Even at its present slow count-rate, CCI-2 can collect and process enough data to construct a 3-D movie of a line source of cesium-137 inside a thin pipe in a room, or a picture that distinguishes two small spheres of tin-113 placed close together. Improved electronics and algorithms, based on those used for the big research detector, GRETINA, will lead to higher resolution and faster response.
"The data used to construct these images allows them to be superposed on visible or x-ray images and viewed from any angle within 360 degrees, ideal for imaging during radiation therapy," Mihailescu says. "And by adding time discrimination, someday we'll be able to correlate the sources with moving objects."
The next iteration of the Compton imager will be tested with GRETINA, using beams from the 88-Inch Cyclotron. The results will contribute to basic science studies and may be especially pertinent to radioactive-beam facilities like those recently approved by DOE for the new Facility for Rare Isotope Beams (FRIB) to be built at Michigan State University.
"Imaging will help distinguish the radiation of interest in the experiment from the radioactive background caused by the beams," Vetter says, "and it will enable new concepts in measuring lifetimes of nuclear states that would be almost inaccessible by other means."
The improved gamma-ray imager will contribute to nuclear security techniques such as neutron activation and nuclear resonance fluorescence. In an age when nuclear materials in the wrong hands are a greater threat than nuclear war, when assured destruction is no deterrent, critical components in guarding against terrorist attack are detection, proliferation prevention, and safeguards.
But most important, the improved Compact Compton Imager will enable greater precision at lower risk for one of the most promising methods of radiation cancer
|Contact: Paul Preuss|
DOE/Lawrence Berkeley National Laboratory