Cross Section Measurements on Gas Targets Relevant to the Production of the Positron Emitting Radionuclides ¹⁴O, ¹⁸F and ⁷⁶Br

Abstract

During the production of the ß⁺ emitting radionuclide ¹¹C via the ¹⁴N(p, α)-reaction on a N₂-gas target, appreciable quantities of ¹⁴O are formed as a side product via the ¹⁴N(p, n) reaction. Since its formation cross sections were not known well, we measured the data from the reaction threshold up to 20 MeV. The experimental cross section data for the production of the PET-isotope ¹⁸F via the most commonly used ¹⁸O(p, n)¹⁸F reaction were found to be rather weak or discrepant in some energy regions. Therefore the excitation function was remeasured from threshold up to 30 MeV using different solid and gas targets containing highly enriched ¹⁸O. The longer-lived ß⁺ emitter ⁷⁶Br is of some importance for investigating slow metabolic processes. The hithero unknown reaction ⁷⁸Kr(d, α)⁷⁶Br was investigated for the first time and its excitation function measured over the energy range up to 13 MeV by using the stacked gas cell technique.

Keywords:

• cross section
• excitation function
• nuclear reaction
• gas target, ¹¹C
• ¹⁴O
• ¹⁸F
• ⁷⁶Br
• ⁷⁸Kr
• positron emitter