A potentially cost-saving and performance-enhancing new approach to fabricating superconducting radiofrequency (SRF) accelerating cavities has been demonstrated by the Institute for Superconducting Radiofrequency Science & Technology (ISRFST) at Jefferson Lab. Several single-cell niobium cavities were made from material sliced from large-grain niobium ingots, rather than fine-grain material melted from ingots and formed into sheets by the traditional process of forging, annealing, rolling and chemical etching. In tests carried out by ISRFST, these cavities performed extremely well.
Optical fluorescence and radiopharmaceutical imaging offer complementary ways of studying small animal physiology. A small, high resolution compact gamma camera has been developed and built at Jefferson Lab and integrated into a dual modality SPECT/optical small animal imaging system at the German Cancer Research Center (Heidelberg, Germany; Joerg Peter, PI). The key design features of the 10cm x 10cm field of view gamma camera are the use of a 2 x 2 array of flat panel position-sensitive photomultiplier tubes and a pixellated scintillation crystal array.
Silicon is perhaps one of the most important materials in our technological world, but its performance is always ultimately limited by impurities. Mitigation by impurity elimination is not possible, and theoretical understanding is very limited. Thus, these experiments, in which real-time dynamical evolution of excited impurity dynamics is measured, are of high fundamental as well as technological importance.
Jefferson Lab in collaboration with Case Western Reserve University (Dr. Zhenghong Lee) is developing a system that provides fused planar radiopharmaceutical imaging, planar x-ray imaging and planar bioluminescent/fluorescence imaging in a single apparatus for small animal imaging. Jefferson Lab developed a high resolution gamma camera based on a large position sensitive photomultiplier tube coupled to a pixellated NaI(Tl) scintillator array with individual crystal elements 1.3 mm x 1.3 mm x 6 mm in size and 0.2 mm septa between each element (1.5mm pixel step).
Hall D is the newest of Jefferson Lab’s four experimental halls. It is dedicated to the operation of a large-acceptance detector for experiments with a high-energy, polarized photon beam. The experiments are carried out by an international group of scientists called the GlueX collaboration.
New data from CLAS in Hall B probe the magnetic structure of the neutron at large momentum transfers, or small distances, with high precision. The magnetic form factor of the neutron, GMn, has been extracted from measurements of the ratio of quasi-elastic, electron-neutron to electron-proton scattering in deuterium over a Q2 range of 0.5-4.8 (GeV/c)2. The CLAS detector enabled the use of a combination of experimental techniques that allowed unprecedented precision to be achieved at Q2 ≥ 1 (GeV/c)2.
