Duncan J. Butler , Micah Barnes , Malcolm R. McEwen , Michael L.F. Lerch , Suzie L. Sheehy , Yaw-Ren E. Tan , Ivan M. Williams , Jacinta S.L. Yap
{"title":"Dosimetry for FLASH and other non-standard radiotherapy sources","authors":"Duncan J. Butler , Micah Barnes , Malcolm R. McEwen , Michael L.F. Lerch , Suzie L. Sheehy , Yaw-Ren E. Tan , Ivan M. Williams , Jacinta S.L. Yap","doi":"10.1016/j.radmeas.2024.107330","DOIUrl":"10.1016/j.radmeas.2024.107330","url":null,"abstract":"<div><div>We review current dosimetry practices for non-standard radiotherapy sources. We classify radiotherapy sources as established, variations of established, or novel. Our review concentrates on novel sources including ultra-high dose-rate (FLASH) sources and some that have yet to be used for clinical radiotherapy. Factors which differentiate non-standard sources include dose-rate, temporal pulse structure, spatial fractionation, focussing, the presence of magnetic fields, and energy range. For the most part we exclude techniques which use materials inside the tumor to modify the dose. Dosimetry techniques include ionization chambers, film, alanine, calorimetry, and solid-state detectors. We review dosimetry only, neglecting other issues such as beam monitoring, patient delivery systems and treatment planning.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"180 ","pages":"Article 107330"},"PeriodicalIF":1.6,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermal stability of the bleachable and unbleachable components of the ESR signals in sedimentary quartz","authors":"Naoya Obata , Shin Toyoda","doi":"10.1016/j.radmeas.2024.107327","DOIUrl":"10.1016/j.radmeas.2024.107327","url":null,"abstract":"<div><div>The thermal stability of the bleachable and unbleachable components of the electron spin resonance signals in quartz grains from modern fluvial sediments were investigated. It was found that the unbleachable Al center is thermally more stable than the bleachable component, hence the unbleachable component can be extracted by heating. Protocols for equivalent dose evaluation with preheating are proposed, in which the procedure of bleaching is replaced by “partial annealing” (heating at 280 °C for 15 min) for the Al center and by “annealing” (heating at 400 °C for 1 h) for the Ti-Li and Ti-H centers. The dose recovery test confirmed that the proposed protocol works practically, and that the regenerative protocol is better than the additive dose protocol in the aspect of the statistical errors. Appropriate partial annealing conditions to extract the unbleachable Al centers may need to be investigated for each sample.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"180 ","pages":"Article 107327"},"PeriodicalIF":1.6,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lokendra Singh , P.Y. Bansode , Sabyasachi Paul , S.S. Ghodke , S.P. Borkar , S. Anand
{"title":"Development of a compact active neutron monitor to measure the H∗(10): Design, simulation and validation","authors":"Lokendra Singh , P.Y. Bansode , Sabyasachi Paul , S.S. Ghodke , S.P. Borkar , S. Anand","doi":"10.1016/j.radmeas.2024.107328","DOIUrl":"10.1016/j.radmeas.2024.107328","url":null,"abstract":"<div><div>The rapid advancement of radiation technology underscores the need for effective radiation protection and monitoring. Neutron dose equivalent (NDE) meters play a crucial role in measuring the ambient dose equivalent, <em>H</em>∗(10), in neutron radiation environments. However, traditional NDE meters, while effective, tend to be bulky and less suitable for use in anisotropic neutron fields and confined spaces. This study presents the development of a compact, portable NDE meter designed to overcome these challenges. The device, featuring a cylindrical design with a diameter of 14.8 cm, a length of 30.5 cm, and weighing under 4 kg, is optimized for ease of use in constrained spaces. It incorporates a BF<sub>3</sub> thermal neutron detector encased within a high-density polyethylene moderation assembly, calibrated to replicate ICRP-74 dose conversion coefficients. The design was optimized using Monte Carlo simulations using FLUKA, emphasizing neutron response uniformity and effective moderation. Experimental validation in standard neutron reference fields confirmed the accuracy of the simulated performance, with dose rate estimates deviating by less than 8% from reference values. The NDE meter's response was consistent with that of commercially available devices, showing relative energy response variations of less than 20% for both <sup>241</sup>Am-Be and <sup>252</sup>Cf sources. It demonstrated reliable energy response up to 5 MeV and consistent angular response (up to ∼ <span><math><mrow><mrow><mn>60</mn><mo>°</mo></mrow></mrow></math></span>), highlighting its potential for practical radiation protection applications in diverse and constrained environments.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107328"},"PeriodicalIF":1.6,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guldar Baubekova , Ruslan Assylbayev , Eduard Feldbach , Aleksei Krasnikov , Irina Kudryavtseva , Alise Podelinska , Viktor Seeman , Evgeni Shablonin , Evgeni Vasil'chenko , Aleksandr Lushchik
{"title":"Accumulation of oxygen interstitial-vacancy pairs under irradiation of corundum single crystals with energetic xenon ions","authors":"Guldar Baubekova , Ruslan Assylbayev , Eduard Feldbach , Aleksei Krasnikov , Irina Kudryavtseva , Alise Podelinska , Viktor Seeman , Evgeni Shablonin , Evgeni Vasil'chenko , Aleksandr Lushchik","doi":"10.1016/j.radmeas.2024.107324","DOIUrl":"10.1016/j.radmeas.2024.107324","url":null,"abstract":"<div><div>Single crystals of α-Al<sub>2</sub>O<sub>3</sub> with broad sides oriented perpendicular to the <em>c</em> crystal axis have been irradiated by 231-MeV xenon ions with fluence varying from 5 × 10<sup>11</sup> to 10<sup>14</sup> ions/cm<sup>2</sup>. The spectra of radiation-induced optical absorption (absorption of a pristine crystal is subtracted) have been decomposed into Gaussians serving as a measure of oxygen-related Frenkel defects (interstitial-vacancy pairs). The concentration of all structural defects considered – vacancy-type <em>F</em> and <em>F</em><sup>+</sup> centers as well as oxygen interstitials – continuously increases with ion fluence. Therefore, radiation-induced origin of elementary absorption bands at 5.6 and 6.6 eV tentatively ascribed earlier to charged and neutral oxygen interstitials has been proved for the first time. The concentrations of charged interstitials (in the form of superoxide ions) have been directly determined by the EPR method. The evolution of cathodoluminescence bands typical of self-trapped excitons (VUV band at 7.6 eV) and <em>F</em>-type defects (bands peaked around 3.0 and 3.8 eV) with the rise of Xe-ion-irradiation fluence has been measured and analyzed.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107324"},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Gel dosimetry: An overview of dosimetry systems and read out methods","authors":"Yves De Deene , Andrew Jirasek","doi":"10.1016/j.radmeas.2024.107321","DOIUrl":"10.1016/j.radmeas.2024.107321","url":null,"abstract":"<div><div>Gel dosimetry has emerged over the past three decades in response to a growing need in high-precision radiotherapy to assess, in three dimensions, the absorbed radiation dose, as would be administered in cancer patients.</div><div>Radiation-induced reaction mechanisms are dependent on the class of gel dosimeter, with four classes emerging as primary dosimeters for use in radiation therapy dose verification: (i) Fricke gel dosimeters contain a Fricke solution consisting of ammonium iron (II) sulfate in an acidic solution of sulfuric acid. In Fricke systems an oxidation of ferrous ions results in a change in the nuclear magnetic resonance (NMR) relaxation rate, which enables reading out Fricke gel dosimeters by use of MRI. The radiation-induced oxidation in Fricke gel dosimeters can also be visualized by adding a redox indicator. (ii) Polymer gel dosimeters exploit the radiation induced polymerization reaction of vinyl monomers and are predominantly read out by quantitative MRI or X-ray CT. (iii) Radiochromic dosimeters do not demonstrate a significant radiation-induced change in NMR properties but can be scanned by use of optical scanners (optical CT). In contrast to Fricke gel dosimeters, radiochromic gel dosimeters do not rely on the oxidation of a metal ion but exhibit a color change upon radiation. (iv) Radiofluorogenic dosimeters become fluorescent when exposed to ionizing radiation and can be read out with a planar scanning light beam.</div><div>Likewise, the imaging modality used to extract quantitative dose information depends on the class of dosimeter being used, and three primary imaging modalities have emerged in this context: quantitative MRI, x-ray CT, and optical CT imaging. The accuracy and precision of the dose information extracted from gel dosimetry systems depends on both the dosimetric properties of the gel dosimeters and the readout technique, and the optimal readout method depends on the gel dosimeter response.</div><div>Despite remaining an active field of research and illustrations of the application of gel dosimetry for the validation of clinical dose distributions, the utilization of gel dosimetry as a routine clinical dosimeter has been rather limited. However, with the introduction of new radiotherapy techniques that focus on organ motion compensation, new fractionation schemes, and extreme dose rates, the need for 3D radiation dosimetry is apparent. Even with the need for 3D dosimetry being apparent, gel dosimetry faces continued challenges in areas regarding the extraction of reproducible, accurate, and precise dose information.</div><div>This review paper focuses on an introduction to gel dosimeter classes; a detailed examination of the three readout techniques with emphasis on the achievable accuracy, precision, and optimization of readout parameters; an outlook on future applications in emerging new radiotherapy techniques. We note that the introduction of theragnostic hybrid MRI-Linacs that combine an MR","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107321"},"PeriodicalIF":1.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Karampiperi, Christopher L. Rääf, Christian Bernhardsson
{"title":"Evaluation of a portable OSL/IRSL reader for radiation dose assessment of NaCl pellets – In situ individualised screening during R/N emergencies","authors":"Maria Karampiperi, Christopher L. Rääf, Christian Bernhardsson","doi":"10.1016/j.radmeas.2024.107323","DOIUrl":"10.1016/j.radmeas.2024.107323","url":null,"abstract":"<div><div>Household salt, Sodium Chloride (NaCl), has been suggested as an appropriate material for retrospective and prospective optically stimulated luminescence (OSL) radiation dosimetry. The current paper investigates the potential application of NaCl pellets during a radiological and/or nuclear emergency, together with an existing portable reader, for application as a novel tool for <em>in situ</em> screening of individual doses in exposed populations.</div><div>The evaluation of the portable reader's performance was assessed based on OSL and infra-red stimulated luminescence (IRSL) methods and the results were compared to two research readers, Risø TL/OSL (DA-20 and DA-15). For the studied absorbed dose range (0.63–487 mGy), it was found that five pellets are needed in the portable reader to achieve a similar OSL signal magnitude as using one pellet in the two research readers. The OSL results of the three readers show similar minimum detectable dose (MDD) values and similar linear trends for the obtained OSL dose response curves, within the studied dose range. The IRSL results show a lower IRSL signal for the portable reader, leading to higher MDD values compared to the stationary readers. The MDD can reach down to 2.3 and 47 μGy, respectively, for OSL and IRSL measurements of NaCl with the SUERC portable reader.</div><div>Furthermore, sensitization tests show a dose dependent increase in the OSL and IRSL signals. In addition, the possibility of reading the same pellets more than once was confirmed through an advanced protocol, which combines multiple read-outs, and a time delay test. If a combination of OSL and IRSL measurements is applied, it is important to adjust the stimulation length if the first is OSL, while in the case that the first measurement is IRSL, the OSL signal is independent of the IRSL stimulation length.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107323"},"PeriodicalIF":1.6,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vo Hong Hai , Nguyen Quoc Hung , Nguyen Tri Toan Phuc , Masaharu Nomachi
{"title":"Contributions of cosmic-ray components to the HPGe gamma spectrometer background spectrum within the 0°–45° Zenith angle range","authors":"Vo Hong Hai , Nguyen Quoc Hung , Nguyen Tri Toan Phuc , Masaharu Nomachi","doi":"10.1016/j.radmeas.2024.107322","DOIUrl":"10.1016/j.radmeas.2024.107322","url":null,"abstract":"<div><div>This study investigates the contributions of various cosmic-ray-induced components to the energy response of a High-Purity Germanium (HPGe) gamma spectrometer within the 0°–45° zenith angle range. The analysis focuses on muons, neutrons, protons, electrons, positrons, and photons. It also examines the impact of particle showers induced by muons interacting with the lead chamber and reaching the HPGe detector. Utilizing the GEANT4 simulation toolkit, we provide a detailed examination of these components' influence on the spectrum. The results confirm that within this zenith angle range, muons account for approximately 91% of the recorded cosmic-ray induced energy spectrum and contribute 54.6% to the overall cosmic-ray-induced background spectrum. The study also highlights the significant role of showers, especially those resulting from muon interactions with the lead shielding, in shaping the low-energy spectrum below 3 MeV.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107322"},"PeriodicalIF":1.6,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P.K. Witter , B. Champine , A.S. Tamashiro , P. Maggi
{"title":"A Review of the Lawrence Livermore Nuclear Accident Dosimeter 1980s-present","authors":"P.K. Witter , B. Champine , A.S. Tamashiro , P. Maggi","doi":"10.1016/j.radmeas.2024.107309","DOIUrl":"10.1016/j.radmeas.2024.107309","url":null,"abstract":"<div><div>A Nuclear Accident Dosimetry program is a federal requirement for all facilities that have the potential to have a criticality accident. Personnel Nuclear Accident Dosimeter (PNAD) theory and analytical procedures are driven by various scientific needs and interacting regulations. A brief history of the status of USA Department of Energy (DOE) nuclear accident dosimetry regulations, recommendations, and performance testing criteria are given. Then, the history of the Lawrence Livermore National Laboratory (LLNL) PNAD is explored, including changes in the physical dosimeter and adjustments of the analysis method through the last four decades. Finally, the performance of LLNL’s PNAD at criticality accident intercomparison training exercises since 2009 is explored. In general, reported neutron doses have been within or close to DOE-STD-1098 performance criteria while reported gamma doses have been outside of DOE-STD-1098 performance criteria. Reported total absorbed doses have varied in meeting ANSI/HPS N13.3 and ANSI/HPS N13.3 (R2019) performance criteria. Dosimetry staff retirement and turnover have left historical knowledge gaps, yet provided opportunities within the NAD program at LLNL. This review paper serves as an overview of the history and status of the NAD program. Brief technical, procedural and programmatic recommendations to improve LLNL’s NAD program are given. Technical recommendations include investigating orientation factors through modeling or empirical experimentation, investigating gamma dosimetry methods for high-dose scenarios, and exploring other dosimetric methods for simpler, quicker NAD analysis. Procedural recommendations include better documentation of conversion factor (activity-to-fluence and fluence-to-dose) derivations and spectrum uses, and updated analysis spreadsheets or simple Graphic User Interfaces for dose calculations. Programmatic recommendations include formalized training for NAD analysts, and having multiple SMEs trained on the NAD program.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107309"},"PeriodicalIF":1.6,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lily Bossin , Riccardo Dal Bello , Jeppe Brage Christensen , Stefan Schischke , Silvia Motta , Michele Togno , Eduardo Gardenali Yukihara
{"title":"Performance of a BeO-based dosimetry system for proton and electron beam dose measurements","authors":"Lily Bossin , Riccardo Dal Bello , Jeppe Brage Christensen , Stefan Schischke , Silvia Motta , Michele Togno , Eduardo Gardenali Yukihara","doi":"10.1016/j.radmeas.2024.107310","DOIUrl":"10.1016/j.radmeas.2024.107310","url":null,"abstract":"<div><div>This study aims to evaluate the performance of the BeO-based myOSLchip system (RadPro International GmbH, Remscheid, Germany) for dosimetry of proton and electron radiotherapy beams. Although beryllium oxide (BeO) has been recognised as a promising material for luminescence dosimetry in radiotherapy, this research extends beyond material properties and examines the entire BeO-based dosimetry system, including the detector, holder, and readout components.</div><div>Packages of myOSLchip dosimeters were irradiated either in a (<span><math><mrow><mn>70</mn><mo>−</mo><mn>230</mn></mrow></math></span>) MeV proton beam or in a 16 MeV electron beam. The readouts were carried out using the portable myOSLchip reader. In the electron beam, tests on the precision, dose response up to 100 Gy and dose-rate effects of the system were carried out. In the proton beam, the system was tested for its dose response (up to 10 Gy), fading, and linear energy transfer (LET) response.</div><div>For proton irradiations, the myOSLchip BeO OSLDs exhibited stability within 2% over 135 days, as well as a linear dose response in the tested range, (<span><math><mrow><mn>0</mn><mo>.</mo><mn>1</mn><mo>−</mo><mn>10</mn></mrow></math></span>) Gy. The efficiency showed a reduction for proton beams with LET values (for water) above 0.6 keV/<span><math><mi>μ</mi></math></span>m, with up to 40% loss in efficiency at 4 keV/<span><math><mi>μ</mi></math></span>m. For the electron irradiations, they showed a linear dose–response up to 20 Gy and dose-rate independence, with a constant response at least up to 2.99 × 10<sup>5</sup> Gy s<sup>−1</sup>. Using individual dosimeter sensitivity correction, the precision for a single dosimeter was around 3.5% (standard deviation of the data of all dosimeters) and for a package comprising four dosimeters was 1.7% (standard deviation of the mean of the four dosimeters).</div><div>These findings suggest the myOSLchip system’s potential as a reliable alternative to existing dosimetry systems in clinical applications.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"179 ","pages":"Article 107310"},"PeriodicalIF":1.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142526728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}