Top Physics Journal Features New Research by ODU Team

April 14, 2015

Larry Weinstein

Old Dominion physicist Larry Weinstein likes to describe scientific exploration into the atom's nucleus as child's play: "We study it like a 5-year-old. We hit it hard and we see what comes out."

Three months of smashing atoms around the clock at Jefferson Lab in Newport News - capping a study initiated 10 years ago - recently put Weinstein and dozens of colleagues back into the pages of the prestigious Physical Review Letters.

Their paper, "Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data" revealed deeper understanding of how electric charge is distributed in protons.

The study, led by Old Dominion University doctoral student Dasuni Adikaram, examined how electrons and anti-electrons (called positrons) scatter from protons. To do this, they first had to make a matter plus antimatter beam of electrons and positrons.

They found that, in some cases, positrons are slightly more likely than electrons to scatter from protons. This helps resolve a major problem with measurements of the proton.

Better still, Weinstein's group was the first of three collaborations around the world - the others were based in Russia and in Germany led by the Massachusetts Institute of Technology - to report the same findings despite using different testing methods.

"It was a 10-year project and we published ahead of the Russian group by two days," Weinstein said. "Until recently, we figured they were so far ahead of us, of course, they were going to publish first. But once it got down to the last few months and we realized they hadn't published, that's when we really kicked into high gear."

Getting there first and getting there correctly is a triumph for the University that Weinstein said is not taken for granted in scientific circles.

"We're the first University on the list," he said, noting over forty schools and laboratories contributed to the research. Fourteen faculty and students from Old Dominion took part. "What comes to us is an enhanced reputation for taking a hard project, doing it right and doing it quickly."

Weinstein said that, in a 10- year project, the "thrill of discovery" is his daily motivation.

"What practical application will come out of this research?" he said. "I don't know. Ask me in 20 years."