scholarly journals Monte Carlo modeling of a X-ray tube for superficial radiotherapy for evaluating the beam quality and the depth-dose distribution

2019 ◽  
Vol 1172 ◽  
pp. 012009
Author(s):  
Smolin Sergei ◽  
Butorov Ilya ◽  
Shevchenko Elena
Keyword(s):  
Monte Carlo ◽  
Dose Distribution ◽  
Beam Quality ◽  
Monte Carlo Modeling ◽  
X Ray ◽  
Depth Dose ◽  
Depth Dose Distribution

scholarly journals Evaluation of low energy X-ray depth dose distribution by gafchromic film for dosimetry in food irradiation

2020 ◽  
Vol 23 (2) ◽  
pp. First
Author(s):  
Ngoc Hoang Van ◽  
Huy Viet Le ◽  
Son An Nguyen ◽  
Kume Tamikazu
Keyword(s):  
Dose Distribution ◽  
Low Energy ◽  
Food Irradiation ◽  
Radiation Processing ◽  
X Ray ◽  
Gafchromic Film ◽  
Ion Chamber ◽  
Dose Profile ◽  
Depth Dose ◽  
Depth Dose Distribution

Introduction: Dosimetry is of crucial importance in radiation processing of food. Among others, plastic film has been widely used for dosimetry in radiation therapy since its density is quite similar to the equivalent biological materials. In this study, the depth dose distribution was estimated by using gafchromic film for the purpose of dosimetry in food irradiation. Experimental: The HD-V2 gafchromic dosimetry film was employed to measure the interested dose instead of ion chamber. A stack of 19 PMMA (polymethyl methacrylate) sheets interleaved with 20 pieces of gafchromic film was made. The phantom was applied in the low energy X-ray beams (maximum 100 keV) to obtain the depth dose profile. Results: A significant correlation between absorbed doses (D) and color level or optical density (O.D.) of irradiated dosimetry films was observed. The fitting function has the form of , where a, b, c are the parameters to be fitted. The depth dose distribution in the 30 mm thickness phantom was inferred from the calibration. Conclusion: The present method and the depth dose profile to be obtained are very meaningful in the processing of foodstuffs by radiation.

scholarly journals TWO-PARAMETRIC BEAM MODEL FOR DOSIMETRY OF THE PROCESS OF ELECTRON IRRADIATION OF MATERIALS WITH LOW DENSITY AND ATOMIC NUMBER

2021 ◽  
pp. 34-37
Author(s):  
V.T. Lazurik ◽  
V.M. Lazurik ◽  
G. Popov ◽  
Z. Zimek
Keyword(s):  
Monte Carlo ◽  
Electron Beam ◽  
Electron Irradiation ◽  
Dose Distribution ◽  
Parametric Model ◽  
Low Density ◽  
Dose Distributions ◽  
Depth Dose ◽  
Measurement Results ◽  
Depth Dose Distribution

The work is devoted to studying the possibility of using a two-parametric model of an electron beam to describe the depth distributions of the electron dose in materials with a low density and an effective atomic number. In this model, the parameters are determined by fitting the semi-empirical model (PFSEM-method) to the results of meas-urements of the depth-dose distribution in a dosimetric wedge. The depth-dose distributions in a birchwood wedge were measured at the Institute of Nuclear Chemistry and Technology in Warsaw, Poland. The parameters of the electron beam incident on the wedge were determined by the PFSEM method. The Monte Carlo simulations of the depth-dose distribution in the wedge for the process of electron irradiation, the characteristics of which are deter-mined by the PFSEM method, have been carried out. It is shown that there is a satisfactory agreement between the measurement results and the Monte Carlo simulation of the depth-dose distribution. The advantages of describing depth-dose distributions in a wedge based on a two-parametric model of an electron beam in comparison with tradi-tional methods of polynomial approximation of measurement results are discussed.

scholarly journals Comparison between the calculated and measured dose distributions for four beams of 6 MeV linac in a human-equivalent phantom

2006 ◽  
Vol 21 (2) ◽  
pp. 67-72
Author(s):  
Sonia Reda ◽  
Eman Massoud ◽  
Ibrahem Bashter ◽  
Esmat Amin
Keyword(s):  
Monte Carlo ◽  
Dose Distribution ◽  
Calculated Data ◽  
The Body ◽  
X Rays ◽  
Dose Distributions ◽  
Depth Dose ◽  
Thermoluminescence Dosimetry ◽  
Depth Dose Distribution ◽  
Good Agreement

Radiation dose distributions in various parts of the body are of importance in radiotherapy. Also, the percent depth dose at different body depths is an important parameter in radiation therapy applications. Monte Carlo simulation techniques are the most accurate methods for such purposes. Monte Carlo computer calculations of photon spectra and the dose ratios at surfaces and in some internal organs of a human equivalent phantom were performed. In the present paper, dose distributions in different organs during bladder radiotherapy by 6 MeV X-rays were measured using thermoluminescence dosimetry placed at different points in the human-phantom. The phantom was irradiated in exactly the same manner as in actual bladder radiotherapy. Four treatment fields were considered to maximize the dose at the center of the target and minimize it at non-target healthy organs. All experimental setup information was fed to the MCNP-4b code to calculate dose distributions at selected points inside the proposed phantom. Percent depth dose distribution was performed. Also, the absorbed dose as ratios relative to the original beam in the surrounding organs was calculated by MCNP-4b and measured by thermoluminescence dosimetry. Both measured and calculated data were compared. Results indicate good agreement between calculated and measured data inside the phantom. Comparison between MCNP-4b calculations and measurements of depth dose distribution indicated good agreement between both.

Experimental measurements and Monte Carlo modelling of the XSTRAHL 150 superficial X-ray therapy unit

2014 ◽  
Vol 14 (1) ◽  
pp. 43-55
Author(s):  
Fayez H. H. Al-Ghorabie
Keyword(s):  
Monte Carlo ◽  
Theoretical Calculations ◽  
Beam Quality ◽  
Patient Treatment ◽  
Experimental Measurements ◽  
Monte Carlo Code ◽  
X Ray ◽  
Percentage Depth Dose ◽  
Depth Dose ◽  
Good Agreement

AbstractBackgroundSuperficial X-ray therapy units are used for the treatment of certain types of skin cancer and some severe dermatological conditions. The performance assessment and beam characteristics of the superficial unit are very important to ensure accurate dose delivery during patient treatment. Both experimental measurements and Monte Carlo calculations can be used for this purpose.PurposeThis study aims to investigate whether it is possible to reproduce experimentally measured data for the XSTRAHL 150 superficial X-ray unit with simulations using the BEAMnrc Monte Carlo code.Materials and MethodsThe experimental procedure applied in this study included the following: experimental measurements of different X-ray spectra, half-value layers, percentage depth dose and beam profiles. Monte Carlo modelling of the XSTRAHL 150 unit was performed with the BEAMnrc code. The validity of the model was checked by comparing the theoretical calculations with experimental measurements.ResultsThere was good agreement (∼1%) between experimentally measured and simulated X-ray spectra. Results of half-value layers obtained from simulated and measured spectra showed that there was a maximum of 3·6% difference between BEAMnrc and measurements and a minimum of 2·3%. In addition, simulated percentage depth dose and profile curves have been compared against experimental measurements and show good agreement (within 2% for the depth dose curves and 3–5% for beam profile curves, depending on the applicator size).ConclusionThe results of this study provide information about particles’ interaction in different kilovoltage and filter combinations. This information is useful for X-ray tube design and development of new target/filter combinations to improve beam quality in superficial X-ray radiotherapy. The data presented here may provide a base for comparison and a reference for other or potential new users of the XSTRAHL 150 X-ray unit.

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