DESIGN OF GAS TARGETS FOR THE PRODUCTION OF MEDICALLY USED RADIONUCLIDES WITH THE HELP OF MONTE-CARLO SIMULATION OF SMALL-ANGLE MULTIPLE-SCATTERING OF CHARGED-PARTICLES

Due to scattering of protons or deuterons in the target gas the radius of beams increases with increasing penetration depth of the particles . The increase depends on the kind of beam particle, the energy, the t arget gas and its temperature and pressure. A Monte-Carlo program was developed for simulation of multiple scattering. The initial beam has a particle distribution of variable sinusoidal shape behind the entran ce window and may be cut off by the simulation of a collimator. The be am distribution is calculated for up to 14 planes representing energy values of the particles due to a predefined range from one plane to th e next. The energy loss is calculated with the help of an integrated B ethe-Bloch routine. The distribution of the particles within the plane may be rearranged into profiles and transferred to a spreadsheet for further manipulation and graphical printout. Simulations are carried o ut for radionuclide production routes, commonly used for positron emis sion tomography (PET).