Feasibility Of Sealed D-T Neutron Generator Tube As Neutron Source For Boron Neutron Capture Therapy

Boron Neutron Capture Therapy(BNCT) is widely recognized worldwide as a cancer treatment and widely studied by lots of research institutes all over the world. The key to the success of BNCT is to find a stable neutron source. Currently, all the international clinical studies are based on the reactor neutron source; however, the reactor neutron source has the inevitable disadvantages, such as the high price, relatively poor safety and acceptability of the public. Therefore, my paper put forward to utilizing sealed neutron generator tube to serve as the neutron source for boron neutron capture therapy. Compared with the reactor, sealed neutron generator tube is safer, more economical and more acceptable by the public.According to the International Atomic Energy Agency(IAEA) recommend values, epithermal neutrons the energy of which range from 0.5 e V to 10 ke V are needed at the beam port of the facility. The energy of neutrons generated from the neutron tube is 14.1 Me V, which is far higher than that of epithermal neutron energy, so we need to use an assembly to reduce the energy. Such an assembly is called Beam Shaping Assembly(BSA). Because of the inelastic scattering in the BSA, the neutrons slow down and reduce neutron energy. Generally speaking, the neutron flux will reduce dramatically when the neutrons pass through the BSA, leading to increase of the treatment time. In order to solve this problem, proper multiplier materials should be used to increase the number of neutrons.This thesis mainly is finished by A General Monte Carlo Code for Neutron and Particle Transport program which is based on Monte Carlo method, using numerical analysis method. I chose to use software MCNP 4C version to design the assemblies. I took full advantage of the smaller size of sealed neutron generator tube and used several seal neutron tubes simultaneously to serve as the neutron source for Boron Neutron Capture Therapy. In addition, I also designed the Beam Shaping Assemblies, including the multiplier, the moderator and the reflector, for lioma, liver cancer and malignant melanoma skin. The epithermal neutron flux, the dose of fast neutron and gamma rays basically complied with the values recommended by IAEA. The results showed that sealed neutron generator tube could be used to serve as the neutron source for Boron Neutron Capture Therapy.