scholarly journals An Optimization Design of Collimator in The Thermal Column of Kartini Reactor For BNCT

2017 ◽  
Vol 2 (2) ◽  
pp. 54
Author(s):  
M. Ibnu Khaldun ◽  
Andang Widi Harto ◽  
Yohannes Sardjono

Studies were carried out to design a collimator which results in epithermal neutron beam for in vivo experiment of Boron Neutron Capture Therapy (BNCT) at the Kartini Research Reactor by means of Monte Carlo N-Particle (MCNP) codes. Reactor within 100 kW of thermal power was used as the neutron source. All materials used were varied in size, according to the value of mean free path for each material. MCNP simulations indicated that by using 6 cm thick of Natural Nickel as collimator wall, 65 cm thick of Al as moderator, 3 cm thick of Ni-60 as filter, 6 cm thick of Bi as γ-ray shielding, 3.5 cm thick of Li<sub>2</sub>CO<sub>3</sub>-polyethilene, with 2 cm aperture diameter. Epithermal neutron beam with maximum flux of 6.60 x 10<sup>8</sup>n.cm<sup>-2</sup>.s<sup>-1</sup> could be produced. The beam has minimum fast neutron and γ-ray components of, respectively, 1.82 x 10<sup>-13</sup>Gy.cm<sup>2</sup>.n<sup>-1</sup> and 1.70 x 10<sup>-13</sup> Gy.cm<sup>2</sup>.n<sup>-1</sup>, minimum thermal neutron per epithermal neutron ratio of 0.041, and maximum directionality of 2,12. It did not fully pass the IAEA’s criteria, since the epithermal neutron flux was below the recommended value, 1.0 x 10<sup>9</sup> n.cm<sup>-2</sup>.s<sup>-1</sup>. Nonetheless, it was still usable with epithermal neutron flux exceeding 5.0 x 10<sup>8</sup> n.cm<sup>-2</sup>.s<sup>-1</sup>. it is still feasible for BNCT in vivo experiment.

2020 ◽  
Author(s):  
Ian Postuma ◽  
Sara Gonzalez ◽  
Maria Herrera ◽  
Lucas Provenzano ◽  
Michele Ferrarini ◽  
...  

Abstract The standard of neutron beam quality for Boron Neutron Capture Therapy (BNCT) of deep-seated tumours is currently defined by its physical characteristics in air: the epithermal neutron flux, the ratio of thermal and epithermal neutron flux, the fast neutron and photon dose contamination, and the beam collimation. Traditionally, the beam design consists in tailoring a Beam Shaping Assembly (BSA) able to deliver a neutron beam with the recommended values of these figures of merit (FOMs). This work investigated the possibility to produce an epithermal neutron beam able to guarantee the best clinical performance for deep-seated tumours, starting from a 5 MeV, 30 mA proton beam coupled to a beryllium target. Different Beam Shaping Assemblies were designed using those physical FOMs which, however, were not enough to establish a clear ranking of the different beams, nor to describe their clinical relevance. To go beyond this traditional approach, beams were then evaluated employing new criteria based on the dose distributions obtained in-phantom and on the calculation of the Uncomplicated Tumour Control Probability (UTCP). Such radiobiological FOM allows establishing the therapeutic potential of the beams. Moreover, we included the concept of suitability as a criterion to select the safest BSA design, calculating the in-patient out-of-beam dosimetry. The clinical relevance of the selected beam was finally tested in the treatment planning of a clinical case treated at the FiR 1 beam in Finland, where several patients have safely and successfully received BNCT in the last years. Despite the selected beam does not comply with all the standard physical recommendations, it shows a therapeutic potential comparable and even better than that of FiR 1. This confirms that establishing the performance of a beam cannot rely only on its physical characteristics, but requires additional criteria able to predict the clinical outcome of a BNCT treatment.


Author(s):  
Bilal Odin ◽  
Gede Bayu Suparta ◽  
Arief Hermanto ◽  
Dwi Satya Palupi ◽  
Yohannes Sardjono ◽  
...  

A simulation study on the Double-layer Beam Shaping Assembly (DBSA) system has been carried out. This study used fast neutron beam resulting from reactions of 30 MeV protons with beryllium target. The MCNPX code was utilized to design the DBSA and the phantom as well as to calculate neutron flux on the phantom. The distribution of epithermal neutron flux and gamma in the DBSA and phantom were computed using the PHITS code. The spectrum of radiation beams generated by the DBSA shows the characteristics that the typical epithermal neutron flux of 1.0 x109 n/(cm2.s), the ratio of epithermal to the thermal and fast neutron flux of 344 and 85, respectively and the ratio of gamma dose to the epithermal neutron flux of 1.82 x 10-13 Gy.cm2. The test of epithermal neutron beams irradiation on the water phantom shows that epithermal neutrons are thermalized and penetrate the phantom up to 12 cm in depth. The maximum value of neutron flux is 1.1 x 109 n/(cm2.s) at a depth of 2 cm in phantom.  


1967 ◽  
Vol 29 (2) ◽  
pp. 299-302 ◽  
Author(s):  
K. B. Cady ◽  
G. J. Kirouac ◽  
J. J. McInerney

2016 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Yohannes Sardjono ◽  
Susilo Widodo ◽  
Irhas Irhas ◽  
Hilmi Tantawy

Boron Neutron Capture Therapy (BNCT) is an advanced form of radiotherapy technique that is potentially superior to all conventional techniques for cancer treatment, as it is targeted at killing individual cancerous cells with minimal damage to surrounding healthy cells. After decades of development, BNCT has reached clinical-trial stages in several countries, mainly for treating challenging cancers such as malignant brain tumors. The Indonesian consortium of BNCT already developed of the design BNCT for many cases of type cancers using many neutron sources. The main objective of the Indonesian consortium BNCT are the development of BNCT technology package which consists of a non nuclear reactor neutron source based on cyclotron and compact neutron generator technique, advanced boron-carrying pharmaceutical, and user-friendly treatment platform with automatic operation and feedback system as well as commercialization of the BNCT though franchised network of BNCT clinics worldwide. The Indonesian consortium BNCT will offering to participate in Boron carrier pharmaceuticals development and testing, development of cyclotron and compact neutron generators and provision of neutrons from the 100 kW Kartini Research Reactor to guide and to validate compact neutron generator development. Studies were carried out to design a collimator which results in epithermal neutron beam for Boron Neutron Capture Therapy (BNCT) at the Kartini Research Reactor by means of Monte Carlo N-Particle 5 (MCNP5) codes. Reactor within 100 kW of output thermal power was used as the neutron source. The design criteria were based on the IAEA’s recommendation. All materials used were varied in size, according to the value of mean free path for each. Monte Carlo simulations indicated that by using 5 cm thick of Ni as collimator wall, 60 cm thick of Al as moderator, 15 cm thick of 60Ni as filter, 1,5 cm thick of Bi as "-ray shielding, 3 cm thick of 6Li2CO3-polyethylene as beam delimiter, with 3-5 cm varied aperture size, epithermal neutron beam with minimum flux of 7,8 x 108 n.cm-2.s-1, maximum fast neutron and "-ray components of, respectively, 1,9 x 10-13 Gy.cm2.n-1 and 1,8 x 10-13 Gy.cm2.n-1, maximum thermal neutron per epithermal neutron ratio of 0,009, and beam minimum directionality of 0,72, could be produced. The beam did not fully pass the IAEA’s criteria, since the epithermal neutron flux was still below the recommended value, 1,0 x 109 n.cm-2.s-1. Nonetheless, it was still usable with epithermal neutron flux exceeded 5 x 108 n.cm-2.s-1. When this collimator was surrounded by 8 cm thick of graphite, the characteristics of the beam became better that it passed all IAEA’s criteria with epithermal neutron flux up to 1,7 x 109 n.cm-2.s-1. it is still feasible for BNCT in vivo experiment and study of many cases cancer type i.e.; liver and lung curcinoma. In this case, thermal neutron produced by model of Collimated Thermal Column Kartini Research Nuclear Reactor, Yogyakarta. Sodium boroncaptate (BSH) was used as in this research. BSH had effected in liver for radiation quality factor as 0.8 in health tissue and 2.5 in cancer tissue. Modelling organ and source used liver organ who contain of cancer tissue and research reactor. Variation of boron concentration was 20, 25, 30, 35, 40, 45, and 47 $g/g cancer. Output of MCNP calculation were neutron scattering dose, gamma ray dose and neutron flux from reactor. Given the advantages of low density owned by lungs, hence BNCT is a solid option that can be utilized to eradicate the cell cancer in lungs. Modelling organ and neutron source for lung carcinoma was used Compact Neutron Generator (CNG) by deuterium-tritium which was used is boronophenylalanine (BPA). The concentration of boron-10 compound was varied in the study; i.e. the variations were 20; 25; 30; 35; 40 and 45 μg.g-1 cancer tissues. Ideally, the primary dose which is solemnly expected to contribute in the therapy is alpha dose, but the secondary dose; i.e. neutron scattering dose, proton dose and gamma dose that are caused due to the interaction of thermal neutron with the spectra of tissue can not be simply omitted. Thus, the desired output of MCNPX; i.e. tally, were thermal and epithermal neutron flux, neutron and photon dose. The liver study variation of boron concentration result dose rate to every variation were0,042; 0,050; 0,058; 0,067; 0,074; 0,082; 0,085 Gy/sec. Irradiation time who need to every concentration were 1194,687 sec (19 min 54 sec);999,645 sec (16 min 39 sec); 858,746 sec (14 min 19 sec); 743,810 sec (12 min 24 sec); 675,156 sec (11 min 15 sec); 608,480 sec (10 min 8 sec); 585,807sec (9 min 45 sec). The lung carcinoma study variations of boron-10 concentration in tissue resulted in the dose rate of each variables respectively were 0.003145, 0.003657, 0.00359, 0.00385, 0.00438 and 0.00476 Gy.sec-1 . The irradiated time needed for therapy for each variables respectively were 375.34, 357.55, 287.58, 284.95, 237.84 and 219.84 minutes.


2021 ◽  
Vol 10 (1) ◽  
pp. 11-20
Author(s):  
Tho Nguyen Thi ◽  
Anh Tran Tuan ◽  
Cuong Trinh Van ◽  
Doanh Ho Van ◽  
Duong Tran Quoc ◽  
...  

The accuracy of elements concentration determination using the k0-standardization method directly depends on irradiation and measurement parameters including Non-1/E epithermal neutron flux distribution shape α (ϕ epi ≈1/E1+α ) , thermal-to-epithermal neutron flux ratio f, efficiency ε, peak area… In the case of the irradiation position at the rotary rack of the Dalat Nuclear Research Reactor (DNRR), the difference of thermal neutron flux between the bottom (3.54x1012 n.cm-2.s-1) and the top (1.93x1012 n.cm-2.s-1) of the 15 cm aluminum container is up to 45%. Therefore, it is necessary to accurately determine above-mentioned parameters in the sample irradiation position. The present paper deals with the determination of the distribution of thermal neutron flux along the sample irradiation container by using 0.1% Au–Al wire activation technique. The thermal neutron flux was then used to calculate the concentration of elements in the Standard Reference Material 2711a and SMELS type III using k0-INAA method at different positions in the container. The obtained results with the neutron flux correction were found to be in good agreement with the certified values. In conclusion, the proposed technique can be applied for activation analyses without sandwiching flux monitors between samples during irradiations.


Atomic Energy ◽  
2017 ◽  
Vol 121 (6) ◽  
pp. 389-396 ◽  
Author(s):  
O. B. Samoilov ◽  
V. I. Alekseev ◽  
V. Yu. Galitskikh ◽  
A. V. Belin ◽  
A. N. Zaglyadnov ◽  
...  

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