Coincidence summing correction factors for 238U and 232Th decay series using the Monte Carlo method

[EN] Environmental samples analyzed in gamma spectrometry laboratories usually contain natural radionuclides such as 238U and 232Th. Using gamma spectrometry techniques is possible to estimate the activity of these radionuclides by measuring the gamma emissions of radionuclides belonging to their decay chain. Nonetheless, some of these radionuclides emit photons in cascade presenting Coincidence Summing (CS), which if not corrected, may affect the final activity quantification. The aim of this work is to apply the Monte Carlo method to calculate the True Summing Correction Factors (TSCFs) for 238U and 232Th decay series for different sample configurations (geometry and matrix) using the GEANT4 toolkit. In order to validate the results provided by GEANT4 using the RDM, the software TRUECOINC has been applied to calculate also the TSCFs. In addition, the influence of the geometry/matrix on the TSCFs is analyzed.The authors gratefully acknowledge financial support from the Catedra CSN-UPV Vicente Serradell, Spain as well as the Laboratorio de Radiactividad Ambiental (Universitat Politecnica de Valencia), Spain for the dedicated funding and resources to this research work under Grant no. FPI-2015-S2-1576Ordóñez-Ródenas, J.; Gallardo Bermell, S.; Ortiz Moragón, J.; Martorell Alsina, SS. (2019). Coincidence summing correction factors for 238U and 232Th decay series using the Monte Carlo method. Radiation Physics and Chemistry. 155:244-247. https://doi.org/10.1016/j.radphyschem.2018.09.013S24424715

Evaluation of a multiple linear regression model and SARIMA model in forecasting 7Be air concentrations

[EN] Forecasting the 7Be air concentration is a target value in analyzing fluctuations that could reveal important information on the motions of atmospheric air masses. In this study we first propose a Seasonal Autoregressive Integrated Moving Average (SARIMA) model with a historical data time window of eight years (2007-2014) to forecast 7Be activity. The other proposal is a Multiple Linear Regression (MLR) model for the same time period, in which the atmospheric and meteorological variables are used to forecast 7Be air concentrations. The forecasting performance of both models is evaluated by comparison with real 7Be air concentrations by out-of-sample tests for the 12 months of the year 2015. Considering the high explicative power and the consistently low accuracy of the measurements in the out-of-sample year, the proposed SARIMA model provides good forecasts of 7Be air concentrations. In contrast, the MLR model provides information on the significant meteorological variables that affect 7Be concentrations and could be useful to identify meteorological or atmospheric changes that could cause deviations in these concentrations.This study has been partially supported by the REM program of the Nuclear Safety Council of Spain (SRA/2071/2015/227.06). We are also grateful to the UPV's weather station for providing the atmospheric information used in this study.Bas Cerdá, MDC.; Ortiz Moragón, J.; Ballesteros Pascual, L.; Martorell Alsina, SS. (2017). Evaluation of a multiple linear regression model and SARIMA model in forecasting 7Be air concentrations. Chemosphere. 177:326-333. https://doi.org/10.1016/j.chemosphere.2017.03.029S32633317

Forecasting 7BE concentrations in surface air using time series analysis

[EN] 7Be is a cosmogenic radionuclide widely used as an atmospheric tracer, whose evaluation and forecasting can provide valuable information on changes in the atmospheric behavior. In this study, measurements of 7Be concentrations were made each month during the period 2007-2015 from samples of atmospheric aerosols filtered from the air. The aim was to propose a Seasonal Autoregressive Integrated Moving Average (SARIMA) model to develop an explanatory and predictive model of 7Be air concentrations. The Root Mean Square Error (RMSE) and the Adapted Mean Absolute Percentage Error (AMAPE) were selected to measure forecasting accuracy in identifying the best historical data time window to explain 7Be concentrations. A measure based on the variance of forecast errors was calculated to determine the impact of the model uncertainty on forecasts. We concluded that the SARIMA method is a powerful explanatory and predictive technique for explaining 7 Be air concentrations in a longterm series of at least eight years of historical data to forecast 7 Be concentration trends up to one year in advance.This study has been supported partially by the REM program of the Nuclear Safety Council of Spain (SRA/2071/2015/227.06).Bas Cerdá, MDC.; Ortiz Moragón, J.; Ballesteros Pascual, L.; Martorell Alsina, SS. (2017). Forecasting 7BE concentrations in surface air using time series analysis. Atmospheric Environment. 155:154-161. https://doi.org/10.1016/j.atmosenv.2017.02.021S15416115

Sequential determination of uranium and plutonium in soil and sediment samples by borate salts fusion

[EN] This study describes a rapid method for sequential determination of uranium and plutonium isotopes in soil and sediment samples and its application to the study of Anthropocene sedimentary records. Different pretreatment methods have been tested (open-vessel digestion, borate salts fusion and NaOH salt fusion) achieving the complete dissolution of the sample in case of fusion methods. LiBO2 and Li2B4O7 (80/20) flux was finally selected because a higher amount of sample can be analyzed (up to 5 g). Moreover, separation steps with extraction chromatographic resin UTEVA were optimized. Average recoveries obtained for uranium and plutonium were acceptable, 59% and 72% respectively, and relative bias were below +/- 15%. The time to complete the separation is approximately 11 h without ashing the samples and, consequently, it can be used in emergencies.The authors are grateful to the Universitat Politècnica de València for finantial support under the "Programa propio para la Formación de Personal Investigador (FPI) de la Universitat Politècnica de València - Subprograma 1". We also thank the Valencian Agency for Security and Emergency and the Generalitat Valenciana for their support in the "Convenio de colaboración entre la Agencia Valenciana de Seguridad y Respuesta a las Emergencias y la Universitat Politècnica de València para el Desarrollo del Plan de Vigilancia Radiológica en Emergencias". The research was also funded by the ANTROPICOSTA-2: Anthropocene sedimentary record of the coastal and marine areas of Northern Atlantic Iberia (RTI2018-095678-B-C21, MCIU/AEI/FEDER, UE) and HAREA-Coastal Geology Research Group (Basque Government, IT976-16) projects.Sáez-Muñoz, M.; Ortiz Moragón, J.; Martorell Alsina, SS.; Gómez-Arozamena, J.; Cearreta, A. (2020). Sequential determination of uranium and plutonium in soil and sediment samples by borate salts fusion. Journal of Radioanalytical and Nuclear Chemistry. 323(3):1167-1177. https://doi.org/10.1007/s10967-020-07028-5S116711773233Soppera N, Bossant M, Dupont E (2014) JANIS 4: an improved version of the NEA Java-based nuclear data information system. Nucl Data Sheets 120:294–296UNSCEAR (2010) Sources and effects of ionizing radiation. Volume I: sources: report to the general assembly, scientific annexes A and B. UNSCEAR 2008 report. United Nations Scientific Committee on the Effects of Atomic Radiation. United Nations sales publication E.10.XI.3. United Nations, New YorkWaters CN, Syvitski JPM, Gałuszka A, Hancock GJ, Zalasiewicz J, Cearreta A, Grinevald J, Jeandel C, McNeill JR, Summerhayes C, Barnosky A (2015) Can nuclear weapons fallout mark the beginning of the Anthropocene Epoch? Bull Atom Sci 71:46–57IAEA (2015) The Fukushima Daiichi accident, technical radiological consequences, vol 4. International Atomic Energy Agency, ViennaEPA (2012) EPA 402-R-12-006, radiological laboratory sample analysis guide for incident response—radionuclides in soil. U.S. Environmental Protection Agency, MontgomeryMietelski JW, Wojtycza J, Zalewski M, Kapała J, Tomankiewicz E, Gaca P (2018) Plutonium and thorium isotopes in the bottom sediments of some Mazurian Lakes (Poland). J Radioanal Nucl Chem 318:2389–2399Corcho-Alvarado JA, Diaz-Asencio M, Froidevaux P, Bochud F, Alonso-Hernández CM, Sanchez-Cabeza JA (2014) Dating young Holocene coastal sediments in tropical regions: use of fallout 239,240Pu as alternative chronostratigraphic marker. Quat Geochronol 22:1–10Waters CN, Zalasiewicz J, Summerhayes C, Barnosky AD, Poirier C, Gałuszka A, Cearreta A, Edgeworth M, Ellis EC, Ellis M, Jeandel C, Leinfelder R, McNeill JR, Richter DDB, Steffen W, Syvitski J, Vidas D, Wagreich M, Williams M, Zhisheng A, Grinevald J, Odada E, Oreskes N, Wolfe AP (2016) The Anthropocene is functionally and stratigraphically distinct from the Holocene. Science 351(6269):aad2622Zalasiewicz J, Waters CN, Summerhayes C, Wolfe AP, Barnosky AD, Cearreta A, Crutzen P, Ellis E, Fairchild IJ, Gałuszka A, Haff P, Hajdas I, Head MJ, Ivar do Sul JA, Jeandel C, Leinfelder R, McNeill JR, Neal C, Odada E, Oreskes N, Steffen W, Syvitski J, Vidas D, Wagreich M, Williams M (2017) The Working Group on the Anthropocene: summary of evidence and interim recommendations. Anthropocene 19:55–60Qiao J, Hou X, Miró M, Roos P (2009) Determination of plutonium isotopes in waters and environmental solids: a review. Anal Chim Acta 652:66–84Croudace I, Warwick P, Reading D, Russell B (2016) Recent contributions to the rapid screening of radionuclides in emergency responses and nuclear forensics. Trends Anal Chem 85:120–129Casacuberta N, Lehritani M, Mantero J, Masqué P, Garcia-Orellana J, Garcia-Tenorio R (2012) Determination of U and Th α-emitters in NORM samples through extraction chromatography by using new and recycled UTEVA resins. Appl Radiat Isot 70:568–573Lozano JC, Herranz M, Mosqueda F, Manjón G, Idoeta R, Quintana B, García-Tenorio R, Bolívar JP (2017) Low-level determination of Th-isotopes by alpha spectrometry. Part 2: evaluation of methods for dissolution of samples and for test sample preparation. J Radioanal Nucl Chem 314:2519–2529Jurečič S, Benedik L, Planinšek P, Nečemer M, Kump P, Pihlar B (2014) Analysis of uranium in the insoluble residues after decomposition of soil samples by various techniques. Appl Radiat Isot 87:61–65Luo M, Xing S, Yang Y, Song L, Ma Y, Wang Y, Dai X, Happel S (2018) Sequential analyses of actinides in large-size soil and sediment samples with total sample dissolution. J Environ Radioact 187:73–80Sahli H, Röllin S, Putyrskaya V, Klemt E, Balsiger B, Burger M, Corcho Alvarado JA (2017) A procedure for the sequential determination of radionuclides in soil and sediment samples. J Radioanal Nucl Chem 314:2209–2218Reading D, Croudace I, Warwick P, Britton R (2015) A rapid dissolution procedure to aid initial nuclear forensics investigations of chemically refractory compounds and particles prior to gamma spectrometry. Anal Chim Acta 900:1–9IAEA (2009) IAEA/AQ/11A, procedure for the rapid determination of Pu isotopes and Am-241 in soil and sediment samples by alpha spectrometry, IAEA analytical quality in nuclear applications series no. 11. International Atomic Energy Agency, ViennaCroudace I, Warwick P, Taylor R, Dee S (1998) Rapid procedure for plutonium and uranium determination in soils using a borate fusion followed by ion-exchange and extraction chromatography. Anal Chim Acta 371:217–225Maxwell S, Culligan B, Hutchison J, McAlister D (2015) Rapid fusion method for the determination of Pu, Np, and Am in large soil samples. J Radioanal Nucl Chem 305:599–608EPA (2014) EPA 402-R-14-004, rapid method for sodium hydroxide fusion of concrete and brick matrices prior to americium, plutonium, strontium, radium, and uranium analyses for environmental remediation following radiological incidents. U.S. Environmental Protection Agency, MontgomeryMaxwell S, Culligan B, Noyes G (2010) Rapid separation method for actinides in emergency soil samples. Radiochim Acta 98:793–800Galindo C, Mougin L, Nourreddine A (2007) An improved radiochemical separation of uranium and thorium in environmental samples involving peroxide fusion. Appl Radiat Isot 65:9–16EPA (2012) Rapid method for fusion of soil and soil-related matrices prior to americium, plutonium, and uranium analyses for environmental remediation following radiological incidents. U.S. Environmental Protection Agency, MontgomeryMantero J, Lehritane M, Hurtado S, García-Tenorio R (2010) Radioanalytical determination of actinoids in refractory matrices by alkali fusion. J Radioanal Nucl Chem 286:557–563Braysher E, Russell B, Woods S, García-Miranda M, Ivanov P, Bouchard B, Read D (2019) Complete dissolution of solid matrices using automated borate fusion in support of nuclear decommissioning and production of reference materials. J Radioanal Nucl Chem 321:183–196Wang H, Ni Y, Zheng J, Huang Z, Xiao D, Aono T (2019) Low-temperature fusion using NH4HSO4 and NH4HF2 for rapid determination of Pu in soil and sediment samples. Anal Chim Acta 1050:71–79Leorri E, Cearreta A, García-Artola A, Irabien MJ, Blake WH (2013) Relative sea-level rise in the Basque coast (N Spain): different environmental consequences on the coastal area. Ocean Coast Manag 77:3–13Absi A (2005) Evolución del impacto radiactivo ambiental en la ría de Huelva tras el cambio en la gestión de los residuos de las industrias de producción deácido fosfórico. Doctoral thesis, Seville UniversityMARLAP (2004) Part II: chapter 13. Sample dissolution, (volume II), EPA 402-B-04-001B. In: Multi-agency radiological laboratory analytical protocols manualHallstadius L (1984) A method for the electrodeposition of actinides. Nucl Instrum Methods 223:266–267Currie LA (1968) Limits for qualitative detection and quantitative determination. Application to radiochemistry. Anal Chem 40(3):586–59

Analysis of the evolution of gross alpha and gross beta activities in airborne samples in Valencia (Spain)

[EN] Gross alpha () and gross beta activities () were measured weekly in the airborne of the Universitat Politècnica de Valencia campus (in the east of Spain) during the period 2009¿2015 (7 years). The geometric mean values of weekly and were 0.53·10¿4 Bq m¿3 and 5.77·10¿4 Bq m¿3, respectively; with an average ratio of 0.097. This study highlights the heterogeneity of gross alpha and gross beta activities depending on the different periods of the year. Data show seasonal variations with the highest activity in summer months and the lowest one in winter months. Several atmospheric factors were considered in order to explain this intra-annual variation (wind speed, temperature, relative humidity, precipitations, dust content and prevailing wind directions). Multiple Linear Regression Analysis were performed in order to obtain information on significant atmospheric factors that affect gross ¿ and gross ß variability, which could be useful in identifying meteorological or atmospheric changes that could cause deviations in gross ¿ and gross ß activity depending on the seasons considered. Models obtained explain more than 60% of variability for global data, and also for winter and spring-autumn months. However, more research is needed to explain gross ¿ and gross ß variability in summer months, because the atmospheric factors considered in the MLR explain less than 35% of variability.This study has been partially supported by the REM program of the Nuclear Safety Council of Spain (SRA/2071/2015/227.06). We also thank the Universitat Politecnica de Valencia for financial support under "Programa propio para la Formacide de Personal Investigador (FPI) de la Universitat Politecnica de Valencia Subprograma 1". We are also grateful to the UPV's weather station for providing the atmospheric information used in this study.Sáez-Muñoz, M.; Bas Cerdá, MDC.; Ortiz Moragón, J.; Martorell Alsina, SS. (2018). Analysis of the evolution of gross alpha and gross beta activities in airborne samples in Valencia (Spain). Journal of Environmental Radioactivity. 183:94-101. https://doi.org/10.1016/j.jenvrad.2017.12.019S9410118

Intercomparison of full energy peak efficiency curves for an HPGe detector using MCNP6 and GEANT4

[EN] This work is focused on studying the capabilities of different Monte Carlo tools to complement the Full Energy Peak Efficiency (FEPE) calibration procedures of the Environmental Radioactivity Laboratory of the Universitat Politècnica de València, UPV. In this frame, detailed models of a High Purity Germanium detector have been implemented using MCNP6 and GEANT4. Accordingly, an inter-comparison with experimental values ensures the model validation and improves the analysis of the physics phenomena involved. The validation of the models is determined by a quantitative comparison between the simulated and the measured efficiencies over the energy range under study (59.54¿1836.01 keV). The results show discrepancies between both Monte Carlo tools for 139Ce, 88Y and 60Co as GEANT4 is able to simulate the coincidence summing effect of these radionuclides.The authors gratefully acknowledge the Catedra CSN-UPV Vicente Serradell, Spain as well as the Laboratorio de Radiactividad Ambiental (Universitat Politecnica de Valencia), Spain for the dedicated funding and resources to this research work under Grant no. FPI-2015-S2-1576.Ordóñez-Ródenas, J.; Gallardo Bermell, S.; Ortiz Moragón, J.; Sáez-Muñoz, M.; Martorell Alsina, SS. (2019). Intercomparison of full energy peak efficiency curves for an HPGe detector using MCNP6 and GEANT4. Radiation Physics and Chemistry. 155:248-251. https://doi.org/10.1016/j.radphyschem.2018.06.049S24825115

Rapid method for radiostrontium determination in milk in emergency situations using PS resin

[EN] This study describes a new and rapid procedure for radiostrontium determination in milk samples based on the use of plastic scintillation resins (PS resins). The proposed method reduces the time of analysis by at least 2 h by combining separation and measurement preparation into a single step and optimizing the pre-treatment steps. The method is robust and reproducible, with good total recoveries (65% on average) and a relative bias for total radiostrontium activity (Sr-89 + Sr-90) below 7%. The minimum detectable activity for 100 mL of milk sample measured for 60 min is about 0.34 Bq L-1. The proposed method can quantify radiostrontium content in 5 h, which makes it suitable for use in emergency situations.The authors are grateful to the Spanish Ministerio de Economia y Competitividad (MINECO) for financial support, under CTM2014-02020 and the Catalan Agencia de Gestio d'Ajuts Universitaris i de Recerca (AGAUR) for financial support, under 2014-SGR-1277. We should also like to thank the Universitat Politecnica de Valencia for finantial support under the "Programa propio para la Formacion de Personal Investigador (FPI) de la UniversitatPolitecnica de Valencia - Subprograma 100.Sáez-Muñoz, M.; Bagán, H.; Tarancón, A.; García, JF.; Ortiz Moragón, J.; Martorell Alsina, SS. (2018). Rapid method for radiostrontium determination in milk in emergency situations using PS resin. Journal of Radioanalytical and Nuclear Chemistry. 315(3):543-555. https://doi.org/10.1007/s10967-017-5682-3S5435553153International Atomic Energy Agency (2015) The fukushima daiichi accident, technical radiological consequences, vol 4. IAEA, ViennaInternational Atomic Energy Agency (2006) Environmental consequences of the chernobyl accident and their remediation: 20 years of experience, Report of the UN Chernobyl forum expert group “environment”, radiological assessment reports Series No. 8, IAEA, ViennaPovinec PP, Hirose K, Aoyama M (2013) Fukushima accident: radioactivity impact on the environment. Elsevier, ChinaCouncil Regulation (Euratom) 2016/52 of 15 January 2016 laying down maximum permitted levels of radioactive contamination of food and feed following a nuclear accident or any other case of radiological emergency, and repealing regulation (Euratom) No 3954/87 and commission regulations (Euratom) No 944/89 and (Euratom) No 770/90Vajda N, Kim CK (2010) Determination of radiostrontium isotopes: a review of analytical methodology. Appl Radiat Isot 68:2306–2326Brun S, Bessac S, Uridat D, Boursier B (2002) Rapid method for the determination of radiostrontium in milk. J Radioanal Nucl Chem 253(2):191–197Maxwell SL, Culligan BK (2009) Rapid method for determination of radiostrontium in emergency milk samples. J Radioanal Nucl Chem 279(3):757–760Kabai E, Hornung L, Savkin BT, Poppitz-Spuhler A, Hiersche L (2011) Fast method and ultra fast screening for determination of 90Sr in milk and dairy products. Sci Total Environ 410–411:235–240International Atomic Energy Agency (2013) Rapid simultaneous determination of 89Sr and 90Sr in milk: a procedure using cerenkov and scintillation counting, analytical quality in nuclear applications no. IAEA/AQ/27, IAEA, ViennaBagán H, Tarancón A, Rauret G, García JF (2011) Radiostrontium separation and measurement in a single step using plastic scintillators plus selective extractants application to aqueous sample analysis. Anal Chim Acta 686:50–56Barrera J, Tarancón A, Bagán H, García JF (2016) A new plastic scintillation resin for single-step separation, concentration and measurement of technetium-99. Anal Chim Acta 936:259–266Lluch E, Barrera J, Tarancón A, Bagán H, García JF (2016) Analysis of 210Pb in water samples with plastic scintillation resins. Anal Chim Acta 940:38–45Santiago L, Tarancón A, García JF (2016) Influence of preparation parameters on the synthesis of plastic scintillation microspheres and evaluation of sample preparation. Adv Powder Technol 27(4):1309–1317Savitzky A, Golay MJE (1964) Smoothing and differentiation of data by simplified least-squares procedures. Anal Chem 36:1627–1639Currie LA (1968) Limits for qualitative detection and quantitative determination. Application to radiochemistry. Anal Chem 40(3):586–593UNE 34829:1983, Determination of the calcium content of milkISO 12081:2010, IDF 36:2010, Milk—Determination of calcium content—titrimetric methodHeckel A, Vogl K (2009) Rapid method for determination of the activity concentrations of 89Sr and 90Sr. Appl Radiat Isot 67:794–796Kabai E, Savkin B, Mehlsam I, Poppitz-Spuhler A (2017) Combined method for the fast determination of pure beta emitting radioisotopes in food samples. J Radioanal Nucl Chem 311:1401–1408Eikenberg J, Beer H, Rüthi M, Zumsteg I, Vetter A (2005) Precise determination of 89Sr and 90Sr/90Y in various matrices: the LSC 3-window approach. LSC2005 Advances in Liquid Scintillation Spectrometry, Radiocarbon, AZ, pp 237–249Kim CK, Al-Hamwi A, Toervenyi A, Kis-Benedek G, Sansone U (2009) Validation of rapid method for the determination of radiostrontium in milk. Appl Radiat Isot 67:786–79

Aplicación de un modelo de detector BEGe en MCNP6 como apoyo a la realización de medidas por espectrometría gamma en un laboratorio en caso de emergencia nuclear o radiactiva

[ES] Uno de los problemas al medir actividades altas como las de un escenario de emergencia es la posible saturación del detector o la obtención un tiempo muerto de medición demasiado alto como para dar resultados fiables. Esto llevaría a repetir la medida en diferentes condiciones aumentando el tiempo de respuesta y, por consiguiente, el riesgo de exposición de los trabajadores del laboratorio. La tasa de cuentas medidas por el detector se puede controlar variando la distancia de la muestra al detector, así como utilizando diferentes volúmenes de fuente. Se ha desarrollado un modelo de Monte Carlo de un detector BEGe para analizar la respuesta en eficiencia del sistema para varias geometrías de medición (distancias y volúmenes). Las curvas de eficiencia total para muchas de las configuraciones utilizadas en el laboratorio se obtienen utilizando el código MCNP6 para un rango de energía de entre 59.5 keV y 1836.0 keV. Las simulaciones han permitido estimar la emisión gamma admisible para diferentes volúmenes de fuente (en matriz de agua) y distancias de muestra a detector que evite la saturación del mismo. Los resultados conducen a lograr un compromiso entre la geometría, la distancia y el tiempo de medición para una determinada condición en situaciones de emergencia. Se proporcionan tres casos de aplicación para explicar cómo funciona el enfoque propuesto.Los autores agradecen a la Cátedra CSN-UPV Vicente Serradell, así como al Laboratorio de Radiactividad Ambiental (Universitat Politècnica de València), por la financiación y los recursos dedicados a este trabajo de investigación en virtud de la subvención no. FPI-2015-S2-1576. Además, los autores agradecen a la Agencia Valenciana de Seguridad y Emergencias y a la Generalitat Valenciana por su apoyo en el "Convenio de colaboración entre la Agencia Valenciana de Seguridad y Respuesta a las Emergencias y la Universitat Politècnica de València para el Desarrollo del Plan de Vigilancia Radiológica en Emergencias¿ bajo la Subvención No. S7042000, 2018.Ordóñez, J.; Martorell Alsina, SS.; Gallardo Bermell, S.; Ortiz Moragón, J. (2019). Aplicación de un modelo de detector BEGe en MCNP6 como apoyo a la realización de medidas por espectrometría gamma en un laboratorio en caso de emergencia nuclear o radiactiva. Sociedad Nuclear Española. 1-8. http://hdl.handle.net/10251/180972S1

Estudio de la respuesta de un TLD100-HARSHAW mediante el código de Monte Carlo MCNP6

[ES] El código MCNP6 se ha utilizado para desarrollar un modelo de Monte Carlo del TLD100- HARSHAW, incluyendo una fuente colimada y un fantoma de agua con paredes de PMMA (ISO water slab phantom). Para calcular el kerma en aire y las dosis superficial Hp (0.07) y profunda Hp (10), se aplica un tally F6 (MeV/g). Este modelo permite obtener la función de respuesta relativa en energía (RRE) normalizada al 137Cs para haces de diferente calidad y ángulos de incidencia. La validación del modelo se lleva a cabo comparando datos simulados con experimentales utilizando diferentes calidades de haz de rayos-X de acuerdo con la norma ISO-4037-3. El código MCNP6 representa una herramienta muy útil para analizar las mediciones experimentales y a su vez para realizar calibraciones de TLDs sin necesidad de irradiarlos.Los autores agradecen a la Cátedra CSN-UPV Vicente Serradell, así como al Laboratorio de Radiactividad Ambiental (Universitat Politècnica de València), por la financiación y los recursos dedicados a este trabajo de investigación en virtud de la subvención no. FPI-2015-S2-1576.Ordóñez, J.; Gallardo Bermell, S.; Ortiz Moragón, J.; Martorell Alsina, SS. (2019). Estudio de la respuesta de un TLD100-HARSHAW mediante el código de Monte Carlo MCNP6. Sociedad Nuclear Española. 1-8. http://hdl.handle.net/10251/180958S1

Air radon equilibrium factor measurement in a Waste Water Pre-Treatment Plant

[EN] We analyze in this paper a Waste Water Pre-Treatment Plant (WWTP) located at the Mediterranean coast with air radon concentration above Spanish action level (600 Bq per cubic meter). This paper presents a method for radon equilibrium determination by gamma spectrometry measuring of the radon progeny concentrations in the air, in order to estimate WWTP workers effective dose more exactly. The method is based on simultaneous sampling of air through a filter paper and alpha spectrometry measurement of radon activity concentration in the air. According to the measured radon activity concentration in the air of 368 +/- 45 Bq/m(3) the equilibrium factor between radon and progenies is estimated to be F=0.27, which is in good agreement with expected values.Martinez-Ferri, JE.; Juste Vidal, BJ.; Ortiz Moragón, J.; Martorell Alsina, SS.; Verdú Martín, GJ. (2017). Air radon equilibrium factor measurement in a Waste Water Pre-Treatment Plant. Radiation Physics and Chemistry. 140:20-24. doi:10.1016/j.radphyschem.2017.03.011S202414