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A student describes her poster at the Vertex 2025 workshop

Vertex 2025 Comes to Rocky Top

When powerful particle beams collide, scientists rely on sophisticated detectors to track the paths of new particles created in the process. UT welcomed a group of those scientists to Vertex 2025, the International Workshop on Vertex Detectors.

The Vertex workshop is an annual forum for physicists and engineers who work in high-energy (elementary particle) and nuclear physics. They meet to share ideas on topics like detector technologies, tracking, electronics, and applications in quantum science and other fields. The focus, as the name implies, is on vertex detectors, whose reach extends beyond that of elementary particle physics.

Tracking Where Particles Start

Professor Stefan Spanier is part of UT’s particle physics group and was part of the meeting’s local organizing committee. He explained the role vertex detectors play, not only in fundamental science, but also in technologies that improve lives.

“When particle beams collide, many new particles are created,” he said. “This happens, for example, every 25 nanoseconds at the Large Hadron Collider (LHC) of CERN near Geneva during its operation. A vertex detector in high-energy physics is a highly accurate instrument designed to track the paths of charged particles immediately after they are produced in a collision. By tracing these paths backward, physicists can determine the origins of the particles, known as vertices.”

“The technology has been adapted for medical imaging, especially in advanced X-ray and nuclear medicine techniques,” he continued. “These detectors offer significant benefits, including high resolution, low radiation exposure, and energy-resolving capabilities.” 

A large group of people standing in front of Ayres Hall on the University of Tennessee, Knoxville, campus

The importance of these instruments drew 68 researchers from Italy, Japan, the United Kingdom, France, Germany, Switzerland, the Czech Republic, and the United States to UT’s campus in mid-August for invited talks by field experts and individual contributions.

Physics Graduate Student Jesse Harris was among the students and postdoctoral associates who presented their work in a poster session held at Knoxville’s iconic Sunsphere.

“One of the highlights for me was presenting my poster,” Harris said. “I had the opportunity to discuss my work with experts in the field, receive valuable feedback, and understand how my research contributes to the broader context of high-energy physics at the Compact Muon Solenoid detector. The conversations I had with other students and researchers were incredibly inspiring. It was a fantastic opportunity to connect with the broader scientific community and build new relationships.”

Spanier said the workshop was valuable because scientists and students discussed vertex detector advances in a classroom-like setting, “while also having opportunities for dialogue and idea exchange outside a formal environment,” including plenty of breaks, social activities, a dinner, and a day of excursions that “helped build stronger relationships and encouraged networking.”

Along with Spanier, the organizing committee comprised three scientists from workshop co-sponsor Oak Ridge National Laboratory (ORNL): Mathieu Benoit, Marcel Demarteau, and Oskar Hartbrich. Spanier was quick to point out that the university’s Conference and Event Services staff was essential to the event’s success.

Harris also helped out with conference organization, which proved to be a valuable learning experience for a young scientist.

“I got to see the meticulous planning that goes into organizing a major scientific event,” he explained. “From coordinating with speakers and managing logistics to ensuring a seamless experience for all attendees, it really highlighted the importance of teamwork and attention to detail.”

Spanier said he received very positive feedback about the appeal of the university campus and its facilities. Several participants visited laboratories in the Science and Engineering Building as well as the Department of Nuclear Engineering, in addition to touring ORNL.

The next step for the organizers is putting together the workshop proceedings, which he said “will further promote UT as a vibrant place for research.”

BBC Science in Action artistic image of the universe

Tova Holmes Featured on BBC Science in Action

Artistic image from the BBC

In light of the June 11 report from the National Academies of Sciences, Engineering, and Medicine on a long-term vision for particle physics, Assistant Professor Tova Holmes spoke with the BBC’s Science in Action program to share her insights on a muon collider and what it means for the level of “Higgsiness” in the universe and “the beautiful benefit to society” from fundamental research.

A Photo of Tova Holmes

Tova Holmes Wins Simons Foundation Support for Muon Collider Groundwork

A Photo of Tova Holmes
Tova Holmes

Assistant Professor Tova Holmes is part of a scientific trio that won $1 million from the Simons Foundation to break new ground in particle physics and train young scientists to explore it.

The proposal is one of only two the foundation funded this year through its Targeted Grants in Mathematics and Physical Sciences program. The two-year grant allows Holmes and her co-investigators to do crucial groundwork for building a muon collider. This next-generation facility is part of the nation’s particle physics roadmap, designed to deliver the energy upgrades needed to untangle mysteries about dark matter and what holds the universe together.

To reach this goal, the grant supports young researchers working at the intersection of experimental particle physics and accelerator physics. Scientists have spent decades developing instruments to study matter’s building blocks. Now those tools are commonly used in fields like medical imaging and making semiconductors. Holmes and her colleagues (Isobel Ojalvo of Princeton University and Karri DiPetrillo of the University of Chicago) want universities to play a bigger role in educating scientists who understand this technology to ensure its progress for science and society.

Catching Muons While You Can

Holmes met Ojalvo and DiPetrillo working at the Large Hadron Collider (LHC), the world’s most powerful particle accelerator. Revving up to just about the speed of light, the LHC collides two beams of particles at different spots along a circular scientific racetrack. Experiments at the collision points detect and analyze the results, looking for escapees, debris, new particles, and extra dimensions. The LHC was home to breakthrough science confirming the Higgs boson, the particle whose associated field gives other fundamental particles their mass.

For many scientists (including Holmes and her colleagues) the muon collider is the next frontier for particle physics. Typical colliders rely on proton or electron beams. Protons are composite particles and when they collide, only fractions of their energy (carried by quarks and gluons inside them) can be used to make new particles. Like muons, electrons don’t have any smaller constituents, but they are much lighter, making it impossible to accelerate them to high energies. Muon beams offer higher collision energy, producing more data and taking up less space. There’s a catch, however.

Holmes explained that stable particles like electrons and protons are plentiful and easy to manipulate into beams.

“Muons are not like that,” she said. “They’re constantly being produced in our atmosphere but they are not just sitting around. They only live two-millionths of a second … so you need to create them and then harness them before they disappear.”

Creating them isn’t the tough part. Corralling them is.

“If you take a bunch of protons and slam them into a target you can make muons,” Holmes explained. “But trying to gather them up, get them all aligned into a really tight beam and then manipulate, accelerate, focus, (and) collide them: that part hasn’t been done before. That is a really unique challenge.”

Dark Matter and the Fate of the Universe

Muons might be problematic, but Holmes has two targets in mind that make them worth the trouble: understanding dark matter and the life of the universe.

“As soon as people realized that there was dark matter out there they started trying to hypothesize what kind of particles this could be,” she said. “We haven’t been able to build something sensitive enough, and high-energy enough, to access it. I think we have a pretty good shot at that with a muon collider.”

A muon collider could also help explain what the Higgs boson is up to and what that means for the life (and maybe collapse) of the universe. It could mass produce collisions so energetic that they spawn multiple Higgs bosons, with interactions between those identical particles giving scientists a deeper understanding of how it works.

“The Higgs boson seems to be extremely essential to understanding the birth of our universe and possibly its death,” Holmes said.

The Higgs is like a play with three starring roles: The boson, the field, and the potential. Scientists know that the scenery includes a well, with a curve at the bottom.

“When the Higgs field fell into that well, something fundamental changed in the universe,” Holmes said. “Before that, everything was massless. Everything could interact on even footing. All of a sudden, particles acquired different masses. You have preferential interactions. That’s what creates our protons and our neutrons. That’s what creates all of matter.”

The Higgs potential might undo all that.

“Think about potentials as rolling hills,” Holmes explained. “You put something at the top; it rolls down and finds a minimum potential and it settles there.”

In a real landscape there might be another valley below, but if there were a hill between the two, nothing would happen. Unfortunately, Holmes added, “in quantum mechanics there’s a mechanism for tunneling through that hill. If that happens and the Higgs field finds a new potential minimum, it completely disrupts everything about the matter that we have around us. The universe would suddenly and dramatically completely reorder itself.”

Holmes said the beginning and end of the universe are tied to the shape of the Higgs potential and a “multi-Higgs factory is the only way that you can address those questions.”

Next-Gen Accelerator Scientists

The Simons Foundation grant will help Holmes and her co-investigators mentor young scientists who will help draw this factory’s blueprint. All three will take on postdocs and students, and they’ll jointly supervise their work. Specifically, they’ll work at the junction of experimental particle physics and accelerator physics.

“Accelerator physics is based in fundamental physics and is really driving a huge fraction of science today,” she said. “Accelerators have become massively useful to everyone,” across not only different fields of physics but also in the private sector.

While accelerators have their foundation in particle physics, Holmes said most students working in the field don’t get experience working with them because the research is centered primarily at national labs rather than universities.

“What we have is a field that everybody’s relying on that doesn’t have a pipeline of people to become the next generation who are able to create these incredible machines,” she explained. “We have a great program in the U.S. but it doesn’t have the number of people it should.”

The grant will fund students working on challenges in both the particle physics and accelerator aspects of building a muon collider, part of what Holmes calls the “pre-work” in mapping out its future. While the collider itself would takes years and substantial public investment, she said they want to demonstrate that the most technically challenging physical pieces of it are actually possible, with plenty to discover along the way.

“Even before you make the final collider there’s a lot of interest in thinking about what kind of experiments you could set up with that intermediate beam,” she said. “If you look somewhere you’ve never looked before, you don’t know what you’re going to see.”

Faculty members Steven Johnston and Tova Holmes at the College of Arts and Sciences Faculty Convocation Award Ceremony on March 31, 2025.

Holmes and Johnston Win CAS Honors

Faculty members Steven Johnston and Tova Holmes at the College of Arts and Sciences Faculty Convocation Award Ceremony on March 31, 2025.
Steve Johnston and Tova Holmes

Each year the College of Arts and Sciences honors faculty members who’ve excelled in teaching, advising, outreach, research and creative activity, and other aspects of the college’s mission. The Department of Physics and Astronomy was well-represented at the annual awards ceremony on March 31, when Assistant Professor Tova Holmes and Bains Professor Steve Johnston were recognized as outstanding researchers.

Understanding Matter’s Foundations

Holmes works in elementary particle physics and is deeply involved with research at the Large Hadron Collider at CERN. She started at the ATLAS Experiment and is now part of the CMS Experiment, which sorts through the results of the LHC’s powerful particle collisions to search for new particles (and new physics) using the Compact Muon Solenoid Detector. She’s also turned her attention to the promise of a muon collider to further test the limits of what we understand about the particles and forces that make up all matter. Since joining the physics faculty in 2020, Holmes has won significant support and recognition for her work. In 2022 she was awarded a U.S. Department of Energy Early Career Research Award. In 2024 she won the university’s first-ever Cottrell Award and earlier this year she was named a Sloan Research Fellow. The college presented her with an Excellence in Research and Creative Achievement Award (Early Career.)

Decoding Quantum Materials

While Holmes focuses on particles, Bains Professor Steve Johnston wants to understand how and why quantum materials behave the way they do. As a condensed matter theorist, he applies mathematical models to demystify the complex interactions in quantum systems—those that defy the rules of classical physics models and have the potential to revolutionize science and technology (e.g., superconductivity). Johnston joined the faculty in 2014. Since then he has won a National Science Foundation CAREER Award (2019), a UT Chancellor’s Citation Award for Extraordinary Professional Promise (2020), seen his research featured on the cover of Nature Physics, and played a key role in the university’s successful bid to win NSF funding for the Center for Advanced Materials and Manufacturing (CAMM). Last year the department named him the Elizabeth M. Bains and James A. Bains Professor of Physics and Astronomy, support that enables him to develop and share a collection of codes (called SmoQy) to describe new quantum materials without having to start from scratch. He was honored with the college’s Excellence in Research and Creative Achievement Award (Mid-Career.)

While Holmes and Johnston have both won campus and national honors, the department’s students are equally impressed with their work, having selected Holmes as the Society of Physics Students Research Advisor of the Year and Johnston as the Graduate Physics Society Graduate Teacher of the Year (both in 2023).

In the past 10 years, physics faculty members have won 11 college research and creative achievement awards. Learn more about all the 2025 convocation awardees from the College of Arts and Sciences newsroom.

A photo of Larry Lee

Larry Lee Named a Cottrell Scholar

Assistant Professor Larry Lee has been named a Cottrell Scholar, the second Cottrell Scholar Award for UT Physics in two years. The prestigious honor goes to early career teacher-scholars in chemistry, physics, and astronomy to support innovative research and academic leadership. Lee is one of 16 scientists selected for the 2025 class. The award will bolster his dedication to helping transfer students succeed at UT and further his research in accelerator physics.

Full story from UT News.

A photo of a student presenting research at the CPAD 2024 Workshop.

The (Particle) Detectorists

Photo of 2024 CPAD Workshop Attendees in front of Ayres Hall
2024 CPAD Conference Photo

If scientists want to know what makes up matter they have to sort and study the particles that compose it. That effort requires precision detectors. UT Physics and Oak Ridge National Laboratory (ORNL) hosted the 2024 Coordinating Panel for Advanced Detectors Workshop (CPAD) so physicists could exchange ideas about designing, building, and using these systems to explain how the universe works.

Some 260 participants attended the meeting, which ran November 19-22. With sessions covering topics from fast timing detectors to detector mechanics, they learned what works and what the next steps might look like in particle detection. They also had an opportunity to tour ORNL. Tova Holmes, an assistant professor of physics and a member of the workshop’s local organizing committee, explained why this research matters to everyone—not just scientists.

“Advancing detector technology drives our understanding of the universe,” she said, “but these detectors are also one of our most valuable contributions to society as particle physicists: modern medical scanning technology, nuclear non-proliferation technology; all of these emerge directly from particle physics. The CPAD workshop helps the community consolidate around the most promising ideas and drive them forward.”

In addition to the parallel and plenary sessions, students had the chance to share their research in a poster session, where UT’s Adam Vendrasco won a best poster design honorable mention for his project “Containerization of the Burn in Box Software for the CMS Outer Tracker Upgrade.” As a member of UT’s Compact Muon Solenoid (CMS) group, he’s part of a particle physics kinship that marked both loss and celebration during the week-long gathering.

A special memorial session honored Ian Shipsey, a foundational member of the community who passed away suddenly a month before the meeting. Among many contributions across the United States and Europe, Shipsey served as chair of the CMS experiment collaboration board, defined Fermilab’s Large Hadron Collider Physics Center, and was a founding chair of the CPAD organization—helping shape the scientific landscape students like Vendrasco are still exploring. 

The workshop also hailed the 50th anniversary of the Time Projection Chamber (TPC): physicist David Nygren’s innovative design to study tens of thousands of particles from a single collision event. A special plenary session included contributions from Nygren and leaders in the field who continue to use the TPC for discoveries today. A reception at the Sunsphere (with our own Bains Professor Steven Johnston signing on as DJ) was part of the celebration. Not to be outdone, Assistant Professor Larry Lee, Professor Norman Mannella, and local musician Dave Slack helped provide the musical backdrop for a closing banquet at the Knoxville Museum of Art.

Lee, who, like Holmes, invested hours of work in the event as part of the local organizing committee, had no doubts the effort was worth it.

“We were honored to host this important conference here on campus, bringing many of the world’s leaders in particle detection to Knoxville,” he said. “We had the opportunity to show the community the amazing research happening on campus and at ORNL, drive these historic special events, and plan for the future of particle physics. Not only did UT have a seat at the table; the table was in our living room.”

A photo of Tova Holmes

Cottrell Scholar Award for Tova Holmes

A photo of Tova Holmes
Tova Holmes

Tova Holmes is a big fan of tiny particles. She’d like it if you were too. An assistant professor of physics, she’s won a prestigious Cottrell Scholar Award to help her move physics forward while inspiring a larger cheering section for all science.

The Cottrell Scholar Awards recognize outstanding early-career teacher-scholars in chemistry, physics, and astronomy. Holmes is the first UT faculty member to win a Cottrell Award and one of 19 awardees in the 2024 cohort, each of whom receives $120,000 over three years. The goal is to support young scientists with innovative ideas who also have a gift for academic leadership. Each scholar writes a proposal for research and one for education. Holmes, who joined the faculty in 2020, is passionate about both. In 2023 UT’s physics majors selected her as their Research Advisor of the Year. As a Cottrell Scholar, she’ll teach students how to explain their work to a wide audience, as well as explore new ground for her own.

In the Room Where it Happened

In the early hours of July 4, 2012, Holmes, then a sleep-deprived graduate student, managed to get one of three remaining seats in the CERN auditorium to hear the official announcement that the Higgs boson had been discovered. The confirmation of this elusive particle, predicted 50 years earlier, completed the Standard Model of Physics. So on “Higgsdependence Day,” as she called it, Holmes was there, “at the center of discovery.” She was hooked.

Elementary particles are a bit like prime numbers. If you’re dividing a huge number, there comes a point where you can’t break it down any farther because the numbers left are indivisible. Atoms are sort of the same. Dividing an atom into its most minute components and figuring out how they work (or if there are more of them) takes scientists down to the bedrock of matter and tells them something about the universe, most of which is still a mystery. While the Standard Model organizes all the particles and forces governing matter, Holmes has set her sights on one: the muon.

Making Custom Particles

Digging down to matter’s foundations involves building high-energy colliders that accelerate beams of particles and then smash them together. Physicists wade through the aftermath, measuring the location and energies of known particles and looking for new ones. The Large Hadron Collider (LHC) at CERN has been remarkably successful at this, as evidenced by the Higgs discovery. But what comes next?

The LHC is a 27-kilometer underground ring crossing the French-Swiss border, hemmed in by mountains and Lake Geneva. To take the science farther and work at higher energies, the ring would have to be bigger. Holmes, however, is among the physicists who see energy, rather than real estate, as the solution. The muon is the key.

Muons are 200 times heavier than electrons and offer more energy for collisions. They also come with challenges. Particles in collision beams have to be aligned and headed in the same direction. For that to work, every collider up until now has used stable particles, like the protons at the LHC. Muons are more complicated. First, they have to be created by sending protons through a scientific obstacle course that begins with a linear accelerator and ultimately creates particles called pions, which decay into muons.

“They’re bespoke particles,” Holmes said. “You have to make them because they’re not sitting around. Then you have to deal with them in whatever state they’re in. (And) they only live about two microseconds.”

Before the muons decay, scientists have to compress them to fit into a beam, point them in the same direction, accelerate them, and finally collide them.

“That’s going to make things tricky,” Holmes said.

She’s is part of a growing group with a plan to navigate this tricky territory. Using magnets to collect the muons, they can slow them down by shooting them into a material, then accelerate them in one direction to align them. This is only one part of a muon collider, but by showing proof of principle, they move closer to making the technology a reality.

Their timing couldn’t be better.

The US particle physics community sees the muon collider as a centerpiece of the field’s future, as outlined in the scientific roadmap they announced last year. The Cottrell Award helps support Holmes’s postdocs and students so they can contribute to this work.

“What they’re currently doing is muddling their way through some pretty rough code that’s sort of been borrowed and adapted, and trying to squeeze information out of it about what kind of physics we can do,” she said. “We need to (make) that a more streamlined process. The proposal is really about engaging in that.”

Department Head Adrian Del Maestro said Holmes “is unique in her ability to inspire and challenge students to seek answers to some of the most fundamental problems in physics. She is an international leader in envisioning the future of the facilities needed to discover new particles, making the University of Tennessee a ‘theory of everything’ school.”

Getting the Message Across

Holmes’s students have joined a field that’s highly collaborative. She said creative thinking and effective communications are crucial in research areas like hers that involve thousands of scientists from across the world. Yet she’s seen that students typically don’t get the chance to develop those skills in the mainstream physics curriculum. Not only does this discourage students drawn to those ideas from majoring in physics, it also leaves physics graduates at a disadvantage.

“You’re not going to be good in my field if you can’t communicate to nearby experts,” she explained, adding that half of success in particle physics is explaining how what you learn is useful to others.

“(Communication) is not an afterthought: it’s a fundamental requirement,” she said. “My field’s not the only one that’s like that.”

Holmes was impressed by Professor David Matthew’s architecture and interior design students as she watched them brainstorm, refine, and work together to solve problems. She took notice of Senior Lecturer Sean Lindsay’s innovative course using science fiction to teach physics. Both also use a grading system outside the traditional instructor-assigned scores, encouraging students to self-assess and review one another’s work. She’s brought Matthews and Lindsay on board as collaborators as she uses her Cottrell Award to develop a special topics course.

Students will learn the basics of strong visual, written, and spoken communications. They’ll study design elements to make compelling graphics for their data and practice translating technical concepts into simpler language. Their final project will be convincing a non-scientist to see the value in science.

Holmes knows first-hand that discovery must be shared if it’s going to be appreciated. She’s been quoted in The New York Times, Nature, and Science about the possibility of a muon collider and what it means inside and outside the research community.

“If I want to get a multi-billion-dollar machine built in the US, I need to be able to communicate why that’s something that’s valuable to everybody in the US,” she said.

A Career Well Spent

Holmes is excited to broaden her own collaborations now that she’s part of the Cottrell Scholars community. Current and former scholars meet each year and build connections outside their typical research areas. While she has a scientist’s natural curiosity and open mind, her hope is that particle physics—driven by a new muon collider—will keep her occupied for the foreseeable future.

“That is my dream,” she said. “I think that would be a career well spent.”

George Siopsis and Joon Sue Lee

Alumni Association Honors Lee and Siopsis for Teaching and Distinguished Service

Joon Sue Lee with Mike McKay and Brian Winbigler at UTAA Faculty Awards Ceremony
Joon Sue Lee (center) with Mike McKay (UTAA) and Brian Winbigler (UTAA Board of Governors)
George Siopsis with Mike McKay and Brian Winbigler at UTAA Faculty Awards Ceremony
George Siopsis (center) with Mike McKay (UTAA) and Brian Winbigler (UTAA Board of Governors)

Joon Sue Lee and George Siopsis joined UT nearly three decades apart, but their shared commitment to the university’s mission transcends generations. The University of Tennessee Alumni Association (UTAA) has honored that dedication by recognizing Lee with an Outstanding Teacher Award and Siopsis with a Distinguished Service Professorship.

“The department was delighted to learn about the well-deserved alumni recognitions for Assistant Professor Joon Sue Lee and Professor George Siopsis, who both exemplify our training and knowledge-creation mission,” said Adrian Del Maestro, professor and department head. “Their passion for teaching and research in quantum technologies has played a large role in UT’s growing national and international prominence in this exciting area crucial for U.S. competitiveness.” 

Developing Self-Reliant Thinkers

This is the second teaching honor this year for Lee, an assistant professor. UT’s College of Arts and Sciences presented him with an Excellence in Teaching Award at the annual faculty convocation. Since joining the physics faculty in 2020, Lee has taught undergraduates enrolled in Thermal Physics, Electricity and Magnetism, Electronics Lab, and Modern Physics Lab. His approach—especially to teaching labs—equips students with an understanding of physics fundamentals as well as the hands-on experience they need for careers in academe, technology, and industry.

“What has surprised me most about teaching is the impact that a collaborative and supportive learning environment can have on students’ engagement and development,” he said. “I have seen how nurturing critical thinking and fostering a dynamic partnership can transform the learning experience, and witnessing this has been greatly rewarding.”

Lee’s teaching isn’t limited to the classroom. His research centers on developing quantum materials and devices. Students in his group learn from and contribute to the work.

“What I like best about teaching is the opportunity to guide students as they navigate complex concepts and develop into self-reliant thinkers,” he said. “Mentoring students in my research lab and seeing them grow into independent researchers through the continuous exchange of ideas and collaborative processes is deeply fulfilling.” 

Because the UTAA awardees are selected by a committee comprising alumni, Student Alumni Associates, and prior honorees, Lee and Siopsis were chosen in part by their peers, which Lee said is profoundly meaningful.

“The acknowledgement from my fellow faculty members, who understand the complexities and challenges of teaching, affirms the dedication and effort I put into creating an effective learning environment,” he said. “Additionally, being chosen by UT graduates highlights the impact of my teaching, extending beyond the classroom and into the students’ lives as alumni.”

Nurturing the Next Generation

For Siopsis, the UTAA Distinguished Service Professorship has encouraged him to reflect on his many accomplishments while thinking about what comes next.

“Receiving this distinguished faculty award makes me feel deeply honored and appreciated,” he said. “It’s a mix of gratitude, validation, pride, humility, motivation, and a sense of responsibility. This recognition not only celebrates past achievements but also inspires me to continue making meaningful contributions to my field, the broader academic community, and the UT family.”

Siopsis came to UT Physics in 1991 and has balanced teaching, research, and service ever since. He’s taught courses from the fundamental (Elements of Physics) to the complex (Quantum Field Theory). He’s served as director of the Governor’s School for the Sciences and Engineering. A theoretical particle physicist, he specializes in quantum computing and networking, which heavily influences his current priorities. He’s built strong collaborations with partners from other universities, industry, and national laboratories with two aims in mind: developing quantum network applications and drawing on this emerging field to foster economic and technological growth in Appalachia.

Of all his endeavors, Siopsis said he is most proud of his leadership role in the Appalachian Quantum Initiative (AQI) and his work to bring UT to the forefront of emerging quantum technology. The AQI connects university researchers in the Southeast with industry partners to develop quantum software for scientific and engineering applications. This includes a quantum curriculum and workforce development component in partnership with other universities, industry, and national labs. In that vein, he and colleagues from the University of Georgia won $3M from the National Science Foundation to launch an interdisciplinary training program for graduate students. Siopsis develops and teaches classes and seminars in quantum technologies and is currently supervising or co-supervising the work of 11 graduate students.

This, he said, is part of his dedication to “nurturing the next generation of scientists in the emerging quantum field.”

Siopsis also draws on his expertise to lead a university-national laboratory project to develop a quantum regional network and pointed out that the Knoxville Chamber included the installation of a quantum network from Oak Ridge National Laboratory to UT as a goal in their 2030 Protocol plan.

Siopsis and Lee were recognized with their fellow awardees at a Faculty Awards Dinner on May 31. The UTAA presented 11 Outstanding Teacher Awards, two Public Service Awards, and six Distinguished Service Professorships this year, honoring outstanding faculty from across the University of Tennessee family. The association serves more than 445,000 graduates of the UT system through networking opportunities, legislative advocacy, career services, and alumni benefits, among other initiatives.

Cover Image of Science Magazine 29 March 2024, Used with Permission

The Art of Muon Collisions

Image of Science Magazine Cover 29 March 2024, Used with Permission
Credit: Reprinted with permission from AAAS; See Terms & Conditions below
Image of Tova Holmes
An image of Lawrence Lee
Charles Bell

Tova Holmes, Larry Lee, and Charles Bell

Assistant Professors Tova Holmes and Larry Lee are particle physicists and in their line of work, to think big, you have to think small. That’s where muons come in, and it’s how they became part of a Science Magazine story—including creating the cover art.

In “The Dream Machine,” journalist Adrian Cho reviews the newly-drawn roadmap for particle physics research in the United States. For the past century, physicists have designed, built, and deployed powerful accelerators that rev up and collide particles, precisely measuring the fragments and tracking the escapees to learn more about the building blocks of matter that make up the universe. With current instruments here and abroad reaching their energy limits, American physicists are looking at three possible types of colliders to replace them. Among them is a muon collider.

Will the Muon Have Its Moment?

Muons are fundamental particles. They’re quite a bit like electrons, but roughly 200 times heavier. Until now protons and electrons have been the particles of choice for collider physics, but with their extra mass muons are good candidates for collisions at energy scales up to 10 times higher than that of the Large Hadron Collider, the current world leader. As an early-career scientist, Holmes explained to Cho that waiting something like another five decades for a next-generation collider means the particle physics research she’s so passionate about would pass her by.

“I will be definitely not still working, possibly not alive,” she said.

That’s why she and Lee have spent nearly four years creating designs for a possible muon collider. Holmes coordinates the US-based research and development program for tracking detectors. (Her work has won her a Department of Energy Early Career Research Award, as well as place among the 2024 Class of Cottrell Scholars.) In her conversation with Cho she referred him to Lee as a source for images that could further describe the muon collider vision and enhance the article. Like Holmes, Lee has a strong belief in the power of imagery to convey scientific concepts, so he gladly accepted the assignment.

Renaissance and Romance

Planning for a muon collider is one thing. Promoting the idea to stakeholders is another. Holmes and Lee saw right away that the imagery accompanying those pitches didn’t always match the excitement for the collider’s promise.

In particle physics, “we have a long history of making what are called event displays,” Lee explained, which are simply visualizations of individual collision events. He said scientists have field-specific tools to create those displays, but the results look technical and aren’t particularly engaging.

“One thing I’ve wanted to do for a long time was bring in modern 3D environment modeling to essentially do the same thing, but in a slicker way,” he said.

With UT’s particle physicists’ involvement in the muon collider—specifically a conceptual design for a detector—he saw a fantastic opportunity.

“Right now, if we’re talking about the detector, we’re just in the design phase,” Holmes explained. “We write down some parameters, we try and visualize it, we simulate it, we shoot fake particles into it in our simulation, (and) we see what we can do to reconstruct it.”;

Lee enlisted Undergraduate Physics Major Charles Bell to help create a visualization of the detector and what the particles inside it might look like. They started with proprietary formats familiar to particle physics and brought in industry standard tools, ultimately incorporating Unreal Engine, a creative suite used for an array of simulation purposes. The resulting images were stunning enough to land on the cover of Science and alongside Cho’s article.

While standard event displays are great for showing off technical details, the new artistic images add another layer of strategic communication.

“Larry was trying to make a version of them that took advantage of all the tools that are out there to make them both useful and beautiful,” Holmes said. “Improving this kind of visual translation is really important for the future of our field because we have to be able to explain the kind of exploration we’re doing through visual media.”

Holmes said the muon collider’s success is dependent on audiences both inside and outside physics. At present only a few hundred scientists the world over are involved in the project.

“There have been past versions of this muon collider effort where the technology was not really close enough to ready for people to take it seriously as the next thing,” she said. “It needs to grow to happen. That means getting more people interested. It also needs the engagement of the field to get support from funding agencies. Being able to communicate clearly the excitement, and make sure that communication gets in people’s laps, matters.”

She’s hopeful Lee’s images will inspire a “renaissance” where researchers look at the technological progress surrounding the muon collider and see its potential in a new light. They both also want the public to become more excited about the science behind, literally, everything.

“In astrophysics it’s very easy to visualize because we take literal photographs of the universe,” Holmes said. “For us (in particle physics), we can’t take literal photographs. We do something similar with our detector reconstruction, but it doesn’t look like a photo.”

Lee said he wants images like those he created for the muon collider project to tie in to the “romantic big picture” of fundamental science and capture human imagination.

“We both feel very strongly that it’s important to make things visually compelling, because once you do, people remember them,” he said, even if they don’t fully understand the science behind the pictures.

“This was something we’ve been talking about in the muon collider effort because you’re asking the public to embrace a big project and if you can’t explain what it’s for, you have a real problem,” Holmes said.

This isn’t her first foray into art where the collider’s concerned: she created a poster that’s hanging in a good many physics departments as well as swag to promote the project.

Holmes and Lee believe that prioritizing compelling science communication isn’t just a feel-good pursuit: it’s a key to helping serious science thrive.

“This work is important,” Lee said. “It’s not purely outreach; it’s not purely just for fun. It really pushes us to the literal front of the journal.”

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