Baldwin Awarded Department of Energy Fellowship To Work at Jefferson Lab

Carnegie Mellon University physics doctoral student Zach Baldwin is probing the glue that holds the most basic building blocks of matter together.

To help him advance his research, he will spend nine months working at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia with support from a Department of Energy Office of Science Graduate Student Research Program award. The Jefferson Lab, one 17 National Laboratories, houses the Continuous Electron Beam Accelerator Facility, which provides physicists with an unprecedented ability to study the basic building blocks of the visible universe: the nucleus of the atom and its protons, neutrons, quarks and gluons.

"I applied for the DOE SCGSR award as a way to propel my research further than I ever thought possible in this stage of my career," said Baldwin, who will return to Carnegie Mellon to complete is Ph.D.

Since arriving at Carnegie Mellon, Baldwin has been deeply involved with the Gluonic Excitation (GlueX) Experiment at the Jefferson Lab, studying and analyzing two significant decay processes that subatomic particles may undergo.

"These particle decay channels are crucial in the early efforts of the GlueX collaboration, as they can naturally manifest signals that could experimentally confirm the existence of what are known as exotic mesons," Baldwin said.

Exotic-hybrid mesons are subatomic particles that have been theorized but definitive experimental confirmation is still pending. By producing an exotic-hybrid meson, researchers aim to tease apart information about gluons — the carrier of the strong force, or the "glue," that binds a quark and anti-quark together in the meson within mesons and all matter. Exotic-hybrid mesons are of particular interest to the research group because the gluons could potentially exist in an excited state. Understanding this state could reveal information about how subatomic particles are built and why quarks are never found alone in our universe.

Identifying an exotic meson among numerous other particle interactions is somewhat like spotting a single ripple from a raindrop hitting a lake beset with many other types of waves from boats, animals and more during a rainstorm.

"Hadronic physicists like myself like to employ techniques known as amplitude — or partial wave — analyses, to analyze these tiny ripples. This sophisticated technique involves not just isolating these subtle signals from the surrounding noise and background, but also analyzing how these ripples interact with each other — how they merge, recoil, or cancel out, revealing the underlying dynamics of the particles involved," he said.

Baldwin will be on site during a data collection phase for GlueX. While he has traveled to the lab for a few days at a time in the past to take shifts during data collection phases, being there long term will provide an opportunity to see the work in a broader scope.

"I'll be able to be see first-hand with the staff scientists stationed at the lab everything that goes on behind the scenes," he said.

While at the Jefferson Lab, Baldwin will analyze experimental data from smashing highly energetic, polarized photons into protons at the accelerator deepen to deepen human's understanding of particles, which could make significant contributions to the ongoing search for exotic-hybrid mesons. He also will develop and test a new algorithm using AI and machine learning techniques to address the complex wave sets commonly encountered in high-energy physics experiments.

"Nuclear and particle physics is heavily evolving toward integration with AI and machine learning," Baldwin said. "Completing a project that incorporates this subject will pave the way for my future research career and goals, enabling me to explore more profoundly the exciting intersection of nuclear and particle physics with AI and machine learning."

Baldwin's advisor, Mellon College of Science Interim Dean Curtis Meyer, is a former leader and experiment spokesperson for the GlueX experiment. He has been involved in the experiment since its inception over 25 years ago.

Baldwin graduated from the College of William and Mary with a bachelor's degree in physics and mathematics. He has been very successful in finding opportunities like this to advance his scientific research and his career. He participated in The Open Science User Grid program in Madison, Wisconsin, and the International HPC School on Challenges in Computational Sciences in Athens, Greece and recently presented results from his research in Barcelona, Spain, at The 10th International Conference on Quarks and Nuclear Physics.

A first-generation college student from Appalachia, Baldwin said his path to nuclear and particle physics differs from his colleagues.

"My passion for physics was ignited by teachers whose dedication and willingness to go above and beyond nurtured my curiosity and guided my path," he said. An honors chemistry class inspired a passion for experiments. "I began seeking deeper answers about the universe than the class covered - specifically about the peculiar properties of atoms observed during our experiments."

A school librarian, upon learning of his interest in electrons and other particles acquired a copy of Brian Greene's "The Elegant Universe" for him.

"After reading this book (and the countless others like it afterwards), there was no going back, I knew I wanted to be a physicist," he said.