Budker Institute of Nuclear Physics

The particle identification system ASHIPH (Aerogel, SHIfter, PHotomultiplier) has been working in the KEDR experiment at the VEPP-4M e⁺e^- collider (Budker INP, Novosibirsk), without interventions and upgrade, since 2014.The system consists of 160 aerogel Cherenkov counters containing aerogel with refractive index of 1.05.The ASHIPH system provides π/K separation in the momentum range from 0.6 to 1.5 GeV/c.The status of the system is presented.The long-term stability of aerogel counters in the KEDR experiment is studied.The use of the ASHIPH system in physics anal. is presented as well.

An intense epithermal neutron flux is necessary for boron neutron capture therapy (BNCT), a promising technique for the treatment of malignant tumors. The epithermal neutron flux is an essential characteristic of the BNCT neutron beam, and its measurement is directly related to the reliability of the treatment planning system. Such a tool could be a cylindrical activation detector using ⁷¹Ga (n,γ)⁷²Ga reaction. In the detector, the activation material is positioned in the geometrical center of a cylinder moderator covered with cadmium foil. Two different teams of researchers calculated the sensitivities of detectors of the same size, but with different moderators which differ by a factor of 1.6. In this work, the effect of the moderator material on the sensitivity of the detector was experimentally studied.

Boron neutron capture therapy, a promising method for treating malignant tumors, requires accelerator based sources of neutrons in the epithermal energy range.One of the popular charged particle accelerators is an electrostatic tandem accelerator of an original design called Vacuum Insulated Tandem Accelerator (VITA).The paper presents the results of phase portrait measurements of an ion beam conducted at the Budker Institute of Nuclear Physics exptl. facility and at oncol. clinics equipped with pre-acceleration.The advantages and disadvantages of using pre-acceleration are shown.A proposal is made to improve VITA, confirmed by the results of numerical simulation of ion beam transportation and acceleration.