Authorization and Inspection of Cyclotron Facilities Radiation Fields

Authorization and Inspection of Cyclotron Facilities 1) Existing radiation fields; 2) Description of the reactions; 3) Primary beam; 4) Secondary radiation; 5) Tertiary radiation; 6) Induced radioactivity.

Authorization and Inspection of Cyclotron Facilities Objective

Authorization and Inspection of Cyclotron Facilities

Projectile: protons or deuterons secondary: α, n, 2n, pn

Authorization and Inspection of Cyclotron Facilities –Beam of high-energy charged particles (p, d, a,...) –Highly ionizing and very short range (except in the vacuum of cyclotron and beam transport lines). –Easily absorbed. –Of local importance. No real shielding concern

Authorization and Inspection of Cyclotron Facilities –Results of the primary beam interactions with various materials (target, deflector, Dee, beam line,...) –It is characterized by its intensity, the angular distribution and energy spectrum. Neutrons –High penetration and relative biological effectiveness (RBE). Major concern with shielding.

Authorization and Inspection of Cyclotron Facilities

–Generated by the absorption of secondary particles. –Reaction of secondary neutrons capture. Gamma ray flux Very penetrating, moderate RBE. Significant impact on the shielding.

Authorization and Inspection of Cyclotron Facilities –Generated from reactions induced by the primary beam or secondary neutrons. –It is not relevant for the operation, but - It is the principal component of worker exposure. - Risk of internal and external contamination.

Authorization and Inspection of Cyclotron Facilities

–Elements like 152,154 Eu, 134 Cs y 60 Co, generated due to reactions with traces (ppm) of stable elements, existing in concrete: Predicting Long-Lived, Neutron- Induced Activation of Concrete in a Cyclotron Vault. L. R. Carroll. Carroll & Ramsey Associates.