Evolution of Accelerator Based Neutron Source VITA

Budker Institute of Nuclear Physics has proposed, developed, and is operating accelerator based neutron source VITA, which includes an electrostatic tandem accelerator of charged particles of an original design (vacuum insulated tandem accelerator), a lithium neutron-generating target, and set of neutron beam shaping assemblies. The facility generates the stationary beam of protons or deuterons with the energy of up to 2.3 MeV and the current of up to 10 mA, the generation of a powerful neutron flux, and the formation of a beam of neutrons of various energy ranges, from cold to fast. The facility is actively used for the development of boron neutron capture therapy of malignant tumors (BNCT), radiation testing of promising materials, measuring the cross-section of nuclear reactions and some other applications. The second version of the accelerator based neutron source VITA-II features the presence of pre-acceleration to increase the proton energy, the use of a volumetric source of negative hydrogen ions instead of a surface plasma source to increase the proton beam current, and a decreased height of the installation due to the modernization of the high-voltage power supply and its connection to the accelerator. The accelerator based neutron source VITA-IIα was provided to the BNCT clinic in Xiamen (China) for the treatment of patients with the BNCT method. The second accelerator neutron source, VITA-IIβ, was manufactured to equip Blokhin National Medical Research Center of Oncology in Moscow to conduct clinical trials of the BNCT technique in the Russian Federation starting in 2025. Based on the experience gained, the third version of the accelerator based neutron source VITA-III and the compact accelerator based neutron source VITAmin are under development. The design of neutron sources, their features, parameters and applicability are presented and discussed.