conducted to: 1) Characterize the target reactions with respect to neutron and gamma dose as measured through various thicknesses of shield material. 2) Characterize the accelerator... in the path of direct or stripped beam. 3) Evaluate a prototype neutron and gamma shield. A liquid-scintillator detector (NE213) with pulse-shape discrimination gave separate... to the data to yield dose rate and incident neutron spectra, which were then used for fluence and transport calculations. The shield measurements were in accord with prediction: The...

Article: "Predicting... Predicting Long-Lived, Neutron-Induced Activation of Concrete in a Cyclotron Vault L. R. Carroll Carroll & Ramsey Associates Abstract Many elements... in concrete can become activated by neutrons in a cyclotron vault, but only a few of the activation products are long-lived. The most prominent of these are Eu-152, Eu-154, Co-60, and Cs... of these cyclotrons are compact, low-energy (11-12 MeV proton energy) systems which come equipped with their own built-in radiation shielding. Others, however, are higher-energy (16-18...

construction techniques. In addition, polyethylene beads were placed between the wall studs to enhance neutron shielding. After pouring a concrete footer, the 6 ft. thick main shielding.... However, operation of high-current internal targets carries a substantial price in that the cyclotron itself is subject to an intense, damaging neutron flux which can eventually lead... to failure of major system components, as well as high-level, persistent, neutron-induced activation of the several tons of steel and copper comprising the main magnet. Neutron...

RDS-112 targets and which fits within the space constraints imposed by the closely-fitting cyclotron shield. download poster-presentation -- beamposter.pdf (2.5 Mbyte) The switcher... allows the user to utilize a fifth target -- i.e., to switch between two standard targets plus a beamstop mounted on a single beamline -- without opening the shield. The target... long aperture in a 6 mm thick Pb shield provides excellent spatial resolution with beta + (positron) or beta (-) emitters, but without the need for bulky lead shielding -- even...

"...Self-Shielded Accelerator for PET" Article: "Refurbishing and Recycling a Used Biomedical Cyclotron" Article: "Predicting Long-Lived, Neutron-Induced Activation of Concrete...- to long-lived radioisotopes, have to be installed in thick, concrete-walled shielding vaults or bunkers. Smaller accelerators used for the production of short-lived, neutron... Accelerator System Service and Technical Support New Accelerators and Accelerator System Upgrades RF System Design Radiation Shielding Radiation Detector Systems Application...