Professor William Dorland was honored with the American Physical Society’s (APS) 2024 James Clerk Maxwell Prize for Plasma Physics for “pioneering work in kinetic plasma turbulence that revolutionizes turbulent transport calculations for magnetic confinement devices and inspires research in astrophysical plasma turbulence". This honor was shared with Greg Hammett, Dorland’s doctoral advisor from Princeton University. Professor Dorland died on September 22, 2024, just days after the announcement. 

The James Clerk Maxwell Prize annually recognizes outstanding contributions to the field of plasma physics.  The prize is named after a nineteenth century Scottish physicist known for his work with electricity, magnetism and light.Bill Dorland (photo by Mark Sherwood)

Dorland graduated with a B.S. in physics (with special and highest honors) from the University of Texas in 1988, and received his Ph.D. in Astrophysical Sciences from Princeton University in 1993. He also earned a Master’s degree in Public Affairs from the Princeton School of Public and International Affairs in 1993, after completing a course of study focused on international science policy.

He then accepted an appointment as a Department of Energy Fusion Postdoctoral Fellow at the Institute for Fusion Studies of the University of Texas and rose to the rank of Associate Research Scientist before joining the University of Maryland in 1998. He holds a joint appointment in Physics and the Institute for Research in Electronics and Applied Physics (IREAP). Dorland has been a Visiting Professor of Theoretical Physics at the University of Oxford since 2010 and held a previous appointment in the Department of Physics of Imperial College, London. From 2020-23, he served as Associate Laboratory Director for Computational Science at the Princeton Plasma Physics Lab.

In 2005, Dorland was elected a Fellow of the APS Division of Plasma Physics. He won the Department of Energy’s 2009 E. O. Lawrence Medal for “his scientific leadership in the development of comprehensive computer simulations of plasma turbulence, and his specific predictions, insights, and improved understanding of turbulent transport in magnetically-confined plasma experiments”.

Dorland is a UMD Distinguished Scholar-Teacher, a recipient of the Richard A. Ferrell Distinguished Faculty Fellowship and a Merrill Presidential Faculty Mentor. He served as Director of the UMD Honors College for seven years, and afterward was cited with an Honors College Outstanding Faculty Award. Three of Dorland’s undergraduate mentees have received the University Medal.  He has been active in professional societies, contributing to APS advocacy for the international freedom of scientists, human rights and national security. He has published more than 150 journal articles.

“With his brilliant insights, Bill Dorland has fundamentally transformed the exploration of turbulence in fusion and astrophysical plasmas, and the Maxwell Prize is an immense and appropriate honor,” said Physics chair Steve Rolston. “In addition, he has been an extraordinary teacher, fantastic colleague and superb mentor. I could not be happier about this recognition.”

The prize carries a $10,000 stipend. UMD physicists who have won the Maxwell Prize include Tom Antonsen,  Phillip A. Sprangle, Roald Sagdeev, James Drake, Hans R. Griem, and Ronald C. Davidson.

Bill Dorland died days after this story was published. Read more about him here: https://umdphysics.umd.edu/about-us/news/department-news/1982-dorland.html

For the last four years, Aneesh Anandanatarajan has kept a running list of “big questions” about the universe and how it works. He started the list in high school but shows no signs of slowing down in his senior year as an astronomy and physics dual-degree student at the University of Maryland.Aneesh Anandanatarajan

“I am the type of person to ask questions until someone tells me to stop,” Anandanatarajan said. “I have about 40 questions on my list, and I like to return to them to see how I’ve progressed in terms of what I've learned and what I’m interested in.”

One of his early questions—how are electricity and magnetism related?—was written at a time when Anandanatarajan knew little about plasma astrophysics. Now, he’s conducting research in Physics Assistant Professor Sasha Philippov’s lab, where he uses physics-based simulations to study the turbulent environment and complex electromagnetic interactions around supermassive black holes.

While Anandanatarajan loves asking questions, he’s happiest sharing what he learned with others. As the tutoring chair for UMD’s Society of Physics Students, Anandanatarajan has become a physics ambassador while strengthening his knowledge of the subject.Aneesh Anandanatarajan and Othello Gomes

“As a tutor and as the tutoring chair, it has been important to me to know physics well. I want to fully understand where these different concepts and equations come from,” Anandanatarajan said. “One of the things I'm most excited about is sharing physics with other people.”

Virtually hooked

Anandanatarajan has been interested in exotic objects like black holes and neutron stars since middle school, but he didn’t discover this passion in a lab or a planetarium. While watching YouTube one day, he found a channel with buzzy animated videos about popular science topics, including astronomy and physics. A few videos later, he was hooked.

“It captured my interest in more ways than I expected because I didn’t really know much about those subjects before middle school,” he said. “Over time, I watched more videos and realized that astronomy might be something I’d like to learn more about at an academic and professional level.”

Anandanatarajan said he was initially attracted to UMD’s “great astronomy program,” but he was thrilled to learn that he could add a second degree in physics by taking a few more classes. He’s enjoyed learning from professors who are exploring diverse fields of research.

“There are a lot of really great research topics here at Maryland and professors that are doing active research in those fields,” he said. “I’ve had a lot of great experiences with professors that want me to succeed and have pushed me to succeed.”

One of those professors is Philippov, whom Anandanatarajan started working with in spring 2024. Philippov studies high-energy astrophysics through a blend of theory and computer modeling with a focus on the physics of plasmas—hot, ionized gas surrounding black holes, neutron stars and other celestial objects. 

Anandanatarajan is using computer simulations to study how plasmas composed of electrons and positrons interact with other particles in the corona, an extremely hot and highly magnetized region that surrounds black holes, our sun and other space objects. Through a process called annihilation, these interactions can produce gamma rays, a type of radiation that astronomers can study to learn more about the universe.

“The corona is a very mysterious region that a lot of astronomers are very interested in probing,” Anandanatarajan said. “It’s essentially a breeding ground for electromagnetic activity, so we'd like to understand the phenomena that occur in that region because there are a lot of unknowns when it comes to our observations.”

Through this research, Anandanatarajan learned how to run Monte Carlo simulations that predict the probability of different outcomes—a skill that proved useful on other projects, like the up-and-coming study of high-energy particle collisions.

When interests collide

During the spring 2024 semester, a project in Physics Assistant Professor Christopher Palmer’s PHYS 441: “Introduction to Particle Physics” course let Anandanatarajan play an unexpected role in the next Large Hadron Collider (LHC).

During the course, Palmer teamed up with faculty at MIT to give students a front-row seat to discussions involving the Future Circular Collider (FCC), a proposed collider that would push the boundaries of particle physics beyond the capabilities of the LHC. The hope is that an upgraded collider could discover new particles or find evidence that deviates from the Standard Model of physics, which describes the fundamental forces that shape the universe.

Anandanatarajan and other students at UMD and MIT analyzed Monte Carlo simulations to determine how to precisely measure novel processes produced in electron-positron collisions from the FCCee accelerator, the first stage of the FCC.

“Essentially what we wanted to do was characterize different kinematic properties, such as the energy, momentum and angles at which these produced particles came out,” Anandanatarajan explained.

In March, this culminated in a visit to the second annual FCC workshop, where students presented their projects and spoke with leaders in the field.

“We learned a lot about how high-energy physics is conducted and the planning that is needed for a mega collider that may or may not be built 30 years from now,” Anandanatarajan said. “We talked to many different experts in the field who were thankfully friendly and willing to talk to undergrads about these types of topics.”

This experience initially felt disparate from his other projects, but Anandanatarajan realized that electron-positron collisions and large Monte Carlo simulations play an important role in astrophysics, too. After he earns his undergraduate degree, Anandanatarajan plans to continue studying astrophysics in a Ph.D. program that will allow him to keep asking—and answering—those big questions he’s carried with him for years.

Until then, he looks forward to spending his senior year sharing his passion with anyone willing to listen. He has several ideas for the Society of Physics Students—including a possible YouTube channel, harking back to his initial inspiration—to get students more engaged in physics.

“Making people excited about physics has always been a passion of mine,” he said. “I feel like I enjoy physics more than the average person, so I want to share those feelings with others and show them all of the cool things that physics has to offer.”

It is with much sadness that the Department of Physics announces the passing of several members of our community.

• Melanie Knouse Cline, a coordinator in the Maryland Center for Fundamental Physics (MCFP), died on June 3, 2024.
• Robert Dewar, a former postdoctoral associate, died on April 5, 2024.
• Robert Goldstein, an alumnus, died on Sept. 4, 2024.
• Charles Hussar, an alumnus and donor, died on March 30, 2024.
• Verne Kauppe (B.S., '71), who worked in multisensor and microwave remote sensing, died on September 8, 2024.
• William Kuperman (Ph.D., '72), former Director of the Marine Physical Laboratory of the Scripps Institution of Oceanography,  died on June 30, 2024. 
• Ernest Madsen (B.S. and M.S.), a medical physicist at the University of Wisconsin, died on August 24, 2024.
• Martin Vol Moody, an experimentalist working on gravitation, died on August 18, 2024.  
• Robert L. Parker, (Ph.D.,'60) who worked in metallurgy for the U.S. government, died on April 21, 2024.
• Joseph Perez (Ph,D., '68), former head of the Auburn University Physics Department, died on July 25, 2024.
• Edward "Joe" Redish, an acclaimed researcher and Professor Emeritus, died on August 24, 2024.
• Paul Richardson, a physicist with the U.S. Bureau of Mines, died on May 29, 2024.

Those who say there’s “nothing new under the sun” must not know about NASA’s Parker Solar Probe mission. Since its launch in 2018, this spacecraft has been shedding new light on Earth’s sun—and University of Maryland physicists are behind many of its discoveries.

At its core, the Parker Solar Probe is “on a mission to touch the sun,” in NASA’s words. It endures extreme conditions while dipping in and out of the corona—the outermost layer of the sun’s atmosphere—to collect data on magnetic fields, plasma and energetic particles. The corona is at least 100 times hotter than the sun’s surface, but it’s no match for the spacecraft’s incredible speed and carbon composite shield, which can survive 2,500 degrees Fahrenheit. Last year, the spacecraft broke its own record for the fastest object ever made by humans. Parker Solar Probe (courtesy of NASA)

This engineering feat was built to solve solar mysteries that have long confounded scientists: What makes the sun’s corona so much hotter than its surface, and what powers the sun’s supersonic wind? These questions aren’t just of interest to scientists, either. The solar wind, which carries plasma and part of the sun’s magnetic field, can cause geomagnetic storms capable of knocking out power grids on Earth or endangering astronauts in space.

To better understand these mechanisms, the Parker Solar Probe will attempt its deepest dive into the corona on December 24, 2024, with plans to come within 3.9 million miles of the sun’s surface. Researchers hope its findings will help them predict space weather with greater accuracy and frequency in the future.

James Drake, a Distinguished University Professor in UMD’s Department of Physics and Institute for Physical Science and Technology (IPST), is helping to move the needle closer to that goal as a member of the Parker Solar Probe research team.

“This mission is what's called a discovery mission, and with a discovery mission we can never be sure what we're going to find,” Drake said. “But of course, everybody is most excited about the data that will come from the Parker Solar Probe getting very close to the sun because that will reveal new information about the solar wind.” 

Reconnecting the dots

Drake and Marc Swisdak, a research scientist in UMD’s Institute for Research in Electronics & Applied Physics (IREAP), have been involved with this mission since its inception. The researchers were asked to join because of their expertise in magnetic reconnection, a process that occurs when magnetic fields pointing in opposite directions cross-connect, releasing large amounts of magnetic energy.

Before the Parker Solar Probe, it was known that magnetic reconnection could produce solar flares and coronal mass ejections that launch magnetic energy and plasma out into space. However, this mission revealed just how important magnetic reconnection is to so many other solar processes. 

Early Parker Solar Probe data showed that magnetic reconnection was happening frequently near the equatorial plane of the heliosphere, the giant magnetic bubble that surrounds the sun and all of the planets. More specifically, this activity was observed in the heliospheric current sheet, which divides sectors of the magnetic field that point toward and away from the sun. 

“That was a big surprise,” Drake said of their findings. “Every time the spacecraft crossed the heliospheric current sheet, we saw evidence for reconnection and the associated heating and energization of the ambient plasma.”

In 2021, the Parker Solar Probe made another unexpected discovery: the existence of switchbacks in the solar wind, which Drake described as “kinks in the magnetic field.” Characterized by sharp changes in the magnetic field’s direction, these switchbacks loosely trace the shape of the letter S.

“No one predicted the switchbacks—at least not the magnitude and number of them—when Parker launched,” Swisdak said. 

To explain this odd phenomenon, Drake, Swisdak and other collaborators theorized that switchbacks were produced by magnetic reconnection in the corona. While the exact origin of those switchbacks hasn’t been definitively solved, it prompted UMD’s team to take a closer look at magnetic reconnection, especially its role in driving the solar wind.

“The role of reconnection has gone from something that was not necessarily that significant at the beginning to a major component of the entire Parker Solar Probe mission,” Drake said. “Because of our group's expertise on the magnetic reconnection topic, we have played a central role in much of this work.”

Last year, Drake and Swisdak co-authored a study with other members of the Parker science team that explained how the sun’s fast wind—one of two types of solar wind—can surpass 1 million miles per hour. They once again saw that magnetic reconnection was responsible, specifically the kind that occurs between open and closed magnetic fields, known as interchange reconnection.

To test their theories about solar activity, the UMD team also uses computer simulations to try to reproduce Parker observations. 

“I think that one of the things that convinced people that magnetic reconnection was a major driver of the solar wind is that our computer simulations were able to produce the energetic particles that they saw in the Parker Solar Probe data,” Drake said. 

As part of his dissertation, physics Ph.D. student Zhiyu Yin built the simulation model that is used to see how particles might accelerate during magnetic reconnection.

“Magnetic reconnection is very important, and our simulation model can help us connect theory with observations,” Yin said. “I'm really honored to be part of the Parker Solar Probe mission and to contribute to its work, and I believe it could lead to even more discoveries about the physics of the sun, giving us the confidence to take on more projects in exploring the solar system and other astrophysical realms.”

Swisdak explained that simulations also help researchers push past the limitations of space probes.

“Observations are measuring something that is real, but they’re limited. Parker can only be in one place at one time, it has a limited lifetime and it’s also very hard to run reproducible experiments on it,” Swisdak said. “Computations have complementary advantages in that you can set up a simulation based on what Parker is observing, but then you can tweak the parameters to see the bigger picture of what we think is happening.”

‘Things no one has seen’

There are still unsolved mysteries, including the exact mechanisms that produce switchbacks and drive the solar wind, but researchers hope that the Parker Solar Probe will continue to answer these and other important questions. The sun is currently experiencing more intense solar flares and coronal mass ejections than usual, which could yield new and interesting data on the mechanisms that energize particles in these explosive events.

This research also has wider relevance. Studying the solar wind can help scientists understand other winds throughout the universe, including the powerful winds produced by black holes and rapidly rotating stars called pulsars. Winds can even offer clues about the habitability of planets because of their ability to deflect harmful cosmic rays, which are forms of radiation.

“One of the reasons why the solar wind is important is because it protects planetary bodies from these very energetic particles that are bouncing around the galaxy,” Drake said. “If we didn't have that solar wind protecting us, it's not totally clear whether the Earth would have been a habitable environment.”

As the spacecraft prepares for its December descent into the sun, the UMD team is eager to see what the new observations will reveal.

“One of the nice things about being involved with this mission is that it’s a chance to make observations of things that no one has seen before. It lets you go into a new regime of space and say, ‘Alright, we thought things would look this way, and inevitably they don't,’” Swisdak said. “The ability to get close enough to the sun to see where the solar wind starts and where coronal mass ejections begin—and being able to take direct measurements of those phenomena—is really exciting.”

For students interested in experimental research, there is no substitute for performing experiments in a lab. Working in a lab is invaluable for picking up important skills and learning if a research area is a good fit.

For senior physics and mathematics double major Patrick Chen, who plans to pursue experimental physics in the future, UMD has provided ample opportunities for hands-on experience. Throughout his time at UMD, Chen has taken the initiative to work outside his classes and get practical lab experience. This summer an endowed undergraduate award allowed Chen to further expand that experience by funding his travel to Oak Ridge National Laboratory (ORNL) in Tennessee. At the lab, he bombarded samples with neutrons from a nuclear reactor in experiments he had previously only been able to simulate. 

“I always enjoyed hands-on stuff,” Chen said. “I was really compelled to want to see what it's actually like doing the experiments and whether that's something I actually like, as well as to learn about the process and see what it's like to travel to these facilities to go do work.”

The trip provided Chen with practical experience using lab equipment that requires large, specialized facilities—like a nuclear reactor. It also gave him a broader perspective on the reality of being an experimental physicist. The insights and experiences come at a critical time as Chen begins his senior year and considers his options for graduate school and professionally pursuing physics. Patrick Chen

Chen’s opportunity to visit ORNL was built on a foundation of research experience that he has been establishing throughout his time at UMD. He got an early start exploring research. The summer before his freshman year, he came to campus early and participated in UMD’s Toolkit for Success program. The program, run by Donna Hammer, the physics director of education, and Angel Torres, the physics outreach coordinator, helps students build skills and explore career options through physics and math lessons, a research project and meetings with professionals from industry, government, and academia.

“I think that program is really great, but also after coming to UMD, Angel and Donna have been incredibly helpful if I have any questions or need anything,” Chen said. “They're always there for me and they've been very helpful during my time here at UMD in navigating the physics department and making me aware of opportunities.” 

During Chen’s freshman year, he kept an eye out for more opportunities to get research experience. He attended a department event where members of several labs presented their research to students. The work being performed in the lab of Nick Butch, an Adjunct Associate Professor of physics at UMD and a Physicist at the NIST Center for Neutron Research, caught Chen’s attention, and Butch welcomed Chen into the lab when he reached out. Initially, Chen mainly served as an extra pair of hands around the lab, assisting with activities like processing data that labmates had collected and programming the heating cycles on the furnaces used to fabricate materials.

Eventually, Butch created a project for several undergraduate students to work on as a group, aiming to provide them with experience in the research area of condensed matter physics, which he specializes in. The topic deals with how particles, particularly electrons, interact to produce the emergent properties of a material, and classes on condensed matter are generally taught at the graduate level, which can make it tricky for undergraduate students to explore an interest in the topic. 

“We make our own materials, so the benefit of having undergrads work on that kind of research is that it doesn't actually necessarily require a lot of physics classroom knowledge to get started,” Butch said. “The way that I have it set up, we don't necessarily have the students sitting and doing heavy analysis that is requiring a lot of mathematics or anything like that.”

In the project, the students make a variety of material samples themselves and then measure the properties of the materials. Since the students work as a group and individuals can come and go, it gives them a chance to explore condensed matter research, without the hassle of starting a project from scratch or experiments being left unfinished if they’re a bad fit for a particular student. Chen and a few of his classmates have kept the project going over the past couple of years, and by working together they can schedule around their classes and steadily maintain progress improving the processes, making new materials and refining their measurement skills.

“Patrick is a wonderful student,” Butch said. “I look forward to seeing impressive things from him in the future.”

When Chen started looking for summer research opportunities in 2023, Butch encouraged him to apply to the Summer Undergraduate Research Fellowship (SURF) at NIST, which is supported by the Center for High Resolution Neutron Scattering. Chen did, and the program accepted him. He was assigned to work with NIST Instrument Scientist Jonathan Gaudet who works at the NIST Center for Neutron Research. Gaudet gave Chen a project exploring the magnetic behaviors of materials called Weyl semimetals. 

When studying Weyl semimetals and other materials, researchers, like Gaudet, often rely on neutron scattering experiments to study the material. In the experiments, researchers shoot neutrons through a material, which provides them with an up-close image of the structure of materials—kind of like a microscope. 

But unlike a microscope that uses visible light, neutron scattering doesn’t just provide an image of the surface. Neutrons can pass through solid objects without much chance of interacting since they don’t have an electrical charge—meaning they don’t interact with the outer shell of electrons of an atom and must hit the much smaller target of the nucleus to interact. If researchers send enough neutrons into a material, a few will collide and be deflected from their original path. Researchers can analyze where the deflected neutrons are sent to determine the hidden structure they interacted with inside the material. 

Unfortunately, the NIST Center for Neutron Research is in the middle of an extensive repair and upgrade project, so the equipment for performing neutron scattering experiments has been unavailable for use. Since Chen couldn’t perform measurements at NIST to observe the structure of real Weyl semimetals, he had to pursue an alternative method of investigation—simulating the materials on a computer.

Chen’s efforts last summer produced a simulation that he used to predict how neutrons would scatter through Weyl semimetals. But Chen still wanted to perform real neutron scattering experiments himself. So, he was interested when Gaudet mentioned an upcoming trip to ORNL that Chen could join. However, to take the opportunity, Chen had to cover his travel expenses. He applied for a College of Computer, Mathematical, and Natural Sciences Alumni Network Endowed Undergraduate Award and obtained the necessary funding. He was one of only nine students from across the entire College of Computer, Mathematical, and Natural Sciences to receive funding through the program this year.

With the money, Chen was able to join the trip to ORNL in Tennessee as part of his fellowship this summer. There, he got to experience the culture of a new laboratory and was finally able to perform the neutron scattering experiments that he’d spent the last summer studying through a computer program. He helped perform measurements on Weyl semimetals for his own project as well as other projects from Gaudet’s lab. 

Not everything went smoothly. Gaudet had time reserved to use three different machines at the lab, and technical issues sprung up on two of the machines—one wouldn’t cool down properly and another had a mechanical malfunction. So before getting experience running the experiments, Chen got a taste of troubleshooting equipment on a fixed schedule.

“Sitting at a computer looking at either generated data or gathered data, that's not actually like dealing with the machines breaking down, figuring out what can we do since we lost time because we had to fix the machines and things like that,” Chen said. “I think having done this once now, it's really helped me to understand a lot more how the instruments actually work and given me a better understanding of the process, which has helped me better contextualize and understand the data I have been working with.”

With those insights and new experimental data in hand, Chen is ready to move on to the next step of research: analyzing the data and sharing it with the rest of the research community. Chen’s initial analysis of the data he collected, as well as data from other experiments, validates his project from last summer.

“Patrick’s simulations led to several predictions, which could be verified with neutron scattering experiments,” Gaudet said. “He carried out such neutron experiments this summer at the Oak Ridge National Laboratory and successfully confirmed his predictions. The success of his project speaks to Patrick's motivation, curiosity, and ability for science, which I hope he will pursue further.”

During his last year at UMD, Chen plans to apply to graduate programs in physics and to continue working with Gaudet to write a paper on his research project to submit to an academic journal.

“I enjoyed the experience immensely, both for being able to gather the data and see all the stuff and do all the experiments as well as getting the chance to travel to the Smoky Mountains,” Chen said. “If I do end up continuing with condensed matter in grad school, neutron scattering is something that's probably pretty likely that I'll be using, so getting this experience now is really valuable.”

Story by Bailey Bedford