Simulation of dose distribution and secondary particle production in proton therapy of brain tumor

AimThe aim of this study is simulation of the proton depth-dose distribution and dose evaluation of secondary particles in proton therapy of brain tumor using the GEANT4 and FLUKA Monte Carlo codes.BackgroundProton therapy is a treatment method for variety of tumors such as brain tumor. The most important feature of high energy proton beams is the energy deposition as a Bragg curve and the possibility of creating the spread out Bragg peak (SOBP) for full coverage of the tumor.Materials and methodsA spherical tumor with the radius of 1 cm in the brain is considered. A SNYDER head phantom has been irradiated with 30−130 MeV proton beam energy. A PMMA modulator wheel is used for covering the tumor. The simulations are performed using the GEANT4 and FLUKA codes.ResultsUsing a modulator wheel, the Spread Out Bragg Peak longitudinally and laterally covers the tumor. Flux and absorbed dose of secondary particles produced by nuclear interactions of protons with elements in the head are considerably small compared to protons.ConclusionsUsing 76.85 MeV proton beam and a modulator wheel, the tumor can be treated accurately in the 3-D, so that the distribution of proton dose in the surrounding tissues is very low. The results show that more than 99% of the total dose of secondary particles and protons is absorbed in the tumor

Measurement of 100Mo (n, 2n) 99Mo reaction cross section and covariance analysis using extended unscented transformation technique at the incident neutron energy of 13.9 MeV

In this paper, the measurement and covariance analysis of the cross section of 100Mo (n, 2n) 99Mo reaction, with the 197Au (n, 2n)196 Au reaction being used as the monitor, at the incident neutron energy of 13.9 MeV is reported. The 3H (d, n) 4He nuclear reaction is used as the neutron source. The experiment was performed at the Purnima neutron facility, BARC. The method of activation with off-line -ray spectrometry is used. The covariance analysis of the 100Mo (n, 2n) 99Mo reaction is also performed, for the first time, using the extended unscented transformation (EUT) technique1, which is an extension of unscented transformation (UT) technique2, for the determination of partial uncertainties arising due to attributes in combination with the micro-correlation technique of Geraldo and Smith3. The present results obtained for 100Mo (n, 2n) 99Mo reaction cross section are found to be in good agreement with EXFOR data and the theoretically calculated value using the TALYS 1. 8 code. Comparisons with the data in the available basic evaluated nuclear data libraries, such as ENDF/B-VIII.0, JEFF-3.3, JENDL-4.0, ROSFOND-2010, CENDL-3.1 and TENDL 2017 are also presented and discussed

Measurement of 100Mo (n, 2n) 99Mo reaction cross section and covariance analysis using extended unscented transformation technique at the incident neutron energy of 13.9 MeV

351-357In this paper, the measurement and covariance analysis of the cross section of 100Mo (n, 2n) 99Mo reaction, with the 197Au (n, 2n)196 Au reaction being used as the monitor, at the incident neutron energy of 13.9 MeV is reported. The 3H (d, n) 4He nuclear reaction is used as the neutron source. The experiment was performed at the Purnima neutron facility, BARC. The method of activation with off-line -ray spectrometry is used. The covariance analysis of the 100Mo (n, 2n) 99Mo reaction is also performed, for the first time, using the extended unscented transformation (EUT) technique1, which is an extension of unscented transformation (UT) technique2, for the determination of partial uncertainties arising due to attributes in combination with the micro-correlation technique of Geraldo and Smith3. The present results obtained for 100Mo (n, 2n) 99Mo reaction cross section are found to be in good agreement with EXFOR data and the theoretically calculated value using the TALYS 1. 8 code. Comparisons with the data in the available basic evaluated nuclear data libraries, such as ENDF/B-VIII.0, JEFF-3.3, JENDL-4.0, ROSFOND-2010, CENDL-3.1 and TENDL 2017 are also presented and discussed

Measurement of 67Zn(n,p) 67Cu, 64Zn(n,2n) 63Zn, 89Y(n,&gamma,) 90mY and 89Y(n,2n) 88Y Reaction Cross Sections at the Neutron Energy of 14.54 MeV with Covariance Analysis

The 67Zn(n,p)67Cu, 64Zn(n,2n)63Zn, 89Y(n,&gamma,)90mY and 89Y(n,2n)88Y reaction cross sections relative to the 197Au(n,2n)196Au monitor reaction have been determined at the neutron energy of 14.54 ,± ,0.002 MeV by using the method of activation and off-line &gamma,-ray spectrometry. The neutron energy used was obtained from the 3H(d,n)4He reaction. The covariance analysis was performed by taking the uncertainties arising in various attributes and the correlations between those attributes. The analyzed results from the present measurement were compared with the literature data and evaluated data of various libraries like ENDF/B-VIII, JEFF-3.3, JENDL-4.0 and ROSFOND-2010 libraries as well as with the calculated values based on TALYS-1.9 code

Measurement of 67Zn(n,p) 67Cu, 64Zn(n,2n) 63Zn, 89Y(n,&gamma,) 90mY and 89Y(n,2n) 88Y Reaction Cross Sections at the Neutron Energy of 14.54 MeV with Covariance Analysis

The 67Zn(n,p)67Cu, 64Zn(n,2n)63Zn, 89Y(n,&gamma,)90mY and 89Y(n,2n)88Y reaction cross sections relative to the 197Au(n,2n)196Au monitor reaction have been determined at the neutron energy of 14.54 ,± ,0.002 MeV by using the method of activation and off-line &gamma,-ray spectrometry. The neutron energy used was obtained from the 3H(d,n)4He reaction. The covariance analysis was performed by taking the uncertainties arising in various attributes and the correlations between those attributes. The analyzed results from the present measurement were compared with the literature data and evaluated data of various libraries like ENDF/B-VIII, JEFF-3.3, JENDL-4.0 and ROSFOND-2010 libraries as well as with the calculated values based on TALYS-1.9 code

93Nb(n,2n) 92mNb, 93Nb(n,α) 90mY and 92Mo(n,p) 92mNb Reactions at 14.78 MeV and Covariance Analysis

The cross sections for the 93Nb(n,2n)92mNb, 93Nb(n,α)90mY and the 92Mo(n,p)92mNb reactions have been measured with respect to the 197Au(n,2n)196Au monitor reaction at the incident neutron energy of 14.78 ± 0.19 MeV by employing methods of activation and off-line γ-ray spectrometry. The covariance analysis was carried out by taking into consideration of partial uncertainties in different attributes and correlation among the attributes. The present data have been compared with the literature data available in EXFOR, evaluated data of different libraries and theoretical values based on TALYS-1.8 code

IAEA coordinated research project on nuclear data for charged-particle monitor reactions and medical isotope production

An IAEA coordinated research project was launched in December 2012 to establish and improve the nuclear data required to characterise charged-particle monitor reactions and extend data for medical radionuclide production. An international team was assembled to undertake work addressing the requirements for more accurate cross-section data over a wide range of targets and projectiles, undertaken in conjunction with a limited number of measurements and more extensive evaluations of the decay data of specific radionuclides. These studies are nearing completion, and are briefly described below

Measurement of cross sections and isomeric yield ratios for

The flux weighted average cross sections and the isomeric yield ratios of 110m, gIn, 111m, gIn and 112m, gIn in the natIn($\gamma$,xn) 112-110In reactions with the bremsstrahlung end-point energies of 65, 70 and 75 MeV have been determined by activation and off-line $\gamma$-ray spectrometric technique using the 100 MeV electron linac at Pohang accelerator laboratory, Korea. It was found that the natIn($\gamma$,xn) 112-110In reaction cross sections increase very fast from the threshold energy to a certain value of the bremsstrahlung energy, where the other reaction channel opens. After a certain energy, it remains constant because the cross section of the other reaction channel starts to increase. This indicates the partition of the excitation energy in different reaction channles. The isomeric yield ratios of 110m, gIn, 111m, gIn and 112m, gIn in the natIn($\gamma$,xn) reactions decrease very fast with the bemsstrahlung end-point energy from the threshold value to 15-30 MeV due to the giant dipole resonance (GDR) effect. Above that, the isomeric yield ratios increase slowly with the bremsstrahlung energy due to the increase of excitation energy

Measurement of reaction cross-sections for 89Y at average neutron energies of 7.24-24.83 MeV

We measured neutron-induced reaction cross-sections for 89Y(n,γ)90mY and 89Y(n,α)86Rb reactions with the average neutron energy region from 7.45 to 24.83 MeV by an activation and off-line γ-ray spectrometric technique using the MC-50 Cyclotron at Korea Institute of Radiological and Medical Sciences. The neutron-induced reaction cross-sections of 89Y as a function of neutron energy were taken from the TENDL-2013 library. The flux-weighted average cross-sections for 89Y(n,γ)90mY and 89Y(n,α)86Rb reactions were calculated from the TENDL-2013 values based on mono-energetic neutron and by using the neutron energy spectrum from MCNPX 2.6.0 code. The present results are compared with the flux-weighted values of TENDL-2013 and are found to be in good agreemen

Measurement of reaction cross-sections for

We measured neutron-induced reaction cross-sections for 89Y(n,γ)90mY and 89Y(n,α)86Rb reactions with the average neutron energy region from 7.45 to 24.83 MeV by an activation and off-line γ-ray spectrometric technique using the MC-50 Cyclotron at Korea Institute of Radiological and Medical Sciences. The neutron-induced reaction cross-sections of 89Y as a function of neutron energy were taken from the TENDL-2013 library. The flux-weighted average cross-sections for 89Y(n,γ)90mY and 89Y(n,α)86Rb reactions were calculated from the TENDL-2013 values based on mono-energetic neutron and by using the neutron energy spectrum from MCNPX 2.6.0 code. The present results are compared with the flux-weighted values of TENDL-2013 and are found to be in good agreemen