Sophisticated Physics Instruments Show ODU Pride
In a few years, when the $310 million energy upgrade at the Thomas Jefferson National Accelerator Facility in Newport News is completed and atom smashing experiments are probing deep into the building blocks of matter, the scientists working at the lab will know who built one of the sophisticated particle detectors installed at the facility.
That's because the team of scientists and technicians from the Old Dominion University Department of Physics building this "drift chamber" are labeling the instrument's components with what appears to be super-sized ODU bumper stickers.
"We had to have them specially made," said Lawrence Weinstein, the ODU professor of physics who is leading the project. "Even on a Hummer you wouldn't need one that big."
Indeed, Weinstein was standing in the Nuclear and Particle Physics High Bay laboratory of the ODU Physical Sciences Building pointing to one of the wedge-shaped components that will make up the drift chamber. It was labeled with an 8-foot-long "Old Dominion University," its letters in a collegiate font.
Tom Hartlove, the physics department lab specialist who manages the High Bay, said a local firm, Colley Avenue Copies and Graphics, agreed to laser ink the letters onto vinyl. "Each letter was made separately and I've had to place them myself. But I used to be a graphic designer, and that came in handy ."
On Thursday, July 12, the ODU team, together with the help of a large crane and a tractor-trailer with an air-cushioned ride, successfully moved the third drift chamber it has completed to Jefferson Lab. Two other components were moved earlier this year. The last two, like the last pieces of the pie, are under construction in the ODU High Bay's clean room, which promotes a dust-free environment to protect the sensitive equipment inside.
The total project is expected to cost about $2 million and should be completed by the end of the year, well ahead of schedule, Weinstein said.
Each wedge that will make up the drift chamber might be compared to a grand piano, except most pianos have only 300 strands of wire that are struck to create music and each detector component has 5,000 strings designed to detect particles flying from an atom smashing experiment. The gold-plated strings - with electricity running through them - will be sensitive enough to detect the subatomic debris from the experiments.
In Jefferson Lab parlance, the ODU team is building the Region 2 CLAS 12 Drift Chamber in Hall B of the facility. When the energy upgrade is completed in about two years, the mile-long accelerator, which cost $600 million to build a quarter century ago, will have double the energy for its electron beam, up from 6 billion electron volts (GeV) to 12 GeV.
The upgrade will provide more energetic collisions between electrons accelerated to near the speed of light and stationary subatomic targets. When the beam smashes into the experimental targets, detectors like the one ODU physicists are building will "catch" the fragments. By studying the speed, direction and energy of the scattered fragments, scientists can unveil the inner secrets of protons and neutrons. The greater the energy propelling the beam, the more detailed the information that can be expected.
Weinstein led the ODU team in the 1990s that designed and constructed part of the original CLAS detector at JLab.
He said the components have been moved successfully so far, without a single string breaking. Jefferson Lab is about 25 miles from the ODU campus.
For each moves, a component is wrapped to keep out dust, then wheeled out of the High Bay on a specially built wagon. The component and wagon together are hoisted onto the truck bed, which is equipped with shock-absorbing cradles for the wagon wheels. Then an aerodynamically specific plywood crate is fitted over the component and the crate covered by huge tarps.
Weinstein, who conducts experiments at Jefferson Lab, is working on the project with other physics faculty members Gail Dodge, Stephen Bueltmann and Sebastian Kuhn. The project team members are among 14 ODU professors in nuclear and accelerator physics who are affiliated with the lab.
Although Hartlove manages the day-to-day operations of the lab, post-doctoral researcher Robert Bennett oversees the performance testing of all drift chamber components before they can be shipped to Jefferson Lab. "He is the best post doc I've ever worked with," Hartlove said.
The ODU Experimental Nuclear Physics Group is one of the largest and most experienced research groups working at Jefferson Lab. In addition to building major detector systems for both the original Jefferson Lab complement and the new upgrade, they are also leaders on a wide variety of experimental programs to explore the nature of matter. They typically lead experiments that use about 10 percent of Jefferson Lab's beam time (experimental time) each year. Applied proportionately, that amounts to about $10 million of the $100 million in research that Jefferson Lab performs each year.