thought to myself, ‘This is where I’m going to be able to thrive no matter what I do.’”

Hamilton soon discovered she enjoyed the experimental side of particle physics much more than theory. So when Associate Professor Doug Roberts put up flyers seeking student researchers for the BaBar experiment, Hamilton jumped at the chance.

BaBar was Hamilton’s introduction to experimental studies of CP violation, which occurs when two conservation laws of particle physics—charge conjugation and parity—are broken. By measuring CP violation at experiments like BaBar, researchers can begin to understand the differences between matter and antimatter.

“I fell in love with it very quickly,” Hamilton said of BaBar. “It was a fantastic machine and a fantastic experiment.”

Hamilton’s research contributed to the first measurement of how Bs mesons, a family of subatomic particles called mesons that contain a bottom quark and a strange antiquark, are produced at different collision energies. Ultimately, the BaBar experiment shed light on how antimatter is produced and set the stage for Hamilton’s participation in an even bigger—but messier—collider.

“The beautiful thing at BaBar was that you would get two hadrons containing bottom quarks and nothing else, so it was very clean and very easy to measure what was going on,” Hamilton said. “Here [at the LHCb], colliding protons is like colliding handfuls of rock salt. You get 100 reconstructed particles in every event and you have to sort through it.”

Achieving the ‘impossible’

For the last 12 years, Hamilton has been working to make those messy collisions a little easier to interpret. UMD’s contribution to the LHCb experiment falls within the realm of lepton flavor universality: a physics principle stating that the only difference between different “flavors,” or types, of leptons—including electrons, muons and tau leptons—is their mass. 

The LHCb is a good fit for this type of research because it analyzes a large number of particles containing b quarks, which transform, or decay, into leptons. In the beginning, though, some scientists thought that lepton flavor universality couldn’t be done at the LHCb because either one or three neutrinos escape undetected during collisions, making it difficult to determine all of the energies and momenta needed to distinguish muons from tau leptons. 

“Because of the messy nature of these proton-proton collisions, the consensus was that this was too hard for LHCb to do,” Hamilton said. “But Jawahery and I worked together on a technique to make some wild approximations and figure out a way to do it anyway.”

And they did figure out a way. Developed from 2013 to 2015 in collaboration with LHCb researcher Greg Ciezarek, their method of analyzing decays led to measurements of lepton flavor universality between muons and tau leptons that were previously thought impossible. 

“It was interesting to go from ‘This is probably another dead-end’ to ‘Oh, this might actually be worth something’ to ‘This is actually the star of the experiment right now,’” Hamilton said. “This is still an active area of research for us. We extended and superseded the 2015 measurement in 2023 and are working on the next generation of this in the data from the second run of the LHC.”

Cracking the K-pi puzzle

Over the years, Hamilton has also played a key role in making the LHCb’s equipment more durable and better at discerning different particles. She helped develop electronics for the Upstream Tracker sub-detector for the experiment’s first upgrade from 2022 to 2023 and is now testing new photodetectors in her lab. These new detectors would measure the light produced in upgraded modules for the LHCb’s calorimeter, which stops particles as they pass through and enables researchers to measure the energy deposited. 

This planned upgrade to the calorimeter aims to make energy measurements more precise, which can ultimately help researchers determine which particles were produced in a collision event.

“One of the big motivations for upgrading the calorimeter is making some of the granularity smaller so that you can tell different particles apart,” Hamilton explained. “Along with the ability to precisely measure the time different particles arrive, it should in principle be able to cope with five times the collision rate.”

Whether Hamilton is toiling in the lab or analyzing data from the LHCb, she continues to find inspiration in physics’ most puzzling questions. She recently submitted a research proposal to dive deeper into matter-antimatter asymmetries and continues to work on developing new and improved techniques for her research. 

From 2014 to 2015, she and her colleagues at UMD developed a way to study b-hadron decays with only one reconstructed trajectory, meaning that certain key information is missing. She believes this technique can now be applied to a persistent challenge in physics called the K-pi puzzle.

“The K-pi puzzle is the possibility that the Standard Model fails to explain the pattern of matter-antimatter asymmetry in b-hadron decays to two pseudo-stable mesons, pions or kaons—or one of each. The Standard Model predicts specific patterns to their CP asymmetries, which we can use to check the Standard Model’s validity, but theorists need measurements of them all,” Hamilton explained. “Some of these involve two trajectories to reconstruct and identify the b-hadron but many do not, and these tend to be the less understood ones.”

Going forward, Hamilton hopes to make more “impossible measurements”—and perhaps challenge or reshape the Standard Model of physics in the process.

“We have an opportunity to contribute to understanding this puzzle in some of the areas that are fuzziest right now,” Hamilton said, “and I think there's exciting things to be tried there.”

 

Written by Emily Nunez

Faculty, Staff, Student and Alumni Awards & Notes

We proudly recognize members of our community who recently garnered major honors, began new positions and more.

Faculty and Staff 
Students
Alumni
  • Adam Ehrenberg (Ph.D, '24) joined the Institute for Defense Analyses (IDA) as a Research Staff Member.
  • Chad Mitchell (Ph.D., '07) is a physicist at the Accelerator Technology & Applied Physics Division of Lawrence Berkeley National Lab.
  • Luke Sollitt (B.S., '97) is a planetary physicist for NASA.
  • C. V. Vishveshwara (Ph.D., '68) was recalled as Scientist of the Day on March 6, 2025.
Department News 

Malcolm Maas Named 2025-26 Churchill Scholar

University of Maryland senior Malcolm Maas has been awarded a 2025-26 Churchill Scholarship, joining only 15 other science, engineering and mathematics students nationwide in winning the prestigious honor. 

“We could not be prouder of how Malcolm Maas represents the University of Maryland to the world,” said Amitabh Varshney, dean of UMD’s College of Computer, Mathematical, and Natural Sciences. “Malcolm is a phenomenal student researcher who is driven to understand complex world problems like climate change and provide innovative solutions to them.”Malcolm Maas. Photo courtesy of same.Malcolm Maas. Photo courtesy of same.

Maas, who plans to graduate in three years with bachelor’s degrees in atmospheric and oceanic science (AOSC) and physics, will receive full funding to pursue a one-year master’s degree at the University of Cambridge’s Churchill College in the United Kingdom. The scholarship covers full tuition, a competitive stipend, travel costs and the chance to apply for a special research grant. 

Maas plans to pursue a Master of Philosophy degree in mathematics.

“I feel incredibly honored to have received this scholarship, and I’m very grateful to everyone who has supported me on my way here,” Maas said. “I’m excited for the opportunity to explore atmospheric dynamics further and to experience Cambridge next year.”

A total of 127 nominations this year came from 82 participating institutions. Ten UMD students have been nominated in the past seven years—and nine of them have been named Churchill Scholars.

“The University of Maryland’s remarkable success in racking up Churchill Scholarships testifies to the excellence of the research opportunities and mentorship our undergraduates receive,” said Francis DuVinage, director of UMD’s National Scholarships Office. “Malcolm Maas’ record of accomplishment as a third-year senior puts him in a class by himself.”

Since 2022, Maas has been working with AOSC Associate Professor Jonathan Poterjoy on fundamental challenges associated with environmental prediction and validation of atmospheric modeling systems. Specifically, he is quantifying the degree to which commonly used data assimilation methods shift models away from physically plausible solutions due to commonly adopted but incorrect assumptions. Maas presented their work in January 2025 at the American Meteorological Society Annual Meeting.

“Malcolm initiated our research collaboration on his own and I fully expect him to draft a first-author paper that we submit for publication this year,” Poterjoy said. “I feel that Malcolm can succeed in virtually any field, and I am pleased to see that he chose a research career in atmospheric science where his talents can have broad human impact.” 

Maas’ research interests and experiences extend beyond his work with Poterjoy and currently range from weather time scales to climate time scales. 

In summer 2024, Maas interned at the University of Chicago with Geophysical Sciences Professor Tiffany Shaw, where he assessed extreme heat and atmospheric circulation trends associated with Arctic sea ice loss in climate models and observational datasets. He presented this work at the American Geophysical Union’s Annual Meeting in 2024.

In summer 2023, Maas participated in the undergraduate summer intern program at the Lamont-Doherty Earth Observatory and worked on a project with Kostas Tsigaridis, a research scientist at Columbia University and the NASA Goddard Institute for Space Studies. Maas used a large dataset of Earth system model simulations to explore the effects of volcanoes on climate and atmospheric sulfur. He used machine learning to develop a tool that estimates where unidentified historical eruptions happened based on ice core data. Maas presented this work at the European Geosciences Union’s General Assembly in 2024 in Austria.

When Maas arrived at UMD in 2022, he joined a group of AOSC students installing and managing a micronet—a small-scale network of weather sensors—across the university’s campus. Five weather stations now provide minute-by-minute updates on the temperature, wind speed, pressure, dew point and rain rate on campus. Maas helped create the data collection system and user-friendly graphs to visualize the data, which are displayed on the UMD Weather website.

When the university and the Maryland Department of Emergency Management installed their first weather tower as part of the Maryland Mesonet in 2023, they asked Maas to quickly adapt his micronet visualization tools to work with the mesonet data. The 23 towers operational around the state—with more than 70 planned—help to advance localized weather prediction and ensure the safety of Maryland's residents and visitors.

For his Gemstone honors research project, Maas and 10 teammates have been working with UMD Mechanical Engineering Professor Johan Larsson to optimize the shape of marine propellers.

In high school, Maas helped build the first global tornado climatology database. He gathered and processed historical data for over 100,000 tornadoes that occurred around the world. The project’s website raked in 160,000 page views during its first year, and the work was published in the Bulletin of the American Meteorological Society in 2024.

Outside of class, Maas plays the pipe organ, represents the Ellicott Community on the Student Government Association, tutors with the Society of Physics Students and is a member of the Ballooning Club. He received a Barry M. Goldwater Scholarship, National Merit Scholarship, President’s Scholarship and the Department of Physics’ Angelo Bardasis Scholarship.

After his time at the University of Cambridge, Maas plans to pursue a Ph.D. in atmospheric science.