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In the current study, 10PbO-xSrO-(90-x)B2O3 (x is between 20 and 45 mol% with a step of 5 mol%) glasses with SrO inserted in various proportions were surveyed in terms of nuclear shielding qualities. Gamma- ray shielding features of the glasses encoded BPS1-BPS6 were investigated in the energy range of 0.015–15 MeV. The mass attenuation coefficients (MAC) of BPS glasses were composed via GEANT4 simulation codes and the accuracy of the outcomes was checked by WinXCOM software. The MAC values of BPS1 and BPS6 glasses were obtained between 14.934–0.024 g/cm2 and 19.047–0.029 g/cm2 in the energy range of 0.015–15 MeV. Further, other essential parameters, MFP, Zeff, Zeq, EABF, and EBF were derived from the MAC values for the same energies. It was noted that the MFP values of the BPS6 glass are higher than some commercial glasses and ordinary concrete at chosen energy intervals. According to the results achieved, EBF, EABF, and MFP values decline as the percentage of SrO in the BPS glasses increases. The highest Zeff was achieved by BPS6 (with 45% SrO), while the lowest Zeff was obtained by BPS1 (with 20% SrO). Finally, fast neutron removal cross-sections (ΣR), Mass Stopping Power (MSP), and Projected Range (PR) values were computed to investigate the fast neutron, proton and alpha shielding properties of SrO added BPS glasses. It is seen that the ΣR values of BPS glasses vary in the range of 0.126 cm−1–0.117 cm−1. The addition of SrO in the glass leads to reduce the ranges of charged and uncharged particles. According to the outcomes achieved, BPS6 glass with 45% SrO additives can be regarded as an effective radiation shield used in many technological disciplines.

Five new strontium barium borate (BNBD) glasses doped with dysprosium ion and different concentrations of niobium pentoxide were synthesized using the standard melt-quenching method. The physical, structural, optical and gamma radiation shielding properties of these glasses were investigated. Density, average molecular weight, refractive index, molar volume, optical dielectric constant, boron-boron separation, metallization criterion, oxygen packing density, Poisson ratio, optical basicity, optical electronegativity, and two-photon absorption coefficients of the synthesized glasses were determined. By the addition of Nb2O5 content, boron-boron distance and oxygen packing density values increased, while molar volume of oxygen decreased due to the formation of bridging oxygen. The two-photon absorption could be constrained by replacing BaCO3 by niobium pentoxide content which further influences the bandgap. The ionic nature of the titled glasses is discussed using the bonding parameter, optical basicity, ionic and covalent characteristic parameter values. Moreover, the shielding ability of dysprosium ions doped niobium borate glasses against photons, fast neutrons and electrons has been extensively evaluated. For this purpose, the mass attenuation coefficient (µ/ρ, cm2/g) of the glasses and several photon protection parameters, derived from µ/ρ were obtained for 0.015–15 meV. The maximum µ/ρ values were achieved for BNBD0 glass, varying between 0.033 and 35.430 cm2/g. The lowest buildup factor values were found for BNBD0 glass. Furthermore, effective removal cross section values for fast neutrons increased steadily between 0.125 and 0.130 cm−1 due to the increase in the density of the glasses with the enhancing of Nb2O5 concentration. It was noticed that the range of high energy electrons was shorter on the BNBD0 glass. It was concluded that BNBD0 glass with high BaCO3 concentration can be considered as an alternative material in nuclear radiation shielding applications.

This paper aims to study gamma and beta attenuation characteristics of newly developed 60Se- 20Ge (20 – x)-Sb-xAg (where x varies from 0 to 20 mol% with step of 5) Chalcogenide glasses. Geant4 toolkit was utilized mainly to explore gamma-ray attenuation properties by determining linear attenuation coefficient (μ) for the chosen samples. The obtained results were compared with the theoretical approach applying via XCOM program. Then, we utilized the μ values to compute effective atomic number (Zeff) and half value layer (HVL). For the sample coded as SGSA1, the μ values are 0.191 and 0.180 cm−1 between 3 and 4 MeV, while they are 0.175 and 0.197 cm−1 between 6 and 15 MeV respectively. The HVL varied between 0.001492 and 0.001317 cm at 0.015 MeV and 0.021955–0.021439 cm at 0.05 MeV. ESTAR program was employed to investigate beta attenuation properties by estimation CSDA range and TSP factors of the incident electron. It was noted that there is a significant influence of silver on the radiation shielding characteristics of the tested materials. Moreover, we compared the studied glasses with commercial glasses and traditional concrete in term of MFP. The results showed the possibility of use the studied materials for the radiation shielding applications.

Nonlinear and linear optical traits of vanadio–tellurite glasses in the form 50TeO2-(50-x)V2O5-xK2O (where x = 0–20 mol% (abbreviated as TVK glasses) were investigated. Besides, gamma ray shielding parameters were assessed utilizing the FLUKA simulation code. Results revealed that the molar refraction (Rmolar) varied from 31.122 to 26.400 (cm3/mol), while molar polarizability (αmolar) varied from 12.350 × 10−24 to 10.476 × 10−24 cm3. The static dielectric constant (estatic) was within 10.298–6.789. The optical electronegativity (χ*) varied from 0.319 to 0.626 for TVK glasses. The nonlinear refractive index (nOptical) diminished from 5.996 × 10−10 to 1.109 × 10−10 (esu), while the nonlinear optical susceptibility (χ3) diminished from 5.107 × 10−11 to 0.767 × 10−11 (esu) with the V2O5/K2O substitution in the glasses. Gamma ray attenuation coefficients such as μ and μ/ρ were calculated for six different photon energies in the range of 0.284–1.275 MeV. Both μ and μ/ρ were used to evaluate the transmission factors (HVL and MFP) and the effective atomic number (Zeff). The Zeff parameter was useful to give a full understanding of the gamma ray shielding performance of the TVK glasses under V2O5/K2O substitution. Finally, the parameters of gamma ray shielding were compared with ordinary and commercial shielding materials.

This paper aims to study the photon and electron attenuation parameters of phosphate and borate bioactive glasses such as 45P2O5–55Li2O, 50P2O5–50Li2O, 55B2O3–45Li2O, and 2.6P2O5-46.1SiO2-24.4Li2O-26.9CaO. Geant4 toolkit was carried out to simulate the interactions of photon and electron with the glasses at medical diagnostic energies between 30 keV and 80 keV. The correct implementation of the simulation values was confirmed by using the corresponding values calculated from the Phy-X program. Photon attenuation studies were achieved by evaluating linear and mass attenuation coefficients (μ, μ/ρ), effective atomic number for total photon interaction (Zeff), and half value layer (HVL). Electron attenuation studies were investigated by determining the electron stopping power (Ψ) for each glass sample. Moreover, the mean energy deposited (dE/dx) in the glass sample was estimated for photon and electron interactions. The results showed that the chemical composition of the glass has a strong influence on the photon interactions and weak influence on the electron interactions. Furthermore, the maximum dE/dx values were observed at 30 keV and 80 keV for the photon interactions and electron interactions, respectively.

Ag2O–MoO3–V2O5–TeO2 (AMVT) glasses were reported by means of their optical properties such as polarizability, optical transmission, and optical basicity. Moreover, the photon attenuation properties were explored by using FLUKA simulation code for energies up to 1.275 meV. From the optical study, it was noted that the molar polarizability (αMol.) decreased from 11.8630 × 10–24 to 9.4846 × 10–24 cm3, while the optical transmission increased from 0.5498 to 0.5976 as the Ag2O concentration increased from 0 to 25 mol%. From the photon attenuation study, the maximum values of µ/ρ (MAC, mass attenuation coefficient) were observed at 0.284 meV. Such those values were 0.1501, 0.1525, 0.1549, 0.1572, 0.1593 and 0.1616 cm2/g for AMVT1, AMVT2, AMVT3, AMVT4, AMVT5 and AMVT6, respectively. From the view of practical application, it is found that the HVL values of the AMVT glasses are evidently lower than those of ordinary concrete and RS-253-G18 commercial glass.

The radiation shielding properties of xPbO-(100-x)TeO2, x = 10, 20, and 30 mol% binary glasses and y[ZnO]-(100-y)[70(TeO2)-30(PbO)] y = 15, 20, and 25 mol% ternary glasses were investigated using Geant4 simulations and the newly developed Phy-X/PSD program. The glasses’ gamma shielding abilities were assessed using their mass attenuation coefficient (μ/ρ), mean free path (MFP), effective atomic number (Zeff), and half value layer (HVL) values. The neutron shielding ability was evaluated by determining the removal cross-section (RCS) values, which were 0.097, 0.101, and 0.103 cm-1 for binary PbO-TeO2 (PT) glasses and 0.118, 0.116, and 0.114 cm-1 for ternary ZnO-PbO-TeO2 (PTZ) glasses. The gamma and neutron shielding features of the glasses were compared with those of various ordinary concretes and Pb-free, Pb-based, and commercial glasses. The addition of PbO changed the gamma and neutron properties of the PT glasses, while the addition of ZnO demonstrated a different trend in the gamma properties of the PTZ glass system.

In this paper, the radiation shielding properties of chalcogenide glass-ceramics with the chemical composition of xCsCl-(100−x)(0.5GeS2-0.5Sb2S3), where 0 ≤ x ≤ 40 mol%, were investigated by using Geant4 simulations, G-P method, and Phy-X/PSD program. Mass attenuation coefficient (μ/ρ), half value layer (HVL), removal cross section (RCS), exposure buildup factor (EBF), mean free path (MFP), and effective atomic number (Zeff) were evaluated to elucidate the radiation shielding competence of the present chalcogenide glass-ceramics. A good agreement was noted between the μ/ρ values of Geant4 simulations and theoretical calculations. At 15 MeV, we found that the HVL values raised from 5.276 cm to 5.728 cm as the concentration of CsCl increased from 0 to 40 mol%. Maximum Zeq values occurred at 1 MeV and were 42.20, 42.98, 43.76, 44.57, and 45.40 for GSC-A, GSC-B, GSC-C, GSC-D, and GSC-E, respectively. The results revealed that the chalcogenide glass-ceramics have radiation shielding properties superior to those of commercial glasses, and traditional concrete.

This paper focuses on the evaluation of the radiation attenuation properties of 15CaF2-10CaO-5B2O3-(65-x)P2O5-xNiO-5BaO (where 0 ≤ x ≤ 1.0 mol%) bioactive glasses. The radiation attenuation features of these glasses were investigated by determining different factors including mass attenuation coefficient (μ/ρ), exposure and absorption buildup factors (EBF and EABF), neutron removal cross section (NRCS), and effective atomic number (Zeff) for photon, proton, and carbon ion interactions. Geant4 toolkit and Phy-X program were employed for simulations and calculations procedures. The results revealed that NiO content in the studied bioactive glasses has a significant effect on photon interaction and an insignificant effect on the charged particle interactions. The Zeff values of the studied glasses were observed in the range of 18–20 for photon interaction, 10.7–10.9 for proton interaction, and 10.0–10.7 for carbon ion interaction. The NRCS values were 0.087, 0.088, 0.089, 0.090, and 0.091 cm-1 for x = 0, 0.4, 0.6, 0.8 and 1.0 mol%, respectively. The studied bioactive glasses showed a good ability to attenuate gamma radiation at energies of medical applications.

This paper focuses on the effect of Bi2O3 content (up to 80 mol%) on mechanical features and radiation shielding characteristics of boro-tellurite glasses within TeO2–B2O3–Bi2O3 system. The basic mechanical parameters such as oxygen molar volume, packing density, hardness, and elastic moduli were studied based on Makishima–Mackenzie's theory. The shielding studies of the TeO2–B2O3–Bi2O3 glasses included gamma, electron and neutron radiations. The newly developed Phy-X/PSD program and Geant4 simulation were used to calculate the shielding parameters such as mass attenuation coefficient (μ/ρ), tenth value layer (TVL), mean free path (MFP), stopping power (ψe)), removal cross section (RCS), CSDA range, effective atomic number (Zeff), and half value layer (HVL). The concentration of Bi2O3 content had a significant effect on the gamma shielding competence of the investigated glasses. Form the results of gamma shielding studies, the highest μ/ρ (99.845 cm2/g) occurred at 0.015 MeV for TBB80 and the lowest μ/ρ (0.039 m2/g) occurred at 4 MeV for TBB40. The maximum values of Zeff for gamma interaction occurred at 0.02 MeV and they were 77.26, 78.81, 79.94, 80.80, and 81.48 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The gamma shielding features of the investigated glasses were compared with those of various ordinary concretes, and Pb-free, Pb-based, and commercial glasses. The Bi2O3 content had also a considerable influence on the electron shielding competence of the tested glasses. The maximum values of Zeff for electron interaction occurred at 14 MeV and they were 44.58, 47.72, 50.41, 52.75, and 53.73 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The results revealed that the bismuth boro-tellurite glasses could be useful for the shielding against gamma, electron, and neutron radiations, wherein the Bi2O3 content can be balanced according to the type and energy of radiation.

This work aimed to investigate the mechanical features and radiation shielding properties of (100–2x)TeO2+xAg2O + xWO3 (where x = 7.5, 15, 22.5, and 30 mol%) glass system. Based on Makishima–Mackenzie's theory, the basic mechanical features such as packing density, Poisson's ratio, elastic moduli, hardness, and fractal bond connectivity were studied. The shielding investigations included the radiations of gamma, electron, neutron, and heavy charged particles. Geant4 toolkit and newly developed Phy-X program were employed to evaluate mass attenuation coefficient (μ/ρ), transmission factors (HVL and MFP), exposure buildup factor (EBF) and effective atomic number (Zeff) of gamma and charged particles for the studied glasses. Neutron shielding investigation was examined by determining neutron removal cross section (NRCS) of the glasses involved. The results showed that Ag2O and WO3 contents had an insignificant effect on the mechanical properties of the investigated glass system. In contrast, the Ag2O and WO3 contents had a significant effect on the shielding capacity of the glasses against gamma radiation and charged particles. The Zeff values were in the range of 24–60 for gamma, 24–31 for electron, 18–24 for proton, 15–23 for alpha, and 13–19 for carbon ion. The shielding properties of these glasses were compared with those of commonly used shields. The investigated glass system can be used in shielding applications, wherein Ag2O and WO3 contents can be balanced with the TeO2 content according to the type and energy of the radiation.

A new bioactive glass system with the structure of P2O5-Na2O-CaO-K2O-MgO (PNCKM) was prepared and assessed for use in radiation shielding applications. X-ray diffraction (XRD) and scanning electron microscope measurements were achieved for the prepared glasses. Gamma radiation shielding parameters such as mass attenuation coefficient (μ/ρ), effective atomic number (Zeff), and mean free path (MFP) were investigated by using Geant4 toolkit at nuclear medicine energies namely; 0.083 MeV emitted from 201Tl, 0.140 MeV emitted from 99Tc, and 0.284, 0.365, 0.637, and 0.723 MeV emitted from 131I. The obtained results are confirmed via the newly developed Phy-X/PSD program. At 0.365 MeV, the Zeff values were 10.31, 10.53, 10.76, 10.99, and 11.24 for PNCKM1, PNCKM2, PNCKM3, PNCKM4, and PNCKM5, respectively. The gamma shielding features of the PNCKM glasses were compared with those of commercial and conventional shielding materials in terms of half value layer (HVL). Moreover, neutron shielding features such as removal cross section (ΣR) were calculated for the prepared glasses and compared with those of standard bioactive glasses. The prepared glasses can be useful to design superior radiation shielding materials as well as to optimize the fabrication of low cost and environmentally friendly shields.

World-wide, on-going intensive research is being seen in adaptation of carbon nanotubes (CNTs) for a wide variety of applications, particular interest herein being in the thermoluminescent (TL) properties of CNTs and their sensitivity towards energetic radiations. Using beta radiation delivering dose levels of a few Gy it has been observed in previous study that strain and impurity defects in CNTs give rise to significant TL yields, providing an initial measure of the extent to which electron trapping centres exist in various qualities of CNT, from super-pure to raw. This in turn points to the possibility that there may be considerable advantage in using such media for radiation dosimetry applications, including for in vivo dosimetry. CNTs also have an effective atomic number similar to that of adipose tissue, making them suitable for soft tissue dosimetry. In present investigations various single-wall carbon nanotubes (SWCNT) samples in the form of buckypaper have been irradiated to doses in the range 35–1.3 Gy, use being made of a 90 Sr beta source, the response of the CNTs buckypaper with dose showing a trend towards linearity. It is shown for present production methodology for buckypaper samples that the raw SWCNT buckypaper offer the greatest sensitivity, detecting doses down to some few tens of mGy.

In this study, new glasses with a nominal composition of 40Bi2O3–10Na2O-(50-x)B2O3-xCu2O (where 0 > x > 6 wt%), were fabricated by using the standard melt-quench technique. A Bruker XRD diffractometer model AXS D8 Advance was carried out to investigate the amorphous state for the fabricated glasses. The optical features such as bandgap (Eg), molar refraction (Rm), Urbach energy (Eu), metallization principle (M), molar polarizability (αm), optical transmission (T), and reflection loss (RL), were investigated by using the ultraviolet spectrum. The radiation shielding capability of the fabricated glasses was estimated by using FLUKA code and the Phy-X software for varied photon energies. The mass attenuation coefficient (µ/ρ) and other related factors such as half value layer (HVL) and effective atomic number (Zeff) were calculated. The results revealed that there is a notable effect of Cu2O on the optical properties of the glasses involved. As the Cu2O content changed from 0 to 6 mol%, the density of the fabricated glasses increased from 5.128 to 6.214 g/cm3 and the optical transmission decreased from 0.697 to 0.655. On the other hand, the Cu2O content enhanced the nuclear-shielding against gamma-rays. The shielding capability of the fabricated glasses was compared with many samples in terms of MFP. The fabricated glasses showed superior features to apply for optical and gamma shielding applications.

This paper focuses on the role of antimony oxide (up to 15 wt%) in the physical, structural, optical, and radiation attenuating characteristics of boro-bismuth glasses within B2O3-20Bi2O3- 20Na2O2- Sb2O3 system. This glass system was prepared by melting at 1250°C and quenching into water. The physical properties were studied by measuring the density, molar volume, and x-ray diffraction for the prepared glass system. The structural features were investigated by determining packing density, passion ratio, oxygen packing density, and oxygen molar volume. The optical attributes were explored by evaluating bandgap, Urbach energy, refractive index, and other related parameters such as dielectric constant, reflection loss, molar polarizability, molar refractivity, optical dielectric constant, optical electronegativity, electron polarizability, optical basicity, metallization, and cut-off wavelength. On the other hand, the shielding properties of the prepared glasses were studied against different types of radiation such as gamma, electron, proton, and neutron beams. The radiation studies were carried out by utilizing Geant4 simulations and the newly developed Phy-X/PSD program. The radiation-shielding characteristics of the present samples were examined in terms of mass attenuation coefficient, stopping power, half value layer, removal cross section, mean free path, and effective atomic number of gamma, electron, and proton beams. The results showed that antimony oxide content had an important influence on the shielding ability against all of the types of radiations. Additionally, the obtained results were compared with those of standard radiation shields. It can be concluded that the present glasses have a promising future to be used as radiation shielding material, wherein the antimony oxide concentration can be balanced according to the desired application.

Two thermoluminescent dosimeters (SiO-GeO doped fibres and glass beads (GB)) were used to measure small photon field doses and compared against GAFCHROMIC film, a small ionisation chamber (RK-018) and a p-type silicon diode (SCANDITRONIX, F1356), as well as Monte Carlo simulations with FLUKA and BEAMnrc/DOSXYZnrc. Ge-doped SiO fibres have been shown by this group to offer a viable system for use as dosimeters. The fibres and GB offer good spatial resolution (~120μm and 2mm respectively), large dynamic dose range (with linearity from tens of mGy up to well in excess of many tens of Gy), are non-hygroscopic and are of low cost. Measurements of beam profiles for field sizes of 10mm×10mm, 20mm×20mm, 30mm×30mm, 40mm×40mm, and 100mm×100mm were carried out. Through the use of a customised solid water phantom, doped optical fibres and GBs were placed at defined positions along the x-and y-axes to allow accurate beam profile measurement. The maximum difference between FWHM measurements was 1.8mm. For penumbra measurements (measured between 80% and 20% isodoses), the maximum difference was

The Ge dopant in commercially available silica optical fibres gives rise to appreciable thermoluminscence (TL), weight-for-weight offering sensitivity to MV X-rays several times that of the LiF dosimeter TLD100. The response of these fibres to UV radiation, X-rays, electrons, protons, neutrons and alpha particles, with doses from a fraction of 1Gy up to 10kGy, have stimulated further investigation of the magnitude of the TL signal for intrinsic and doped SiO fibres. We represent a consortium effort between Malaysian partners and the University of Surrey, aimed at production of silica fibres with specific TL dosimetry applications, utilizing modified chemical vapour deposition (MCVD) doped silica-glass production and fibre-pulling facilities. The work is informed by defect and dopant concentration and various production dependences including pulling parameters such as temperature, speed and tension; the fibres also provide for spatial resolutions down to

We describe investigation of a novel undoped flat fibre fabricated for medical radiation dosimetry. Using high energy X-ray beams generated at a potential of 6MV, comparison has been made of the TL yield of silica flat fibres, TLD-100 chips and Ge-doped silica fibres. The flat fibres provide competitive TL yield to that of TLD-100 chips, being some 100 times that of the Ge-doped fibres. Pt-coated flat fibres have then been used to increase photoelectron production and hence local dose deposition, obtaining significant increase in dose sensitivity over that of undoped flat fibres. Using 250kVp X-ray beams, the TL yield reveals a progressive linear increase in dose for Pt thicknesses from 20nm up to 80nm. The dose enhancement factor (DEF) of (0.0150±0.0003)nm Pt is comparable to that obtained using gold, agreeing at the 1% level with the value expected on the basis of photoelectron generation. Finally, X-ray photoelectron spectroscopy (XPS) has been employed to characterize the surface oxidation state of the fibre medium. The charge state of Si2p was found to lie on 103.86eV of binding energy and the atomic percentage obtained from the XPS analysis is 22.41%. © 2014 Elsevier Ltd.

An investigation has been made of glass beads and optical fibres as novel dosimeters for small-field photon radiation therapy dosimetry. Commercially available glass beads of largest dimension 1.5 mm and GeO2-doped SiO2 optical fibres of 5 mm length and 120 µm diameter were characterized as thermoluminescence dosimeters. Results were compared against Monte-Carlo simulations with BEAMnrc/DOSXYZnrc, EBT3 Gafchromic film, and a high-resolution 2D-array of liquid-filled ionization chambers. Measurements included relative output factors and dose profiles for square-field sizes of 1, 2, 3, 4, and 10 cm. A customized Solid-Water® phantom was employed, and the beads and fibres were placed at defined positions along the longitudinal axis to allow accurate beam profile measurement. Output factors and the beam profile parameters were compared against those calculated by BEAMnrc/DOSXYZnrc. The output factors and field width measurements were found to be in agreement with reference measurements to within better than 3.5% for all field sizes down to 2 cm2 for both dosimetric systems, with the beads showing a discrepancy of no more than 2.8% for all field sizes. The results confirm the potential of the beads and fibres as thermoluminescent dosimeters for use in small photon radiation field sizes.

Recent developments in advanced radiotherapy techniques using small field photon beams, require small detectors to determine the delivered dose in steep dose gradient fields. Commercially available glass jewellery beads exhibit thermoluminescent properties and have the potential to be used as dosimeters in radiotherapy due to their small size (

Review is made of dosimetric studies of Ge-doped SiO telecommunication fibre as a 1-D thermoluminescence (TL) system for therapeutic applications. To-date, the response of these fibres has been investigated for UV sources, superficial X-ray beam therapy facilities, a synchrotron microbeam facility, electron linear accelerators, protons, neutrons and alpha particles, covering the energy range from a few eV to several MeV. Dosimetric characteristics include, reproducibility, fading, dose response, reciprocity between TL yield and dose-rate and energy dependence. The fibres produce a flat response to fixed photon and electron doses to within better than 3% of the mean TL distribution. Irradiated Ge-doped SiO optical fibres show limited signal fading, with an average loss of TL signal of ~0.4% per day. In terms of dose response, Ge-doped SiO optical fibres have been shown to provide linearity to x and electron doses, from a fraction of 1Gy up to 2kGy. The dosimeters have also been used in measuring photoelectron generation from iodinated contrast media; TL yields being some 60% greater in the presence of iodine than in its absence. The review is accompanied by previously unpublished data. © 2012 Elsevier Ltd.

We investigate the ability of high spatial resolution (∼120μm) Ge-doped SiO(2) TL dosimeters to measure photoelectron dose enhancement resulting from the use of a moderate to high-Z target (an iodinated contrast media) irradiated by 90kVp X-rays. We imagine its application in a novel radiation synovectomy technique, modelled by a phantom containing a reservoir of I(2) molecules at the interface of which the doped silica dosimeters are located. Measurements outside of the iodine photoelectron range are provided for using a stepped-design that allows insertion of the fibres within the phantom. Monte Carlo simulation (MCNPX) is used for verification. At the phantom medium I(2)-interface additional photoelectron generation is observed, ∼60% above that in the absence of the I(2), simulations providing agreement to within 3%. Percentage depth doses measured away from the iodine contrast medium reservoir are bounded by published PDDs at 80kVp and 100kVp.

Present interest concerns development of a system to measure photoelectron-enhanced dose close to a tissue interface using analogue gold-coated doped silica-fibre thermoluminescence detectors and an X-ray set operating at 250. kVp. Study is made of the dose enhancement factor for various thicknesses of gold; measurements at a total gold thickness of 160. nm (accounting for incident and exiting photons) produces a mean measured dose enhancement factor of 1.33±0.01 To verify results, simulations of the experimental setup have been performed. © 2013 Elsevier Ltd.