Browsing by Author "Arasoglu, A."

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The Comparison of Absorbed Dose Measurements for Water and Artificial Body Fluid
(Ijrr-iranian Journal Radiation Res, 2012) Cakir, T.; Gur, A.; Arasoglu, A.
Background: Advances in radiation dosimetry concepts and the development of primary measurement standards based on absorbed dose to water over the last decades offer the possibility to calibrate ionisation chambers directly in terms of absorbed dose to water. The aim of this study is the investigation on utility of artificial body fluid (ABF) instead of water by comparing dosimetric measurements for radiotherapy between water and ABF which is more close to human tissue. Materials and Methods: The measurements were done using Co-60 gamma source with a radiation field sizes of 5 x 5, 10 x 10, 15 x 15, 20 x 20 and 25 x 25 cm(2) at PTW Freiburg MP3 water phantom front surface. The comparisons of the dose measurements were obtained by using IAEA TRS-398 dosimetry protocols and Mephysto mc(2) dose analyzer program. Percent depth dose (PDD), dose profiles and penumbras are compared for water and ABF. Results: When the results of the PDD for water and ABF were compared, the maximum difference was observed in big field sizes. The difference in penumbras was found 2.3 mm averagely for depth of maximum dose (d(max)). In addition same differences were observed between water and ABF when the dose profiles were compared. It is found that PDD values taken for water are good agreed with PDD values published in British Journal of Radiology (BJR) Supplement 25. Conclusion: Since the ABF is more equivalent to human tissue than water, it is suggested that advanced dosimetric studies should be performed with ABF instead of water. Iran. J. Radiat. Res., 2012; 10(3-4): 157-164
Investigation of Some Structural Fusion Materials for (N, 2n) Reactions Up To 40 Mev
(Springer, 2010) Arasoglu, A.; Tel, E.
The knowledge of (n, 2n) cross section is very important and necessary in the reactor technology since a significant portion of the fission neutron spectrum lies above the threshold of (n, 2n) reaction for the most of the reactor materials. The (n, 2n) cross section is neutron multiplier reaction in fusion reactor design. Therefore, (n, 2n) reactions of the selected blanket materials can play a key role for multiplying neutrons in reactor environment. In this study, for some structural fusion materials (n, 2n) reactions such as (27)Al(n, 2n)(26)Al, (51)V(n, 2n)(50)V, (52)Cr(n, 2n)(51)Cr, (55)Mn(n, 2n)(54)Mn, (56)Fe(n, 2n)(55)Fe and (58)Ni (n, 2n)(57)Ni have been carried out up to 40 MeV incident neutron energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. Also in the present work, the (n, 2n) reaction cross-sections have calculated by using evaluated empirical formulas developed by Tel et al. at 14-15 MeV energy. The calculated results are discussed and compared with the experimental data taken from EXFOR database.
Triton Emission Spectra in Some Target Nuclei Irradiated by Ultra-Fast Neutrons
(Springer, 2010) Tel, E.; Kaplan, A.; Aydin, A.; Buyukuslu, H.; Demirkol, I.; Arasoglu, A.
High-current proton accelerator technologies make use of spallation neutrons produced in (p,xn) and (n,xn) nuclear reactions on high-Z targets. The produced neutrons are moderated by heavy water. These moderated neutrons are subsequently captured on (3)He to produce tritium via the (n,p) reaction. Tritium self-sufficiency must be maintained for a commercial power plant. So, working out the systematics of (n,t) reaction cross sections and triton emission differential data are important for the given reaction taking place on various nuclei at different energies. In this study, triton emission spectra by using ultra-fast neutrons (incident neutron energy > 50 MeV), the (n,xt) reactions for some target nuclei as (16)O, (27)Al, (56)Fe, (59)Co, (208)Pb and (209)Bi have been investigated. In the calculations, the pre-equilibrium and equilibrium effects have been used. The calculated results have been compared with the experimental data taken from the literature.