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Leonard Campanello (Ph.D. ’20, physics) spent the last three years on an ambitious mission—helping billions of Google Maps users find exactly what they’re looking for.

“I worked on the search function for Google Maps: you move the screen to a section of the map where you want to look for restaurants or hotels or things to do, add filters or attributes, like it has to be dog friendly or have a waterfront view,” Campanello explained. “And you want Google Maps to give you the best answer every time.”

As a Senior Data Scientist at Google, Campanello’s work brought science to the search process, applying the interdisciplinary physics training he received as a Ph.D. student in Professor Wolfgang Losert’s lab at the University of Maryland. Working on the Google Maps team, Campanello put his experience with models, algorithms, and analytics to work to better understand Maps users and optimize their search results.

“So, when you first issue a search, there's a list of places in a particular order. That order is carefully controlled,” Campanello explained. “We’ve proven that changing ranking algorithm has a material impact on the user's experience, and, at the end of the day, we need to know, did we have a net positive or a net negative effect on users? And we always strive to go in the net positive direction.”

As a scientist, Campanello has always been passionate about finding the stories hidden in data and building statistical models that capture the essence of the data, putting his physics skill set to work to answer a question or solve a problem.

“At the core of many problems in both physics and data science, I think we are trying to understand the data generating process so that we can better explain the fundamental physical phenomena driving what we see,” Campanello explained. “We observe that applying a force results in some change in a measurable quantity, whether the subject is a Google Maps user or a cell under the microscope. What's going on in the background that's fundamentally causing that change? How can we use this information to better understand our world? That’s what we want to find out.”

All in on physics

Campanello was a strong student who went all in on science and math since high school and earned a bachelor’s degree in physics from St. John’s University in 2013. Then, still unsure about how physics would translate into a future career, Campanello decided to pursue his Ph.D. at UMD, where he would have access to various options.

“I didn't know that what I wanted to do with enough certainty that I could commit to a graduate school that was kind of one dimensional,” Campanello recalled. “UMD had a massive physics department with a diversity of people in experiment and theory, whether it was condensed matter or high energy or biophysics or whatever, and that range of options was what ultimately kind of pulled me to UMD.”

After spending his first year working in condensed matter theory, a class with Physics Professor Michelle Girvan gave Campanello a whole new perspective.

“The class was nonlinear dynamics of extended systems and to this day it's probably the most influential class I ever took,” Campanello said. “Her problem-solving approach, including using graph theory and complex systems models, which I was never exposed to before, was eye-opening. We could actually create mathematical representations of all of these phenomena that we see in the world. And I was just wowed.”

At Girvan’s suggestion, Campanello joined Losert’s lab and began his Ph.D. research quantifying and modeling different dynamic processes, specifically complex interactions in biological systems.

“We already knew what some of the interactions were, so we knew that if we put this immune cell in the presence of some material, the immune cell would react in a specific way, which we could also measure under a microscope,” Campanello explained. “So given this set of biochemical information on the way these things behave short-term, medium-term and long-term, we said, how can we fit mathematical models to the microscope data and then use this to make inferences about this system as a whole?”

Opportunities, collaborations and simulations

Campanello took advantage of many opportunities at UMD, from teaching multiple MATLAB Boot Camps on image processing, computer vision and data analysis to coaching teams of data science students for the annual university-wide Data Challenge competition. Meanwhile, his continuing work in Losert’s lab exposed him to a world of possibilities.

“Wolfgang gave me and everyone in his lab the opportunity to work on so many different projects and collaborations with the National Institutes of Health and others, whether it was fundamental cell biology to projects on the interface of immunotherapies and autoimmune diseases to cancer, it's just crazy how much exposure we had,” Campanello noted. “He would help us identify opportunities to apply our analysis and modeling tools, give us guidance on the projects, and then let us to run with it. I really appreciated that.”

Campanello earned his Ph.D. in August 2020 and continued to do research at UMD for about six months before landing a job at Citibank in early 2021, applying his experience in modeling and analytics to consumer banking. 

Later that same year, he accepted a very different kind of opportunity at Google, working with the team that supports Google Maps to evaluate, advance and improve its ever-expanding search functions and, later, new capabilities, thanks to the addition of artificial intelligence.  

“The team is like 30 or so engineers, product managers, designers, user-experience researchers, and I was the one data scientist,” Campanello explained. “One of my primary responsibilities when I first joined was to create metrics or measurements that were absolute—meaning not open to interpretation—and I spent a lot of time doing research in that area to ensure that those measurements aligned with what we wanted for the user. What do we measure to know if we made the experience better?”

A new opportunity

In February 2025, after more than three years at Google, Campanello left to join Optiver, an Amsterdam-based global market maker that buys and sells securities to provide liquidity to markets. In this new position, he’ll again leverage his physics skill set, this time as a quantitative researcher.

“Part of my role will be to help improve the team's predictions in order to make better trading decisions. Can we make predictions right now about what will happen later today or later this hour or even just one minute from now?” Campanello explained. “If we can put numbers to these things and build models that accurately predict outcomes, then we can ultimately use those models to improve liquidity for all market participants.”

Fascinated by finance—and still inspired by the power of physics—Campanello looks forward to this next opportunity to grow.

“I've always had an interest in finance and what I'm looking forward to the most in this new role is the ability to really further my skill set,” Campanello said. “I want to get more exposure to what's happening at the bleeding edge of modeling and data science in quantitative finance. And I think this will be a good avenue for me to do that.”

Written by Leslie Miller

IceCube Search for Extremely High-energy Neutrinos Contributes to Understanding of Cosmic Rays

Neutrinos are chargeless, weakly interacting particles that are able to travel undeflected through the cosmos. The IceCube Neutrino Observatory at the South Pole searches for the sources of these astrophysical neutrinos in order to understand the origin of high-energy particles called cosmic rays and, therefore, how the universe works. 

IceCube has already shown that neutrinos can exist up to about 10 PeV in energy, but both experimental and theoretical evidence suggests extremely high-energy (EHE) neutrinos should reach higher energies. One component, called cosmogenic neutrinos, are expected to be produced when the highest energy cosmic rays interact with the cosmic microwave background. These EHE neutrinos would have an astounding one joule of energy per particle, or higher.

By understanding the properties of cosmogenic neutrinos, such as their quantity and distribution in energy, scientists are hoping to solve the 100-year-old mystery of the origin of ultra-high-energy cosmic rays (UHECRs), with energies exceeding 1 EeV. In a study submitted to Physical Review Letters, the IceCube Collaboration presents a search for EHE neutrinos using 12.6 years of IceCube data. The nondetection of neutrinos with energies well above 10 PeV improves the upper limit on the allowed EHE neutrino flux by a factor of two, the most stringent limit to date. The collaborators also used the neutrino data to probe UHECRs directly. This analysis is the first result using neutrino data to disfavor the hypothesis that UHECRs are composed only of protons.

This figure shows the neutrino landscape at the highest energies between a few PeV and 100 EeV (1020 eV). The red line shows the flux limit we set due to not observing any neutrinos with extremely high energies. It is compared to the previous IceCube result using 9 years of data and to a measurement made by the Auger collaboration. Models of the extremely high-energy neutrino flux are shown in grey (cosmogenic neutrinos) and light blue (neutrinos from AGN), which we can also constrain with our analysis. Credit: IceCube CollaborationThis figure shows the neutrino landscape at the highest energies between a few PeV and 100 EeV (1020 eV). The red line shows the flux limit we set due to not observing any neutrinos with extremely high energies. It is compared to the previous IceCube result using 9 years of data and to a measurement made by the Auger collaboration. Models of the extremely high-energy neutrino flux are shown in grey (cosmogenic neutrinos) and light blue (neutrinos from AGN), which we can also constrain with our analysis. Credit: IceCube CollaborationIn the search for EHE neutrinos, researchers looked for neutrino “events” where neutrinos deposited a huge amount of light inside the detector. However, because most high-energy neutrinos are absorbed by the Earth, the focus of the study shifted to neutrinos arriving sideways at (horizontal) or above (downgoing) IceCube. Focusing on horizontal events in particular also allowed the researchers to eliminate most of the overwhelming background of atmospheric muons caused by cosmic-ray interactions above IceCube in the atmosphere.

 Using a novel method developed by Maximilian Meier, an assistant professor at Chiba University in Japan and colead on the study, they were able to identify how “clumpy” or stochastic an event was, which was helpful because true neutrino events are more stochastic than the cosmic-ray background.

“The non-observation of cosmogenic neutrinos tells us, under some pretty conservative modeling assumptions, that the cosmic-ray flux is mostly composed of elements heavier than protons,” says Brian Clark, an assistant professor at the University of Maryland and colead on the study. “This is a big open question and something scientists have been trying to answer for almost one hundred years.” 

Clark adds that the two other large-scale particle astrophysics experiments—the Pierre Auger Observatory and the Telescope Array—have been trying to answer the same question for almost a decade. Because they measure the cosmic-ray air showers directly, interpreting the data relies on sophisticated modeling of the nuclear physics of cosmic-ray interactions. This is where IceCube offers a complementary approach that, as described in the paper, is largely insensitive to those modeling uncertainties. This makes it an important, independent confirmation of the results obtained by air shower experiments. Brian ClarkBrian ClarkMaximilian MeierMaximilian Meier

“This is the first time a neutrino telescope has managed to do this. And it was a major promise of the discipline, so it’s very exciting to see it happen,” says Clark. 

Future studies by the IceCube Collaboration will look to machine learning in order to extract the most out of the IceCube data. 

“We are really excited to see the next generation of detectors, like IceCube-Gen2, come online, which will be ten times larger than IceCube and, therefore, significantly increase our capabilities to detect cosmogenic neutrinos in the future,” says Meier.

+ info “A search for extremely-high-energy neutrinos and first constraints on the ultra-high-energy cosmic-ray proton fraction with IceCube,” IceCube Collaboration: R. Abbasi et al. Submitted to Physical Review Letters. arxiv.org/abs/2502.01963

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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