Experimental, theoretical, and biological investigations on radiation shielding parameters of boron-doped cerrobend alloys

ABSTRACT

This experimental and theoretical study investigated the efficiency of radiation absorption by Cerrobend alloy with varying concentrations of B₄C compound. Four blocks were prepared containing 0%, 5%, 10%, and 15% B₄C, respectively. The study examined radiation attenuation characteristics, including the mass attenuation coefficient, linear attenuation coefficient, half-value layer thickness, and mean free path, as well as radiobiological consequences for each block, using photon energies of 6 and 15 MeV. It has been observed that the rise in the quantity of B₄C leads to a decrease in the material’s ability to absorb photons. The highest mass attenuation coefficient at 6 MeV energy was S1 with 0.0432 cm²/g. The half-value layer of samples S2 and S3 exhibited a larger magnitude compared to samples S1. The tenth-value layer findings obtained with photons with 15 MeV energy were S0 < S1 < S2 < S3. In the experiments with photons with 6 MeV energy, the mean free path value of sample S1 was relatively lower than other samples. The experimental results were consistent with the data obtained from GAMOS and XCOM. Experiments and theoretical studies have shown that the Cerrobend alloy’s photon absorption properties are very similar to those of pure Cerrobend when it is doped with 5 wt% B₄C.

Keywords:
Boron; Cerrobend; GAMOS; Radiation Shielding; XCOM

1. INTRODUCTION

As ionizing radiation is more commonly used in medical procedures, different human organs and tissues will come into contact with X- and gamma-rays, particularly in radiotherapy. This exposure can lead to deterministic and stochastic radiation-induced consequences [¹]. To prevent deterministic and stochastic impacts from radiation, one can utilize techniques such as time, distance, and shielding [²]. Therefore, it is essential to minimize radiation exposure by utilizing shielding materials of appropriate thickness and the materials [³]. The basis of the design of shielding materials is based on photon matter interactions [⁴].

Materials with high density and high atomic numbers are preferred for radiation shielding. The development of innovative materials that can withstand the potentially severe circumstances associated with radiation exposure is a continuous area of research for researchers. The objective of these materials is to offer long-term radiation shielding, be cost-effective, environmentally benign, and non-toxic [⁵]. In this context, there are scientific researches in the literature on many different materials such as glass, concrete, polymers, alloys and ceramics in order to provide protection against X- and gamma rays [⁶,⁷,⁸].

B₄C reinforcement particles have been used in recent years to improve the mechanical and wear properties of composites by providing exceptionally high hardness, improved strength, chemical stability and higher thermal stability [⁹]. Moreover, boron compounds are exceptional materials for neutron shielding due to their ability to efficiently capture incoming neutrons, thereby preventing nuclear reactions and radiation leakage in nuclear applications [¹⁰]. Due to these properties, boron compounds are preferred for radiation shielding in many different materials. For instance, ISSA et al. investigated the role of increasing WO₃ in the network of boroditellurite glasses and reported that this increase strengthens boroditellurite glasses by increasing the density, hardness, and mechanical properties of the network, as well as increasing the radiation shielding property [¹¹]. Radiation exposure at different doses does not show any significant structural effects on borosilicate glasses [¹²]. Additionally, high-density alloys such as Cerrobend are effective in shielding against X-rays and gamma rays as a result of their high atomic number, which scatters and absorbs these forms of ionizing radiation, thereby reducing their penetration [¹³]. Comprehensive radiation shielding is achieved through this dual strategy. This combination is a valuable choice in a variety of industries where radiation shielding is a significant concern, as it provides comprehensive protection against a wide range of ionizing radiation.

Several parameters are used to assess the gamma and X-ray absorption characteristics of shielding materials, including the mean free path (MFP), half value layer (HVL), and tenth value layer (TVL). The absorption potential of a substance can be inferred from the total mass attenuation coefficient (MAC), which establishes the likelihood of interaction [¹⁴, ¹⁵]. Mean free path (MFP) is defined as the average distance between two consecutive interactions of photon with material [¹⁶]. Half value layer (HVL) and tenth value layer (TVL) are relevant parameters defined as the material thickness that reduces the incident radiation intensity by 50% and 10% respectively [¹⁷]. MAC and other radiation absorption parameters of different materials have been determined in various studies [¹⁸,¹⁹,²⁰,²¹,²²]. Some radiation shielding parameters, like MAC, HVL, TVL, and MFP, were examined in this study. They were found in four different types of Cerrobend alloys that had different amounts of B₄C. The total mass attenuation coefficient and MFP values of Cerrobend alloys frequently used in radiotherapy were calculated using 6 MeV and 15 MeV energies and dose values measured in the linear accelerator. Then, the experimental system was simulated using the code created with the GAMOS program for theoretical calculations. GAMOS is based on GEANT4 and is widely used for simulation studies in medical physics [²³, ²⁴]. The values of MAC, HVL, TVL, and MFP were determined using the data acquired from the GAMOS program. The HVL, TVL, and MFP values were computed for all alloys by extracting the MAC values from the XCOM (X-Ray Cross Section Database) database. A comparison was made between experimentally and theoretically derived radiation absorption values.

Two main mechanisms, so-called direct and indirect pathways, are involved in the degradation of DNA induced by ionizing radiations [²⁵]. In instances where ionizing radiation is unable to facilitate the repair of induced damage, cells may undergo either mutagenesis or apoptosis. Radiation shielding endeavors to mitigate the occurrence of mutation or apoptosis by impeding the exposure of healthy cells to radiation. Hence, this work aimed to investigate the impact of shielding fibroblast cells with a Cerrobend alloy having varying concentrations of B₄C on their post-irradiation survival rates. An endeavor was undertaken to establish a correlation between the ratios of B₄C and the rates of cell survival.

The aim of this research is to make experimental, theoretical and radiobiological comparative analysis of radiation shielding parameters of Cerrobend alloys doped with different amounts of B₄C. The current research is of significant importance in the context of designing a radiation shield that can be used in various radiotherapy applications, such as spatially fractionated GRID radiation therapy, to deliver the optimum dose to the tumor volume while ensuring that healthy tissue is exposed to the lowest possible dose of radiation [²⁶]. The findings of the present study can contribute to the investigation of a novel radiation shielding material, the selection of a suitable shielding material, and the determination of the optimal thickness of the shielding blocks. Cerrobend alloys are widely utilized in various domains, with a particular emphasis on their employment in radiation therapy. When cells are exposed to ionizing radiation and are unable to repair the resulting damage, they may undergo either mutation or apoptosis. Radiation shielding is designed to mitigate the occurrence of mutation or apoptosis by effectively limiting the exposure of healthy cells to radiation.

Consequently, this research aimed to investigate the impact of shielding fibroblast cells with varying concentrations of B₄C within a Cerrobend alloy on their post-irradiation survival rates. An endeavor was undertaken to establish a correlation between the ratios of B₄C and the rates of cell survival [²⁷,²⁸,²⁹]. They are often used as custom blocks to create a custom open size that can conform to the shape of the tumor to minimize doses outside the patient’s treatment area. The main advantages of Cerrobend alloys are (1) high density; (2) low melting temperature, but solid at room temperature; (3) easy molding and reuse; (4) ease of shaping; (5) low cost; and (6) consisting of elements with high atomic numbers (Cd, In, Sn, Sb, Bi, and Pb) [³]. In addition, B₄C is used in radiation shielding due to its mechanical, chemical and thermal properties [³⁰, ³¹]. B₄C alloys are suitable choices for radiation shielding applications that limit medical center worker exposure to gamma radiation [³²]. It has been documented in the literature that B₄C exhibits the capability to attenuate gamma rays, in addition to its neutron absorption properties [²¹, ³³,³⁴,³⁵,³⁶].

In our literature search, we did not come across a study investigating the radiation absorption properties of the cerrobend alloy, which is widely used in clinical practice, and a compound with high neutron absorption capacity and mechanical strength such as B₄C. In addition, although there are many experimental and theoretical studies on the radiation absorption properties of shielding materials, the examination of the biological effects of radiation under in vitro conditions is of great importance in medicine. In this context, we believe that including radiobiological data as well as radiation absorption parameters in this study will make an important contribution to the literature.

2. MATERIALS AND METHODS

2.1. Design of experimental groups

In this study, Cerrobend alloy (Radon Medical Equipment Import Export Sales and Trading Ltd. Co., Turkey) with a density of 9.47 g/cm³ and micron powder B₄C (Nanografi Nano Teknoloji A.Ş., Turkey) with 99.95% purity were used. To prepare Cerrobend-B₄C alloys with different boron carbide loadings (5, 10, and 15 wt% B₄C), B₄C powder was combined with the molten Cerrobend alloy at 98–100°C by homogeneous mixing (VELP Scientifica Srl., Italy) and poured into pre-prepared molds. After the blended mixture was cooled to room temperature, it was removed from the molds and became ready for dosimetric and radiobiological measurements. These processes were repeated for each shielding material. The elemental composition, density and sample code of the investigated alloys are listed in Table 1.

Table 1
The sample code, density and, composition of the alloy samples.

SAMPLE CODE	DENSITY (g/cm3)	COMPOSITION (% BY WEIGHT)
		CERROBEND	B4C
S0	9.47	100.00	–
S1	8.40	95.00	5.00
S2	7.41	90.00	10.00
S3	6.76	85.00	15.00

2.2. Radiation shielding tests

Radiation shielding tests are conducted on experimental measurements (LINAC system), theoretical calculations (XCOM [³⁷]) and Monte Carlo (MC) simulations (GAMOS [²⁴, ³⁸]).

Experimental measurements were made on the Varian Clinac IX® (Varian Medical System, USA) linear accelerator. During the measurement, 6 and 15 MeV photons were used. The experimental setup was created with solid water phantoms. Five slab phantoms, each 1 cm thick, were placed on the patient’s table to counteract the effect of backscatter radiation. After setup with solid phantoms, radiation doses were measured with the SN600c cylindrical ion chamber (Sun Nuclear Corporation SNC, USA). In the case of all Cerrobend-B₄C blocks, the distance from the source to the skin (SSD) was established at 100 cm, while the field size was adjusted to 10 × 10 cm² (Figure 1). For all irradiations, the Monitor Unit (MU) was established at a value of 1000 (1 MU = 1 cGy), while the dose rate was set at 600 MU/min.

Figure 1
Linear accelerator setup for the experimental method.

The theoretical computations in this work were conducted using the GAMOS v.6.2.0 software program. For GAMOS simulation, geometry and input files must be defined. In this study, bunker, gantry, parallel plate ion chamber and bolus were designed in the geometry file. A gantry geometry was created in the center of the linac bunker, which consists of air in the volume of 200 × 200 × 200 cm³. The gantry includes primary collimators, a beryllium window, scattering foil, an ion chamber, a jaw and an electron applicator with a 10 × 10 cm² area opening. In the simulation geometry, B₄C dopped Cerrobend alloys produced from different thicknesses were defined. A cylindrical ion chamber was designed for the measurement of the electron dose, and the SSD was defined as 100 cm in the geometry file (Figure 2).

Figure 2
Geometry of the GAMOS simulation used in the study.

The input file contained definitions for physics, generator, and the dose collection parameters. The simulation used the electromagnetic physics package. The simulations were conducted at energies of 6 MeV and 15 MeV. The scoring criteria involved tallying the quantity of dose that reached the detector through “dose deposit.” Variance reduction approaches were not utilized despite incorporating all physical processes in the score. A 10⁷ particles history was used to enhance the accuracy of the Monte Carlo simulations and minimize statistical error.

The considered radiation shielding parameters could be listed as LAC, MAC, HVL, TVL and MFP. The formulas of the considered parameters are given below [³⁹].

(1) $$\text{LAC =}\left(-\frac{ln\frac{I}{I_o}}{x}\right)$$

(2) $$\text{MAC =}\left(-\frac{ln\frac{I}{I_o}}{x}\right)/\text{ρ}$$

(3) $$\text{HVL =}\left(\frac{ln2}{\text{LAC}}\right)$$

(4) $$\text{TVL =}\left(\frac{ln10}{\text{LAC}}\right)$$

(5) $$\text{MFP =}\left(\frac{1}{LAC}\right)$$

where I₀, I, ×, and ρ represent the incident radiation density, transmitted radiation density, shielding material thickness, and shielding material density, respectively.

2.3. Radiobiological experiment

CCD-1135Sk An1 human skin fibroblast cell lines used for radiobiological measurements were purchased commercially. The ready-to-use medium was prepared by adding 10% Fetal Bovine Serum (FBS, Pan Biotech P30-3306) into DMEM/F12 (Pan Biotech P04-41250). The prepared medium was sterilized by passing through a 0.20 µm filter before application. Cells were incubated under sterile conditions in an incubator at 5% CO₂ and 37°C and proliferated.

The medium was emptied when the cells in 25 cm² flasks, which were routinely monitored daily under an inverted microscope, reached 80% confluency. 3 ml of Trypsin-EDTA solution was added to the flask and incubated at 37°C for 5–10 minutes. The suspended cells, losing their connection with the flask and each other, were transferred to 15 ml falcon tubes by adding 6 ml of medium. These falcons were centrifuged at 125 g for 6 minutes. Centrifuged cells were subcultured by dividing 1:6. The medium was changed every three days.

The 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test was used to investigate the effect of the shielding material on cell proliferation and growth. Cell growth and viability are analyzed by spectrophotometric measurement without the use of radioactive isotopes, which was made first by MOSMANN [⁴⁰]. Cells were seeded at 1 × 10⁶ cells/well in 96-well microplates. Microplates in the respective groups were irradiated with 6 MeV and 15 MeV photons at 1000 MU in a Varian Clinac IX® (Varian Medical System, USA) linear accelerator. A different microplate was prepared for each block, and these microplates were protected with blocks. During irradiation, the SSD value was 100 cm, and the dose rate was 600 MU/min. After irradiation, the cells were washed with PBS and left for 1 minute, after which the PBS was removed. Then, 100 μl of fresh culture medium and 10 μl of MTT stock solution were added to each well. It was wrapped in aluminum foil and kept in an incubator at 37°C for 4 hours. After the solution was removed after incubation, the culture medium containing MTT was removed by pipetting. 100 μl of DMSO was added to the cells and incubated at room temperature for 10 minutes. The absorbance value of 570 nm was measured in a microplate reader spectrophotometer. The entire experimental protocol was repeated three times.

3. RESULTS

3.1. LAC and MAC

LAC values exhibit significantly high values in low-energy regions of photon energy, where the photoelectric effect predominates. Within the central region of the gamma energies under investigation, the LAC values exhibited a negligible difference, owing to the Compton scattering section’s predominance [³²]. An increase in LAC is once more observed in the maximal values of incoming photons when double production is predominant. This trend has been the subject of numerous studies concerning the application of prepared materials for shielding [⁴¹,⁴²,⁴³]. The linear attenuation coefficients for the samples exposed to photons with an energy of 6 MeV and a field size of 10 × 10 cm² were 0.3902, 0.3629, 0.3060 and 0.2643 cm^–1 for S0, S1, S2, and S3, respectively. The linear attenuation coefficient values obtained from X-ray measurements with an energy of 15 MeV were 0.4934, 0.418, 0.3601 and 0.3137 cm^–1 for blocks of equal field size (Table 2).

Table 2
Linear attenuation coefficient of the alloy samples.

LAC (1/cm)	6 MeV				15 MeV
	S0	S1	S2	S3	S0	S1	S2	S3
LAC_Exp	0.3902	0.3629	0.3060	0.2643	0.4934	0.4183	0.3601	0.3137
LAC_GAMOS	0.4044	0.3620	0.3120	0.2589	0.5000	0.4259	0.3512	0.3096
LAC_XCOM	0.4000	0.3468	0.2987	0.2660	0.5085	0.4350	0.3695	0.3242

The mass attenuation coefficients for the samples exposed to photons with an energy of 6 MeV and a field size of 10 × 10 cm² changed between 0.0412 and 0.0391 cm²/g. The mass attenuation coefficient values obtained from X-ray measurements with an energy of 15 MeV were recorded as 0.0521, 0.0498, 0.0486 and 0.0464 cm²/g for blocks of equal field size. Figure 3 presents the experimentally acquired MAC findings from the GAMOS simulation and the XCOM database.

Figure 3
Mass attenuation coefficients of B₄C doped cerrobend alloys irradiated at varying photon energies (a) 6 and (b) 15 MeV were determined from experiments, GAMOS simulations, and the XCOM database.

The mass attenuation coefficients depend on the incident energy and the element concentration in the alloys. On the other hand, when low-energy X and gamma rays interact with matter, it causes a photoelectric effect that leads to the emission of photoelectrons. Also, the cross-section of Compton scattering is important for energies ranging from 100 keV to 10 MeV, and the pair production process becomes important for energies above 2 MeV, which plays an important role in the mass attenuation coefficient value [⁴⁴]. The MAC value decreases with increasing gamma-ray energy, which ranges from 13.8 keV to 15 MeV, due to the different densities and chemical compositions of the B₄C-doped Inconel 718 samples [⁴⁵]. The mass absorption coefficients of different alloys tend to decrease depending on the material usage, the B₄C ratio and the energy of the photons. Such changes in the mix design can result in a reduction in the density values of the alloy [⁴⁶]. When the gamma radiation shielding efficiency of polyethylene discs with different ratios of WC and B₄C doped compared to lead discs, the discs with 20% and 10% B₄C doped were 4.32% and 2.03% more efficient than the equivalent lead disc, respectively [⁴⁷]. Although the shielding ability decreases as the B₄C ratio increases, it is an important advantage that B₄C is a light and non-toxic material.

3.2. HVL and TVL

The experimental observations conducted using photons with an energy of 6 MeV revealed a range of HVL values between 1.7766 cm and 2.6224 cm. The HVL measurement for the S1 block was 1.6570 cm. However, it was noted that this value exhibited an increase to 2.2649 cm and 2.6224 cm for the S2 and S3 blocks, respectively, as the B₄C ratio was elevated. HVL values obtained using GAMOS simulation and the XCOM database were compatible with experimental results. The investigations conducted with 15 MeV photons yielded varying values for HVL, ranging from 1.4049 cm to 2.2098 cm. The HVL of samples S2 and S3 exhibited a greater magnitude in comparison to samples S0 and S1. The experimental results were consistent with the data obtained from GAMOS and XCOM. In experiments performed with 6 MeV energy photons, the HVL value of sample S1 was lower than S0, S2, and S3 (Table 3).

Table 3
Half-value Layer of the alloy samples.

HVL (cm)	6 MeV				15 MeV
	S0	S1	S2	S3	S0	S1	S2	S3
HVL_Exp	1.7766	1.9101	2.2649	2.6224	1.4049	1.6570	1.9247	2.2098
HVL_GAMOS	1.7141	1.9146	2.2219	2.6772	1.3863	1.6276	1.9735	2.2388
HVL_XCOM	1.7328	1.9990	2.3206	2.6058	1.3630	1.5933	1.8757	2.1380

TVL findings obtained with 15 MeV energy photons were S0 < S1 < S2 < S3. Similarly, GAMOS and XCOM results were in agreement with experimental findings (Figure 4).

Figure 4
Tenth value layer of blocks at 6 MeV and 15 MeV photon energies.

The study found that the HVL and TVL for photons with an energy of 6 MeV were greater than those for photons with an energy of 15 MeV. The HVL and TVL values stabilize and remain relatively steady after reaching 1 GeV. The observed phenomenon, such as the alteration in the MAC value and the variations in HVL and TVL, can be attributed to the prevalence of distinct photon interaction mechanisms across various energy ranges [³].

In the literature, the gamma radiation absorption ability of B₄C-doped AISI 316 stainless steel decreases with increasing B₄C content [⁴⁸]. The HVL value increased with the increase of B₄C content in Inconel 718 superalloy matrix composites with B₄C doped at different rates. The HVL values for these composites ranged from 0.018 cm to 0.9 cm in the low-energy region and between 0.9 cm and 3.6 cm in the high-energy region [⁴⁵]. In addition, in a study aiming to increase the radiation shielding ability of concrete, the radiation absorption properties of concrete with different ratios of WC and B₄C were investigated theoretically and experimentally. The results of the study showed that the modified compositions have more advantages compared to pristine concrete. They also revealed that the shielding parameters were highly dependent on the atomic composition of the prepared concrete and the density of the additives. So, it has been shown that adding the right amount of WC and B₄C to concrete can be a different option that can be used for radiation protection in different ways [⁴⁹].

3.3. The mean free path (MFP)

MFP values were calculated for each block with the dosimetric measurement results made with photons at 6 MeV and 15 MeV energies. In experiments conducted with photons with 6 MeV energy, it was observed that as the B₄C ratio by weight increased, the MFP value also increased. On the other hand, in experiments conducted with photons with 15 MeV energy, it was observed that the MFP value for all samples was lower than that of 6 MeV. The R² values of the experimental and theoretical MFP results were 0.96 and 0.99 for 6 and 15 MeV, respectively (Figure 5).

Figure 5
Experimental and theoretical mean free path values and determination. Coefficients (R²) of all blocks at (a) 6 MeV photon and (b) 15 MeV photon energies.

MFP values obtained as a result of dosimetric measurements made with 15 MeV photons are similar to those obtained with 6 MeV photons. It has been shown that the MFP values belong to concretes with a density of 1.81 and 2.27 g/cm³, respectively [⁵⁰]. It can be easily deduced that the MFP parameter depends on the concrete density, and the shielding performance is proportional to the density of the material. In the study conducted by YORULMAZ et al. [⁵¹], it is observed that the MFP values of the samples with lower densities are higher due to the changes in the chemical composition of Gd₂O₃ doped borate glasses. In a study investigating the radiation absorption properties of SiC and B₄C-embedded EVA copolymers, the MFP values measured for polymer composites were lower than those of pure EVA polymer. Polymer composites with different compositions, such as SiC (30%), Si (15%) + B₄C (15%), or SiC (15%) + B₄C (15%), were found to block 90–91% of photons at around 80 keV [⁵²].

3.4. Radiobiological results

The fibroblast cells in the control group were not subjected to radiation exposure. Therefore, the group with the highest survival rate was the control group. The study determined that the survival rate of fibroblast cells following exposure to 6 MeV energy photons was 0.232 for S0. The observed viability of irradiated cells following closure with the S1 block exhibited a greater rate of survival in comparison to closures performed with the S2 and S3 blocks. The percentage of fibroblast cells that remained viable following exposure to 15 MeV energy photons was 0.1901 for S3. The study observed that the survival rate of fibroblast cells, when protected by S0, was 0.4637, which was comparatively higher than the survival rates observed for S1 and S2 (Figure 6).

Figure 6
Cell viability in fibroblasts exposed to (a) 6 MeV and (b) 15 MeV photons.

Cell survival depends on many variables, such as radiation energy, dose amount, and dose rate [⁵³]. Survival rates for cells exposed to radiation are inversely proportional to increasing dose amount and energy. Radiation exposure can cause genotoxic damage as well as cytotoxic effects on cells. Chromosomal damage occurs with increasing X-ray energy [⁵⁴].

3.5. Limitations

This study had some limitations. The cylindrical ion chamber’s effect parameters are one of them. Temperature, pressure, humidity, polarity, and recombination comprise these effect parameters. In order to accurately assess the measured signal, the effect parameters must be corrected if the ion chamber is operated under conditions that differ from the reference conditions. In order to reduce measurement errors, the contributions of these parameters were corrected prior to each measurement during this investigation. After these corrections, it is known that the cylindrical ion chamber makes measurements with errors less than 0.4% [⁵⁵]. Another limitation is that while GAMOS is fairly accurate in predicting radiation interactions with matter, it does not take into account chemical changes that may occur in matter as a result of radiation exposure. This could potentially result in a little variance between the simulation and the experimental results. Although there were several limitations, the variation in radiation shielding characteristics observed in this study was less than 2%.

4. CONCLUSIONS

It was the purpose of this research to simulate and analyze the radiation absorption properties of Cerrobend alloys containing varying quantities of B₄C. The data obtained through simulation and experimentation on the B₄C-doped cerrobend alloys under investigation yielded the following conclusions:

• The minimum LAC value recorded using 6 MeV photons was 0.2643 cm^–1 for sample S3. Similarly, the lowest value obtained with 15 MeV photons was 0.3137 cm^–1, also for sample S3.

• The MAC values for S0, S1, S2, and S3 blocks were 0.0521, 0.0498, 0.0486, and 0.0464 cm²/g, respectively, as obtained from 15 MeV energy X-ray measurements.

• As the gamma energy increases, HVL and TVL both increase. Similar outcomes were achieved with both the experiment, XCOM and GAMOS data.

• It was noted that the MFP values increased in proportion to the quantity of B₄C. The MFP value varied between 2.563 cm and 3.783 cm in the measurements conducted with 6 MeV photons, and between 2.027 cm and 3.188 cm in the measurements conducted with 15 MeV photons.

• After exposure to both 6 MeV and 15 MeV energy photons, the survival rate of fibroblast cells protected with 5 wt% B₄C-doped Cerrobend alloy was higher than that of cells protected with 10 wt% and 15 wt% B₄C-doped Cerrobend alloys.

• The study findings demonstrated that the radiation absorption characteristics exhibited variations in accordance with changes in both the density and chemical composition of the samples.

• The material’s ability to absorb photons decreased as the quantity of B₄C increased.

• Experimental and theoretical studies have shown that the photon absorption properties of Cerrobend alloy with 5 wt% B₄C addition exhibit close performance to pure Cerrobend.

• The findings show that the Monte Carlo approach is applicable in the presence of experimental limitations.

5. ACKNOWLEDGMENTS

This research has been supported by Kutahya Dumlupınar University Scientific Research Projects Coordination Office under grant number #2021-29. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Publication Dates

• Publication in this collection
  11 Oct 2024
• Date of issue
  2024

History

• Received
  20 June 2024
• Accepted
  15 Aug 2024