Paper | Title | Page |
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TUPSA36 | Measurement of the Dose Rate and the Radiation Spectrum of the Interaction of 2 MeV Proton Beam with a Variety of Structural Materials | 113 |
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The paper presents the results of measurements of the spectrum and the radiation dose during irradiation of different construction materials with 2 MeV proton beam. There are shown the spectra of the induced activity of a number of materials and signals from the neutron detector. Based on the obtained results it is made the optimal choice of the target material, on which it is deposited a thin layer of lithium to generate epithermal neutrons used for boron neutron capture therapy of malignant tumors. Recommendations are given for materials desirable to use inside the high-energy beam transporting channel to reduce the dose of concomitant radiation. | ||
TUPSA37 | Measurement of the Spatial Distribution of Gamma Radiation at Tandem Accelerator with Vacuum Insulation | 116 |
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In BINP the source of epithermal neutrons for BNCT based on the tandem accelerator with vacuum insulation and a lithium target was created and operates. The paper presents the study of the spatial distribution of the X-ray emission produced by the interaction of accelerated electrons with the materials of construction of the accelerator. | ||
WEPSB16 | Studying of the Accompanying Charged Particles in the Tandem Accelerator with Vacuum Insulation | 189 |
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On the tandem accelerator with vacuum insulation in a steady long mode it was obtained 1.6 mA current of protons with 2 MeV energy. It was studied the one of the possible reasons of current limitation – the appearance of accompanying charged particles during acceleration of the ion beam. The paper presents and discusses the results of the accompanying beam measurement using a special detector. The detector registered an opposite positive current in the range of 80-170 mkA, which is directly dependent on vacuum conditions in the accelerator. Also it was measured the dependence of the dose rate on the total current in the accelerating gap. These measurements confirmed that injected H− beam ionizes residual and stripping gas mainly in the area before the first electrode and two proposals were made to minimize the accompanying current. | ||
FRCB01 | Problems and Prospects of the Tandem Accelerator with Vacuum Insulation | 465 |
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Funding: Ministry of Education and Science of Russia (project RFMEFI57614X0181) At BINP for development of boron neutron capture therapy it is proposed and constructed the tandem accelerator with vacuum insulation, which is characterized by rapid acceleration of charged particles. Problems of high-voltage strength gaps due to the large stored energy and strong electrostatic lens are solved. It is obtained a stationary 1.6 mA 2 MeV proton beam having 0.1% energy monochromaticity and 0.5% current stability. It is clarified, that further increase of the proton current in the stable mode without breakdowns is limited by the accompanying current in the high-voltage gaps. It is proposed to make vacuum conditions better in the input of the accelerator using additional cryopump, to modernize argon stripping target by its tilting or shifting and to use differential pumping inside the high-voltage electrode. Obtaining of the 3 mA 2.5 MeV proton beam will allow us to conduct boron neutron capture therapy. |
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Slides FRCB01 [0.815 MB] | |
WEPSB17 | Development of the Injector for Vacuum Insulated Tandem Accelerator | 191 |
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The Vacuum Insulated Tandem Accelerator is built at the Budker Institute of Nuclear Physics.* The accelerator is designed for development of the concept of accelerator-based boron neutron capture therapy of malignant tumors in the clinic.** In the accelerator the negative hydrogen ions are accelerated by the high voltage electrode potential to the half of required energy, and after conversion of the ions into protons by means of a gas stripping target the protons are accelerated again by the same potential to the full beam energy. A number of innovative ideas posited in the design make it possible to accelerate intense beams in a compact accelerator. Number of investigations revealed weak points of the accelerator injector: unnecessary beam stripping by the residual gas and complexity to improve the vacuum conditions, the influence of the stripping gas to the ion source operation stability. To ensure the beam parameters and reliability of the facility operation required for clinical applications, the new injector is designed based on the ion source with a current up to 15 mA, providing the possibility of preliminary beam acceleration upto 120-200 keV. The paper presents the design of the injector and the results of calculations performed.
*Aleynik V., Bashkirtsev A., et al. Applied Radiation and Isotopes 88 (2014) 177-179. **Bayanov B., Belov V., et al. Nuclear Instr. and Methods in Physics Research A 413/2-3 (1998) 397-426. |
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