Preliminary experiment of the controllable Am-Be neutron source based on composite polymeric membrane

A controllable Am-Be neutron source was designed based on a hamburger structure including two Be pallets and a composite polymeric membrane carrying ²⁴¹Am. The composite polymeric membrane was made of polyvinylidene fluoride (PVDF) and polyvinyl alcohol (PVA). PVDF polymeric membrane was used as the base film to load the mixed Am(NO₃)₃-PVA solution, which was coated on the PVDF polymeric membrane. The thickness of two layers was both about 5 μm. The correlative calculations were performed using the Geant4 code. A piece of composite membrane loading ²⁴¹Am of 2.13 × 10⁶ Bq was placed in the middle of two Be pallets just like a hamburger. Neutrons were produced continuously until the composite membrane was separated from Be pallets. The neutron yield of the controllable hamburger neutron source was measured as 54 n/(10⁶α), which was 15.6 % lower than the calculation value. (author)