Christopher Monahan will continue his quest to understand the structure of the proton through an Early Career Research Program award announced by the U.S. Department of Energy.

Monahan is an assistant professor in William & Mary’s Department of Physics. He is one of 83 early career scientists to be funded under the DOE program.

“Supporting America’s scientists and researchers early in their careers will ensure the U.S. remains at the forefront of scientific discovery and develops the solutions to our most pressing challenges,” said U.S. Secretary of Energy Jennifer M. Granholm in a DOE release. “The funding announced today will allow the recipients the freedom to find the answers to some of the most complex questions as they establish themselves as experts in their fields.”

Monahan’s focus is on the arrangement of the particles and interactions that make up the proton. He pointed out that the proton and the neutron, the proton’s companion in the atom’s nucleus, make up 95 percent of the mass in the visible universe.

The Standard Model of physics says that the proton is made up of three particles called quarks, held together by other particles known as gluons. It would be a mistake to picture the structure of the proton as a static, Lego-like quark-gluon arrangement.

“There are three quarks in each proton, and all of the time, each of these quarks is emitting a gluon that is being absorbed by another quark,” he explained.

Monahan said that it gets even wilder inside the proton: there are particle-antiparticle pairs continually popping in and out of existence. His DOE Early Career award will allow him to hire a postdoctoral researcher and attract some graduate students to work with him to nail down the interior structure of the proton.

He said they’ll be using supercomputing facilities to perform calculations based on proton/neutron structure data generated at the Thomas Jefferson National Accelerator Facility and the electron-ion collider planned for Brookhaven National Lab.

, Research Writer