Radiation Measurements最新文献

{"title":"Enhancing the detection efficiency of the 3D positive ion detector","authors":"Hemapriya R ,&nbsp;Sureka CS ,&nbsp;Venkatraman P ,&nbsp;Paramaguru PV ,&nbsp;Alok J Verma ,&nbsp;Amol Bhagwat ,&nbsp;Jeevanram RK","doi":"10.1016/j.radmeas.2024.107350","DOIUrl":"10.1016/j.radmeas.2024.107350","url":null,"abstract":"<div><div>Enhancing the 3D positive ion detector's efficiency is the objective of this study. The detector finds numerous application in the fields of radiation biology, radiation dosimetry, radiation protection, radiation measurement etc. Generally, in 3D positive ion detector the cathode used is either high resistive glass or gold coated over ceramic glass. The detector efficiency has been reported as 2%_max with high resistive glass cathode material and 9.2%_max with gold coated ceramic glass. In the present study, we have significantly improved the detection efficiency by replacing these materials with an oxygen-free high conductivity (OFHC) copper cathode. This modification resulted in a substantial increase in the detector efficiency, reaching a maximum of 31.3%_max. The study also presents a comparison between this enhanced performance and the previously reported efficiencies demonstrating the effectiveness of using high conductivity materials to improve ion detection capabilities.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107350"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149806","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":"Compton-camera-based radiopharmaceutical imaging with an attenuation-corrected LM-MLEM reconstruction strategy","authors":"Yuan Ren ,&nbsp;Changran Geng ,&nbsp;Xue Yang ,&nbsp;Lijun Tang ,&nbsp;Feng Tian ,&nbsp;Xiaobin Tang","doi":"10.1016/j.radmeas.2025.107379","DOIUrl":"10.1016/j.radmeas.2025.107379","url":null,"abstract":"<div><div>Compton cameras have garnered attention in nuclear medicine due to their broad energy detection range and high efficiency, showing potential for imaging of various therapeutic and diagnostic isotopes and theranostics. However, a current limitation on the application of Compton cameras in nuclear medical imaging is the lack of a suitable method for correcting human tissue attenuation. This research aims to propose a precise system matrix probability model that explicitly considers the attenuation effect for correcting tissue attenuation in Compton imaging of radionuclides. The model calculates the probability of tissue attenuation between imaging space pixels and detector positions and is integrated into the calculation of the system matrix and sensitivity matrix within the list-mode maximum likelihood expectation maximization (LM-MLEM) algorithm. To validate this attenuation-corrected LM-MLEM (AC-LM-MLEM) algorithm, phantom studies were conducted using both GEANT4 simulations and experiments with [¹⁸F]FDG radiopharmaceutical and a 3D-CZT Compton camera, along with animal experiments on a Sprague Dawley rat. In the simulated imaging results on the phantom model, the AC-LM-MLEM algorithm closely match the prescribed spherical source activity distribution. In the imaging results of experiments, the highly radioactive areas reconstructed by the AC-LM-MLEM algorithm are largely consistent with the clinically used positron emission tomography/computed tomography (PET/CT) reconstruction results. Qualitative and quantitative analyses of the reconstruction results indicate that the proposed AC-LM-MLEM algorithm corrects effectively for tissue attenuation.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107379"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149295","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":"A thorough examination of concurrent measurements cosmic ray radiation and meteorological parameters with the support of machine learning","authors":"Ahmet Polatoğlu","doi":"10.1016/j.radmeas.2025.107375","DOIUrl":"10.1016/j.radmeas.2025.107375","url":null,"abstract":"<div><div>It is becoming increasingly important to monitor environmental radiation in order to prevent radiation risks, to understand solar activity and to have information about space weather. In this context, many countries have established environmental monitoring networks. The aim of this paper is to present alternative ways to continuously monitor cosmic radiation in the atmosphere. This study utilizes a Cosmic Ray Muon Detector (CRMD) and a Geiger-Müller (GM) counter to measure Cosmic Rays (CRs) in the atmosphere, providing complementary data from both devices to enhance the accuracy of measurements. A combination of various techniques and instruments is required to accurately measure CRs radiation levels in the atmosphere. The GM counter, first combined with the coincidence method by Bothe and Kolhörster in the late 1920s, is an important tool in the detection of ioniing radiation. In addition, the use of scintillation detectors in cosmic radiation detection systems has become widespread and offers improved sensitivity and accuracy. Scintillation detectors of cosmic ray muons are important in CRs research and help to measure the content of secondary particles produced in extensive air showers initiated by CRs. CRMD and GM counters are self-sufficient in taking all signal readings and sending them via computer. The measurements of the two systems were also evaluated with measurements of temperature, dew point temperature, relative humidity, absolute humidity and atmospheric pressure. Subsequently, regression and boosting models were applied to analyze the data. Thus, the effects of atmospheric parameters on cosmic radiation measurements were observed. This study includes preliminary results from a study conducted over approximately three months and compared with international neutron monitor data. The results show the applicability and full potential of the proposed system. This detector system can be easily and affordably installed and operated for educational and research purposes in high schools and universities.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107375"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149323","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":"Luminescence detectors at a laser-based electron accelerator","authors":"A. Cimmino ,&nbsp;I. Ambrožová ,&nbsp;Ž. Knežević ,&nbsp;M. Majer ,&nbsp;D. Horváth ,&nbsp;C.M. Lazzarini ,&nbsp;G.M. Grittani ,&nbsp;R. Truneček ,&nbsp;V. Olšovcová","doi":"10.1016/j.radmeas.2024.107367","DOIUrl":"10.1016/j.radmeas.2024.107367","url":null,"abstract":"<div><div>This work presents the first measurement of the radiation field at the Allegra Laser for Acceleration (ALFA) at the ELI Beamlines laser-driven user facility. During the commissioning of ALFA laser pulses (&lt;20 fs, 1 kHz, 1.5 TW) were carefully focused inside supersonic gas targets to generate an ultra-short (fs) ultra-relativistic (10 s of MeV) electron beam. The radiation field produced was pulsed, mixed, and with high instantaneous fluxes and high dose rates. While new dosimetric techniques are being developed, important efforts are being made to investigate the behavior of known dosimetry systems at laser accelerators. The secondary radiation field at ALFA was here characterized using a combination of different solid-state dosimetric systems: optically stimulated luminescence, thermoluminesce, and radiophotoluminescence dosimeters. Luminescence dosimeters offer several advantages for these applications. They are robust and relatively inexpensive. They can be easily adapted to be placed in vacuum and comply with clean room environment: important aspects when laser optics are involved. Compared to active systems, there are no electronics that require shielding from electromagnetic pulses present at laser-driven accelerators. This contribution presents the obtained experimental data focusing on the different detector responses and their suitability for measurements at laser-driven accelerators.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107367"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149807","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":"Editorial: Radiation measurements in advanced radiotherapy techniques - Can dose be the ‘good guy’?","authors":"Tomas Kron ,&nbsp;Anatoly Rosenfeld ,&nbsp;Eduardo G. Yukihara","doi":"10.1016/j.radmeas.2025.107383","DOIUrl":"10.1016/j.radmeas.2025.107383","url":null,"abstract":"","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107383"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378675","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":"Performance assessment of ionization chambers in standard diagnostic radiology beams through the determination of calibration coefficients","authors":"Olumide Olaife Akerele,&nbsp;Samuel Mofolorunsho Oyeyemi,&nbsp;David Olakanmi Olaniyi,&nbsp;Oluwadamilare Timothy Fashogbon,&nbsp;Francis Adole Agada,&nbsp;Sherif Olaniyi Kelani,&nbsp;Akinkunmi Emmanuel Ladapo,&nbsp;Ahmed Mohammed Shiyanbade,&nbsp;Bamidele Musbau Adeniran,&nbsp;Latifat Ronke Owoade","doi":"10.1016/j.radmeas.2024.107349","DOIUrl":"10.1016/j.radmeas.2024.107349","url":null,"abstract":"<div><div>Dosimetry laboratories use reference ionization chambers (ICs) as their primary instruments for measuring radiation doses. The ICs are designed to have defined and accurate response characteristics, making them suitable for calibrating radiation detectors in specific beam qualities. This study assesses six ionization chambers (Radcal 10X6-3CT, Radcal 10X6-M, Radcal 10X6-10, Radcal 10X6-6, Exradin A4, and FC-65-G1) in standard International Electrotechnical Commission (IEC) defined diagnostic beams [RQR, RQA, RQT, and RQR-M (W + Al)] at the Secondary Standard Dosimetry Laboratory (SSDL). Calibration coefficients were estimated to evaluate energy dependency and relative response deviations of the ICs. Results showed that most ICs tested had limited energy dependency in RQR, RQA, and RQT beams, with deviations under 5%, confirming their suitability for clinical dosimetry and reference calibration at the SSDL. The Radcal 10X6-M performed well in mammography beams, while the other ICs showed significant deviations (6%–107%) in RQR-M (W + Al), limiting their mammography use. A key finding is the extended applicability of certain ICs beyond their specified energy ranges, particularly the Radcal 10X6-3CT, Radcal 10X6-M, and Radcal 10X6-10, which performed well in a broader range of diagnostic beam energies. This study provides essential data for optimizing IC selection and calibration, and highlights the need for further development of energy-independent ICs for enhanced versatility across clinical settings.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107349"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149803","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":"Investigation of the effect of crystal dead layer on system performance in Single Photon Emission Computed Tomography: A Monte Carlo simulation study","authors":"Hilal Uslu Aynur ,&nbsp;Tuncay Bayram ,&nbsp;Anes Hayder ,&nbsp;Sonay Gedik","doi":"10.1016/j.radmeas.2024.107363","DOIUrl":"10.1016/j.radmeas.2024.107363","url":null,"abstract":"<div><div>One of the factors affecting image quality in SPECT (Single Photon Emission Computed Tomography) applications is the dead layer that forms over time in the scintillation crystal. In this study, we aimed to investigate the effect of dead layers in the NaI(Tl) scintillation crystal used in SPECT on system performance. The GATE simulation code, which is based on the GEANT4 toolkit and is widely recognized for its application in nuclear imaging simulations, was employed for this investigation. In the first step, the standard SPECT model was simulated, and the SPECT performance parameters (sensitivity, spatial resolution, energy resolution, and contrast) for low 140 keV (for <span><math><msup><mrow></mrow><mrow><mn>99</mn><mi>m</mi></mrow></msup></math></span>Tc), medium 167 keV (for ²⁰¹Tl), and high 364 keV (for ¹³¹I) gamma energies have been analyzed. Then, various thicknesses of dead layers on the crystal were simulated, and the effect of the dead layer on the performance parameters was evaluated for the same energies. The results indicate a reduction in SPECT sensitivity of approximately 33.5%, 27.1%, and 21.7% for low, medium, and high energies, respectively, as the thickness of the crystal’s dead layer increases from 0.19 mm to 1.52 mm (equivalent to 2% to 16%). Small deteriorations in spatial resolution and energy resolution of the SPECT have been determined for 140 keV, 167 keV, and 364 keV gamma energies. The dead layers slightly influenced the contrast of SPECT. The results of this study show that the image quality assessment parameters of the SPECT system deteriorated as the thickness of the scintillation crystal’s dead layer increased.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107363"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149319","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":"Charge carrier release mechanisms underlying the emission of alkali feldspar infrared stimulated luminescence","authors":"Owen M. Williams,&nbsp;Nigel A. Spooner","doi":"10.1016/j.radmeas.2024.107362","DOIUrl":"10.1016/j.radmeas.2024.107362","url":null,"abstract":"<div><div>Within a recent experimental study we reported that ultraviolet measurements of infrared stimulated luminescence (IRSL) from a variety of alkali feldspars are characterised by the common presence of fast and slow pulse components. We interpreted our observations as indicating the presence of charge carrier processes associated respectively with electrons and alkali ions. Within our present study we utilise the defect pair model we have employed within earlier quartz studies in order to seek physical explanations for the underlying mechanisms. For this purpose, we argue that the most likely source defect is a trivalent charge-compensated titanium dimer. Within our model, we propose complementary defect reaction pairs that involve the respective release of electrons and alkali ions. Our analysis, which is concentrated on the charge carrier release mechanisms, involves the construction of appropriate configurational coordinate diagrams which we utilise in order to explain the origin of the fast and slow IRSL components and also that of infrared photoluminescence (IRPL).</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107362"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149320","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":"Scintillating structures of GaN on sapphire for hadron irradiation dosimetry","authors":"T. Ceponis ,&nbsp;L. Deveikis ,&nbsp;V. Kovalevskij ,&nbsp;V. Rumbauskas ,&nbsp;E. Gaubas","doi":"10.1016/j.radmeas.2025.107372","DOIUrl":"10.1016/j.radmeas.2025.107372","url":null,"abstract":"<div><div>Crystals of GaN and layered structures of GaN deposited on sapphire and on other substrates are promising in fabricating radiation hard dosimeters capable of functioning in the rather wide range (10¹¹- 10¹⁵ particle/cm²) of fluences. These structures are suitable for recording double response (electrical and optical) signals. The dynamic range of fluence estimation of the irradiation source potential in the creation of various radiation defects related to accumulated doses depends on the stopping range of definite detector materials. It is limited by the increased density of radiation defects in GaN and sapphire layers as a function of fluence. While penetrative particle irradiations are capable of exciting electronic transitions in sapphire substrates via radiation induced coloured F^±-centres composed of electron captured at an anion vacancy. Such a layered GaN/sapphire structure enables enhancement of the range of dosimetry fluence when scintillation and electrical responses are simultaneously collected from both GaN and Al₂O₃ materials. Moreover, GaN on Al₂O₃ fluence meters are solar-blind and insusceptible to IR noise. The simultaneous analysis of fluence dependent scintillation and microwave-probed photoconductivity characteristics have been examined in this study to highlight the beneficial mechanisms of radiative and non-radiative processes in order to produce the wide-range and radiation hard dosimeters. The possibilities and regimes of contactless recording of the electrical and scintillation signals by combining the microwave and optical probes have been demonstrated. Such a double–response fluence dosimetry can be implemented using both the in situ irradiation and post irradiation measurement regimes.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107372"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149324","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":"Criticality accident dosimetry with human blood: The dicentric chromosome assay and the neutron activation as complementary techniques","authors":"Daniela Ekendahl ,&nbsp;Jakub Vávra ,&nbsp;Miroslav Hýža ,&nbsp;Ondřej Huml ,&nbsp;Lukáš Kotík ,&nbsp;Johana Alaverdyan ,&nbsp;Artur Sergunin ,&nbsp;Marie Davídková ,&nbsp;Dana Kurková ,&nbsp;Zina Čemusová","doi":"10.1016/j.radmeas.2024.107365","DOIUrl":"10.1016/j.radmeas.2024.107365","url":null,"abstract":"","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107365"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149810","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}