The HANARO ex-core neutron irradiation facility was developed for various applications in the boron neutron capture therapy (BNCT) field, and its characteristics have been investigated. In order to obtain a sufficient thermal neutron flux with a low level contamination of fast neutrons and gamma-rays, a radiation filtering method is adopted. The radiation filter has been designed by using a silicon single crystal cooled by liquid nitrogen and a bismuth crystal. The installation of the main components of the irradiation facility and the irradiation room are finished. Experimental measurements of the neutron beam characteristics have been performed by using bare and cadmium covered gold foils and wires. The in-phantom neutron flux distribution was measured for a flux mapping inside the phantom. The gamma-ray dose was determined by using TLD-700 thermoluminescence dosimeters. The thermal and fast neutron fluxes and the gamma-ray dose were calculated by using the MCNP code, and they were compared with experimental data. The thermal neutron flux and Cd ratio which can be obtained at this facility are 1.49E9 n/cm2s and 152, respectively. The maximum neutron flux inside the phantom was measured to be 2.79E9 n/cm2s at a depth of 3 mm in the phantom. The two-dimensional in-phantom neutron flux distribution was determined, and the significant neutron irradiation was observed within 20 mm from the phantom surface. The gamma-ray dose rate for the free beam condition is expected to be about 80 cGy/hr. These experimental results are reasonably well supported by the calculated values of the facility design code. This HANARO thermal neutron facility can be used not only for a clinical trial but also for various basic irradiation researches of the BNCT field.
Previous measurements have shown large cross sections for the 11B(p,$α$)8Be reaction and K-shell ionization of boron from H+ ions. Past publications have shown that this reaction will likely increase the efficacy of proton therapy. This study investigates the size of boron particles for optimum treatment enhancement in proton therapy. Simulations of protons passing through varying sized boron particles were developed to compare energy outputs for alpha particles and low energy electrons. The results for the boron particle radius that produced the largest radiation output are presented in graph…
The proton boron fusion reaction, 11B(p, 3α), is investigated using MCNP6 to assess the viability for potential use in radiation therapy. The 11B(p, 3α) is theoretically desirable because it could combine the localized dose delivery protons exhibit (Bragg peak) with the creation of three high LET α particles that locally deposit energy in tumor regions. Simple simulations of a proton pencil beam incident upon a water phantom and a water phantom with an axial region also containing boron were modeled using MCNP6 in order to determine the extent of the impact boron had upon the calculated energy…
On the (un)effectiveness of Proton Boron Capture in Proton Therapy
我们目前的计算和模拟的作用，p+ $^{11}$ B $\to$ 3 $α$反应在质子治疗。这种反应最近被认为是负责肿瘤细胞的存活概率下降，当它们被低能质子照射时。然而，在所提出的硼载体（硼帽酸钠，Na $_{2}$ B $_{12}$ H $_{11}$ SH，简称BSH）的典型浓度水平下，即小于100 ppm，计算和蒙特卡罗模拟都表明，与该反应相关的剂量比由组织内的初级质子束递送的剂量低几个数量级。这些计算对质子硼捕获在增强质子治疗的治疗效果中发挥重要作用的说法提出了一些质疑，并建议应研究其他机制，以解释观察到的生存概率下降。
Neutron relative effectiveness factors in Boron Neutron Capture Therapy: estimation of their values from the secondary charged particles and evaluation of weighted kerma factors for a standard tissue
Quantum Mechanical Analysis of Neutron Wavefunction Overlap and Nuclear Interaction Probability with Carborane Cage ($^{10}$B10) in Boron Neutron Capture Therapy
Background and purpose: Accelerator-Based Boron Neutron Capture Therapy is a radiotherapy based on compact accelerator neutron sources requiring an epithermal neutron field for tumour irradiations. Neutrons of 10 keV are considered as the maximum optimised energy to treat deep-seated tumours. We investigated, by means of Monte Carlo simulations, the epithermal range from 10 eV to 10 keV in order to optimise the maximum epithermal neutron energy as a function of the tumour depth. Methods: A Snyder head phantom was simulated and mono-energetic neutrons with 4 different incident energies were use…
Boron Neutron Capture Therapy (BNCT) is a neutron radiotherapy used to treat tumours cells previously doping with Boron-10. This therapy requires an epithermal neutron beam for the treatment of deep tumours and a thermal beam for shallow ones. Thanks to recent high-current commercial accelerators, Accelerator-Based Neutron Sources (ABNS) are competitive option for providing therapeutic neutron beams in hospitals. In this work, the neutron field generated by the $^7$Li(p,n)$^7$Be reaction at $1950~$keV is studied as neutron source in ABNS, being measured by the Time-Of-Flight (TOF) technique at…
Distinct Radiobiological Responses to BNCT in SAS Oral Squamous Cell Carcinoma and MCF-7 Breast Cancer Cells
Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology（教育部辐射物理与技术重点实验室，核科学与技术研究所）；West China School of Basic Medical Sciences and Forensic Medicine（华西基础医学与法医学院）
Deep convolutional framelets for dose reconstruction in BNCT with Compton camera detector
Istituto Nazionale di Fisica Nucleare（国家核物理研究所）；Università degli Studi di Bari Aldo Moro（巴里阿尔多·莫罗大学）；Nanjing University of Science and Technology（南京理工大学）
We used the GEANT4 Monte Carlo MC Toolkit to simulate carbon ion beams incident on water, tissue, and bone, taking into account nuclear fragmentation reactions. Upon increasing the energy of the primary beam, the position of the Bragg-Peak transfers to a location deeper inside the phantom. For different materials, the peak is located at a shallower depth along the beam direction and becomes sharper with increasing electron density NZ. Subsequently, the generated depth dose of the Bragg curve is then benchmarked with experimental data from GSI in Germany. The results exhibit a reasonable correl…
