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1. Cryopreserved Stem Cells Incur Damages Due To Terrestrial Cosmic Rays Impairing Their Integrity Upon Long-Term Storage

Author

P. Rocheteau, G. Warot, M. Chapellier, M. Zampaolo, F. Chretien, and F. Piquemal

Subjects
Medicine
Abstract

Stem cells have the capacity to ensure the renewal of tissues and organs. They could be used in the future for a wide range of therapeutic purposes and are preserved at liquid nitrogen temperature to prevent any chemical or biological activity up to several decades before their use. We show that the cryogenized cells accumulate damages coming from natural radiations, potentially inducing DNA double-strand breaks (DSBs). Such DNA damage in stem cells could lead to either mortality of the cells upon thawing or a mutation diminishing the therapeutic potential of the treatment. Many studies show how stem cells react to different levels of radiation; the effect of terrestrial cosmic rays being key, it is thus also important to investigate the effect of the natural radiation on the cryopreserved stem cell behavior over time. Our study showed that the cryostored stem cells totally shielded from cosmic rays had less DSBs upon long-term storage. This could have important implications on the long-term cryostorage strategy and quality control of different cell banks.

Published
2022
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3. Improved limits on $\beta^+$EC and ECEC processes in $^{74}$Se

Author

G. Warot, A. V. Rakhimov, Yu. Shitov, N. I. Rukhadze, I. Stekl, A. A. Klimenko, S. I. Konovalov, A. S. Barabash, E. Rukhadze, V. B. Brudanin, V.I. Umatov, Laboratoire Souterrain de Modane (LSM - UMR 6417), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, Double electron capture, 010308 nuclear & particles physics, Double-beta decay, Analytical chemistry, chemistry.chemical_element, Low-background HPGe detector, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], External source, 01 natural sciences, chemistry, Double beta decay, Excited state, 0103 physical sciences, 010306 general physics, Hpge detector, Nuclear Experiment, Selenium
Abstract

New limits on $\beta^+$EC and ECEC processes in $^{74}$Se have been obtained using a 600 cm$^3$ HPGe detector and an external source consisting of 1600 g of a natural selenium powder. For different $\beta^+$EC and ECEC transitions (to the ground and excited states) obtained limits are on the level $\sim (0.2-4.8)\times10^{19}$ yr at 90\% C.L. In particular, for the potentially resonant transition into the 1204.2 keV excited state of $^{74}$Ge a lower half-life limit of $1.1\times10^{19}$ yr at 90\% C.L. has been obtained. Possibility to increase the sensitivity of such measurements is discussed., Comment: 16 pages, 3 figures. arXiv admin note: text overlap with arXiv:hep-ex/0610046

Published
2020
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4. Searching for the $\beta^+$EC and EC/EC Decays of $^{74}$Se

Author

E. Rukhadze, V.I. Umatov, V. B. Brudanin, Yu. Shitov, S. I. Konovalov, I. Stekl, N. I. Rukhadze, A. S. Barabash, G. Warot, A. V. Rakhimov, A. A. Klimenko, Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
Hadron, Analytical chemistry, General Physics and Astronomy, lifetime: measured, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Water equivalent, 7. Clean energy, 01 natural sciences, energy: transition, background: low, double-beta decay: (0neutrino), Double beta decay, 0103 physical sciences, double-beta decay: (2neutrino), 010302 applied physics, Physics, 010308 nuclear & particles physics, selenium: lifetime, neutrino: Majorana: mass, neutrino: exchange, selenium: semileptonic decay, nucleus: transition, Excited state, Underground laboratory, Hpge detector, selenium: nuclide, experimental results
Abstract

International audience; Double beta decay (β$^{+}$EC, EC/EC) of $^{74}$Se was investigated at the Modane underground laboratory (LSM, France; 4800 m of water equivalent) using the OBELIX ultralow-background HPGe detector with a sensitive volume of 600 cm$^{3}$ and a sample of natural selenium with a mass of 1.6 kg containing ~0.89% (~14.24 g) of $^{74}$Se. The new experimental limits for β$^{+}$EC and EC/EC decays of $^{74}$Se to ground 0$^{+}$ and excited $2_{1}^{ + },$ 596 keV, and $2_{2}^{ + },$ 1204 keV states of $^{74}$Ge, were obtained from experimental data accumulated over 135 days.

Published
2020
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5. The Low-Background HPGE Γ-Spectrometer OBELIX for the Investigation of the Double Beta Decay to Excited States

Author

A. A. Klimenko, V. G. Egorov, E. Rukhadze, G. Warot, N. I. Rukhadze, P. Loaiza, Yu. Shitov, R. Hodák, I. Stekl, M. Zampaolo, F. Mamedov, F. Piquemal, E. A. Yakushev, and V. B. Brudanin

Subjects
Nuclear physics, Physics, Spectrometer, Double beta decay, Excited state, 010403 inorganic & nuclear chemistry, 01 natural sciences, 0104 chemical sciences, Semiconductor detector
Published
2017
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6. Investigation of $\beta^+$EC, EC/EC processes in $^{74}$Se

Author

G. Warot, A. V. Rakhimov, V. B. Brudanin, I. Stekl, N. I. Rukhadze, V. I. Umatov, E. Rukhadze, S. I. Konovalov, Yu. A. Shitov, A. A. Klimenko, A. S. Barabash, Laboratoire Souterrain de Modane (LSM - UMR 6417), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Materials science, 010308 nuclear & particles physics, Radiochemistry, selenium: lifetime, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, energy: transition, neutrino: exchange, background: low, nucleus: transition, selenium: semileptonic decay, Volume (thermodynamics), chemistry, double-beta decay: (0neutrino), Double beta decay, 0103 physical sciences, Underground laboratory, double-beta decay: (2neutrino), 010306 general physics, Hpge detector, selenium: nuclide, Selenium, experimental results
Abstract

International audience; Investigation of double beta decay processes (β+EC, EC/EC) of 74Se was performed at the Modane underground laboratory (LSM, France, 4800 m w.e.) using ultra low-background HPGe detector Obelix with sensitive volume of 600 cm3 and a sample of natural selenium with a mass of 1.6 kg, containing ∼0.89% (∼14.24 g) of 74Se. New experimental limits (at 90 % CL) on double beta decay transitions of 74Se to the ground and exited states of 74Ge were obtained from the preliminary calculation of experimental data accumulated in 135 days.

Published
2019
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7. Development of methods for the preparation of radiopure 82Se sources for the SuperNEMO neutrinoless double-beta decay experiment

Author

J. J. Evans, F. Perrot, Masaharu Nomachi, Jihane Maalmi, Dominique Breton, D. Duchesneau, P. Guzowski, Y. Lemière, X.R. Liu, R. Breier, S. Jullian, Hector Gomez, S. I. Konovalov, V. Egorov, F.A. Tashimova, Y. A. Ramachers, G. Claverie, B. Richards, V. B. Brudanin, J.P. Cesar, S. Torre, F. Mamedov, R. Salazar, Karol Holý, D. Waters, X. Sarazin, V. V. Timkin, V.I. Umatov, O.I. Kochetov, A. A. Mirsagatova, C. Vilela, A. V. Rakhimov, C. Hugon, Juergen Thomas, G. Eurin, I. Stekl, J. S. Ricol, J. Mott, I. I. Sadikov, A. S. Barabash, Lukas Fajt, D.V. Filosofov, H. Ohsumi, E. Rukhadze, T. Le Noblet, Ch. Bourgeois, Fedor Šimkovic, Igor Nemchenok, A. Huber, N.I. Rukhadze, A. Minotti, N.A. Mirzayev, L. Simard, A. Smetana, Vit Vorobel, S. Snow, P Pridal, J. Busto, A. Chopra, Z. J. Liptak, C. Cerna, G. Warot, Karol Lang, D. V. Karaivanov, H. Burešova, V. Kovalenko, M. Bongrand, E. Chauveau, Pavel P. Povinec, A. Žukauskas, A. Rebii, F. Nova, J. K. Sedgbeer, B. Morgan, A. Remoto, A. Basharina-Freshville, M. Kauer, R. B. Pahlka, Ruben Saakyan, F. Mauger, Guillaume Lutter, Karel Smolek, X. Garrido, B. Soulé, S. Calvez, A. A. Klimenko, G. Oliviéro, V.I. Tretyak, R. L. Flack, Michele Cascella, Vl. I. Tretyak, R. Hodák, S. Söldner-Rembold, Yu. Shitov, P. Loaiza, Ch. Marquet, B. Guillon, A.A. Smolnikov, M. Zampaolo, S. Blot, M. Spavorova, I. Moreau, E. Birdsall, V. Palušová, Joleen Pater, A. Jeremie, F. Piquemal, M. Macko, F. Delalee, S. De Capua, Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Rakhimov, A, Barabash, A, Basharina-Freshville, A, Blot, S, Bongrand, M, Bourgeois, C, Breton, D, Breier, R, Birdsall, E, Brudanin, V, Buresova, H, Busto, J, Calvez, S, Cascella, M, Cerna, C, Cesar, J, Chauveau, E, Chopra, A, Claverie, G, De Capua, S, Delalee, F, Duchesneau, D, Egorov, V, Eurin, G, Evans, J, Fajt, L, Filosofov, D, Flack, R, Garrido, X, Gomez, H, Guillon, B, Guzowski, P, Hodak, R, Holy, K, Huber, A, Hugon, C, Jeremie, A, Jullian, S, Karaivanov, D, Kauer, M, Klimenko, A, Kochetov, O, Konovalov, S, Kovalenko, V, Lang, K, Lemiere, Y, Le Noblet, T, Liptak, Z, Liu, X, Loaiza, P, Lutter, G, Maalmi, J, Macko, M, Mamedov, F, Marquet, C, Mauger, F, Minotti, A, Mirsagatova, A, Mirzayev, N, Moreau, I, Morgan, B, Mott, J, Nemchenok, I, Nomachi, M, Nova, F, Ohsumi, H, Oliviero, G, Pahlka, R, Pater, J, Palusova, V, Perrot, F, Piquemal, F, Povinec, P, Pridal, P, Ramachers, Y, Rebii, A, Remoto, A, Richards, B, Ricol, J, Rukhadze, E, Rukhadze, N, Saakyan, R, Sadikov, I, Salazar, R, Sarazin, X, Sedgbeer, J, Shitov, Y, Simkovic, F, Simard, L, Smetana, A, Smolek, K, Smolnikov, A, Snow, S, Soldner-Rembold, S, Soule, B, Spavorova, M, Stekl, I, Tashimova, F, Thomas, J, Timkin, V, Torre, S, Tretyak, V, Umatov, V, Vilela, C, Vorobel, V, Warot, G, Waters, D, Zampaolo, M, Zukauskas, A, and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
SuperNEMO, Technology, purification, ion exchange chromatography, SuperNEMO, LSM Modane, mass spectrometry, neutron activation analysis, purification, Selenium-82, measurement methods, Ion chromatography, chemistry.chemical_element, Selenium-82, fabrication, Mass spectrometry, 01 natural sciences, neutron activation analysi, NO, Neutrino Ettore Majorana Observatory, LSM Modane, double-beta decay: (0neutrino), Decantation, 0103 physical sciences, 0302 Inorganic Chemistry, Chemistry, Inorganic & Nuclear, Physical and Theoretical Chemistry, Neutron activation analysis, 010306 general physics, Nuclear Science & Technology, background: radioactivity, mass spectrometry, [PHYS]Physics [physics], Detection limit, Science & Technology, 010308 nuclear & particles physics, Radiochemistry, IMPURITIES, ion exchange chromatography, Contamination, Chemistry, chemistry, SPECTROMETRY, 13. Climate action, sulfur, Physical Sciences, ion: exchange, Inorganic & Nuclear Chemistry, selenium: production, selenium: nuclide, oxygen, Selenium, neutron activation analysis
Abstract

International audience; AbstractA radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8–54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.

Published
2019
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8. Characterization and long-term performance of the Radon Trapping Facility operating at the Modane Underground Laboratory

Author

J. Busto, F. Mamedov, T. Suchá, B. Soule, V.B. Brudanin, E. Rukhadze, P. Rulík, I. Svetlík, J. Macl, O.I. Kochetov, K. Smolek, J. Hůlka, D. Lalanne, M. Havelcová, F. Perrot, I. Štekl, G. Warot, R. Noel, P. Loaiza, Rastislav Hodak, M. Žaloudková, F. Piquemal, S. Jullian, J. Mizera, M. Zampaolo, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Nuclear and High Energy Physics, Compressed air, radon: absorption, chemistry.chemical_element, Soil science, Radon, tau: lifetime, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, dark matter, double-beta decay: (0neutrino), Double beta decay, 0103 physical sciences, germanium: detector, Orders of magnitude (data), Exponential decay, 010306 general physics, background: radioactivity, Background radiation, Physics, energy: high, 010308 nuclear & particles physics, force: van der Waals, temperature: gradient, radon: background, Semiconductor detector, chemistry, Activated charcoal, 13. Climate action, radiation: background, experimental results
Abstract

International audience; Radon is one of the main potential sources of background radiation for any rare event experiments like neutrinoless double beta decay or dark matter experiments. The Radon Trapping Facility (RTF) installed in 2004 at the Modane Underground Laboratory (LSM) has been running for nine years providing radon-purified air at a level of 10 mBq m−3 for several experiments. The radon suppression principle is based on a radon physical adsorption using cooled compressed air at −55 °C pumped through a column filled with the K48 activated charcoal. After disassembling of the RTF, the 2.6 m high charcoal column has been divided into several layers in order to study with different techniques the dynamic adsorption coefficient (the K-factor) as a function of the depth and the radon spatial trapping profile by measuring the 210Pb activity. It has been demonstrated that after almost a decade of running, the K-factor of the activated charcoal remains constant except for the first few cm of the column. Furthermore, it has been demonstrated that the mass activity of 210Pb as a function of the depth of the charcoal column exhibits an exponential decay profile. The radon mean retention time τ R of (47.6 ± 1.2) days and the radon mean free path of (28.9 ± 0.4) cm have been derived and found to be consistent at 1σ with the ones obtained from the K-factor study, i.e. from a total independent measurement. The radon suppression factor of the RTF of has been also estimated with a value consistent at 2σ with the suppression factor measured during the RTF operation. Thus, this study has proven the capacity of the RTF to purify the LSM air from radon by more than three orders of magnitude during nine years of operation.

Published
2019
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9. A novel combined countercurrent chromatography - inductively coupled plasma mass spectrometry method for the determination of ultra trace uranium and thorium in Roman lead

Author

D.V. Filosofov, E. Yakushev, Natalia N. Fedyunina, Petr S. Fedotov, G. Warot, Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
Detection limit, Chromatography, Elution, 010401 analytical chemistry, Extraction (chemistry), chemistry.chemical_element, Shields, Thorium, 02 engineering and technology, Uranium, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Analytical Chemistry, Countercurrent chromatography, chemistry, 0210 nano-technology, Inductively coupled plasma mass spectrometry
Abstract

International audience; The concentration of uranium and thorium in lead shields, which are used in underground particle physics research, should be monitored at sub-ppt levels. A combination of extraction chromatography and inductively coupled plasma mass spectrometry can resolve this analytical task. However, a multi-step complicated separation procedure and clean room are required. Besides, the recovery yields for U and Th do not exceed 80% and 60%, correspondingly. We propose an alternative approach. U and Th were pre-concentrated and separated from Pb by countercurrent chromatography, which is a support-free liquid-liquid chromatography. A series of two-phase extraction systems were tested. Under the optimized conditions, U and Th were extracted using a system 1 M HNO3/0.01 M tetraphenylmethylenediphosphine dioxide in chloroform and then eluted by 0.01 M aqueous solution of etidronic acid and determined by inductively coupled plasma mass spectrometry. The separation is performed in one chromatographic run, takes less than 1 h, and provides the quantitative recovery of U and Th. The limits of detection are 3 and 1 ppt for U and Th, correspondingly. The concentrations of U and Th in Roman lead, which was raised from the sea bottom, were lower than the limits of detection. It sounds unbelievable, nevertheless, the antique lead manufactured by Romans can indeed serve as a high-purity low-background material for the construction of Pb shields. Apart from the analysis of antique lead, the proposed approach can be easily extended to the determination of ultra trace impurities in different materials due to a very wide variety of two-phase extraction systems, which can be used in countercurrent chromatography.

Published
2018
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10. Investigating the Double Beta Decay of $^{58}$Ni

Author

A. A. Klimenko, V. B. Brudanin, F. Piquemal, I. Stekl, E. Rukhadze, N. I. Rukhadze, Yu. Shitov, G. Warot, Laboratoire Souterrain de Modane (LSM - UMR 6417), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], energy: ground state, Hadron, Analytical chemistry, energy spectrum, General Physics and Astronomy, Water equivalent, 7. Clean energy, 01 natural sciences, Preliminary analysis, energy: transition, nickel, double-beta decay: (0neutrino), Double beta decay, 0103 physical sciences, double-beta decay: (2neutrino), 010306 general physics, Physics, 010308 nuclear & particles physics, excited state: energy, semileptonic decay, 3. Good health, nucleus: transition, Excited state, Underground laboratory, Ground state, Hpge detector
Abstract

Double beta decay (β + EC, EC/EC) of 58Ni is investigated at France’s Modane Underground Laboratory (4800 m water equivalent) using the OBELIX ultralow-background HPGe detector with a sensitive volume of 600 cm3 and a natural nickel sample of ~68% 58Ni with a mass of ~21.7 kg. After preliminary analysis of the experimental data accumulated over ~144 days, new experimental limits are obtained for the 2νβ+EC decay of 58Ni to the 0+ ground state and the 2 1 + , 811 keV excited state of 58Fe, and for the 2νEC/EC decay of 58Ni to the 2 1 + , 811 keV and 2 2 + , 1675 keV excited states of 58Fe. The limits are T1/2(β+EC,0→0+) > 1.7 × 1022 yr, T1/2(β+EC,0→2 1 + ) > 2.3 × 1022 yr, T1/2(EC/EC,0→2 1 + ) > 3.3 × 1022 yr, and T1/2(EC/EC,0→2 2 + ) > 3.4 × 1022 yr. Experimental limit T1/2(0νEC/EC–res, 1918 keV > 4.1 × 1022 yr is obtained for resonant neutrinoless radiative EC/EC decay with an energy of 1918.3 keV. All limits are at 90% CL.

Published
2018
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11. Neutron activation analysis of polyethylene from neutron shield of EDELWEISS experiment

Author

Pia Loaiza, Dmitriy Medvedev, Ilkham I. Sadikov, Sergey V. Rozov, Genko M. Marinov, A. V. Rakhimov, N. M. Mukhamedshina, G. Warot, Evgeniy A. Yakushev, V. B. Brudanin, D.V. Filosofov, and A. A. Mirsagatova

Subjects
Nuclear physics, chemistry.chemical_compound, Chemistry, Shield, Radiochemistry, Neutron, Physical and Theoretical Chemistry, Polyethylene, EDELWEISS, Neutron activation analysis
Abstract

Instrumental neutron-activation analysis (INAA) was applied to estimate trace contaminations in polyethylene (PE) used as a neutron shield for low background setup of the EDELWEISS Dark Matter search experiment. PE samples with masses of 1–10 grams each were irradiated at the WWR-SM nuclear reactor by neutron flux of 1 · 1014 n/(cm2 s) for 5–48 h. The radioactivity was measured by high-resolution γ-ray spectrometry. In PE samples of two types, more than 30 trace elements were determined at a concentration level of 10−5 to 10 –11 g/g.

Published
2015
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12. Investigation of double beta decay of $^{58}$Ni at the Modane Underground Laboratory

Author

E. Rukhadze, N. I. Rukhadze, G. Warot, F. Piquemal, A. A. Klimenko, I. Stekl, Yu. Shitov, V. B. Brudanin, Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
History, 010308 nuclear & particles physics, Analytical chemistry, electron: capture, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Computer Science Applications, Education, talk: Sudbury 2017/07/24, nickel, double-beta decay: (0neutrino), Double beta decay, Excited state, 0103 physical sciences, Underground laboratory, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], 010306 general physics, Hpge detector, nucleus: excited state, experimental results, semiconductor detector: germanium
Abstract

Investigation of double beta decay processes (β+EC, EC/EC) of 58Ni was performed at the Modane underground laboratory (LSM, France, 4800 m w.e.). A sample of natural nickel, containing ∼68% of 58Ni and a mass of ∼21.7 kg, was measured using ultra low-background HPGe detector Obelix (sensitive volume of 600 cm3) during ∼143.8 days. New experimental limits on 2νβ+EC decay of 58Ni to the ground 0+ and (math), 811 keV excited state of 58Fe, and 2νEC/EC decay of 58Ni to (math), 811 keV and (maht), 1 675 keV excited states of 58Fe were obtained in this measurement. There are -T1/2(β+EC, 0+ → 0+) > 1.7 × 1022 y; (math), (math), (math). For resonant neutrino-less radiative EC/EC decay with energy of 1 918.3 keV a new experimental limit of T1/2 (0νEC/EC – res, 1918KeV) > 4.1 ×1022 y was also obtained. All limits are at 90 % CL.

Published
2017
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13. Investigation of double beta decay of $^{58}$Ni with the Obelix spectrometer

Author

F. Piquemal, N. I. Rukhadze, G. Warot, E. Rukhadze, A. A. Klimenko, Yu. Shitov, V. B. Brudanin, I. Stekl, Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
energy: ground state, Analytical chemistry, energy spectrum, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, energy: transition, nickel, double-beta decay: (0neutrino), Double beta decay, 0103 physical sciences, double-beta decay: (2neutrino), 010306 general physics, Physics, Spectrometer, 010308 nuclear & particles physics, excited state: energy, semileptonic decay, Nickel, nucleus: transition, chemistry, Excited state, Underground laboratory, spectrometer, Hpge detector
Abstract

International audience; Investigation of double beta decay processes (β+EC, EC/EC) of 58Ni was performed at the Modane underground laboratory (LSM, France, 4800 m w.e.) using ultra low-background HPGe detector Obelix with sensitive volume of 600 cm3 and a sample of natural nickel, containing ∼68% of 58Ni with a mass of ∼21.7 kg. New experimental limits on 2νβ+EC decay of 58Ni to the ground 0+ and 21+, 811 keV excited state of 58Fe, and 2νEC/EC decay of 58Ni to 21+, 811 keV and 22+ 1 675 keV excited states of 58Fe were obtained from the preliminary calculation of experimental data accumulated in ∼88d. They are - T1/2(β+ EC, 0+ → 0+) > 1.4 ×1021 y; T1/2(β+EC,0+→21+)>1.7×1022 y, T1/2(EC/EC, 0+→21+)>2.4×1022 y, T1/2(EC/EC, 0+→22+)>2.1×1022 y. For resonant neutrino-less radiative EC/EC decay with energy of 1 918.3 keV a new experimental limit of T1/2 (0νEC/EC − res, 1918keV) > 4.7 ×1022 y was also obtained. All limits are at 90 % CL.

Published
2017
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14. Purification of selenium from thorium, uranium, radium, actinium and potassium impurities for low background measurements

Author

G. Warot, A. V. Rakhimov, N. M. Mukhamedshina, O.I. Kochetov, N. A. Lebedev, I. I. Sadikov, D. V. Karaivanov, and D.V. Filosofov

Subjects
Radium, Actinium, Chemistry, Impurity, Potassium, Radiochemistry, chemistry.chemical_element, Thorium, Physical and Theoretical Chemistry, Uranium, Selenium
Abstract

Summary A technique of selenium purification from 232Th, 238U, 226,228Ra, 227Ac and 40K was developed. This technique is simple to perform and employs a minimum number of highly pure reagents (bidistilled water, nitric acid). Operations carried out during purification (elution, evaporation) practically exclude losses of the target product (chemical yields of Se > 99%). A test purification of 100 g of selenium was carried out using this technique. The efficiency of this technique was confirmed by low background gamma spectrometry of the purified selenium sample. Distribution coefficients of Th, U, Ra and Ac on DOWEX 50W-×8 cation-exchange resin at different concentrations of selenium and nitric acid were experimentally determinated. Instrumental neutron activation analysis of bidistilled water, deionized water and nitric acid was performed.

Published
2013
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15. A highly efficient HPGE gamma-ray spectrometer for investigating ββ decay to excited states

Author

G. Warot, F. Mamedov, I. Stekl, P. Čermák, Yu. Shitov, O.I. Kochetov, V. B. Brudanin, E. A. Yakushev, Ch. Briançon, F. Piquemal, M. Zampaolo, N. I. Rukhadze, E. Rukhadze, and P. Loaiza

Subjects
Physics, Decay scheme, Spectrometer, Physics::Instrumentation and Detectors, Electron capture, Gamma ray, General Physics and Astronomy, Resonance, Semiconductor detector, Nuclear physics, Excited state, Double beta decay, High Energy Physics::Experiment, Atomic physics, Nuclear Experiment
Abstract

A new low-background spectrometer based on a HPGe detector with a sensitive volume of 600 cm3 is developed to investigate rare nuclear processes such as resonance neutrinoless double electron capture and two-neutrino double beta decay to excited states of daughter nuclei. The spectrometer is installed at the Modane underground laboratory (France) at a depth of 4800 m w.e. The spectrometer background is measured and the spectrometer sensitivity is determined for measuring sources of double beta decay.

Published
2013
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16. Effect of recrystallisation on the radioactive contamination of CaWO4 crystal scintillators

Author

I.M. Solsky, G. Warot, S.S. Nagorny, F.A. Danevich, Stefano Nisi, V.B. Mikhailik, V. V. Kobychev, A. S. Nikolaiko, P. Loaiza, H. Kraus, Matthias Laubenstein, and Ian Bailiff

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Radiochemistry, chemistry.chemical_element, Crystal growth, Uranium, Scintillator, Crystal, chemistry, Radioactive contamination, Instrumentation, Single crystal, Order of magnitude
Abstract

Minimising intrinsic radioactivity of crystal scintillators is of particular importance for experiments searching for rare events. We studied the impact of the crystal production process (recrystallisation) on the level of radioactive contamination of CaWO4 crystal scintillators. Several samples of single crystal scintillators were produced using the recrystallisation procedure. It is shown that this has a significant effect on the radioactive contamination of the crystals. Depending on the stage of recrystallisation the activity due to 210Po (product of 210Pb decay) varies in the range 0.031.32 Bq kg-1 while the activity of 238U varies from 0.04 to 0.33 Bq kg-1. We found that uranium is rejected by the crystal with a segregation coefficient ≈0.3. The improvement in radiopurity of CaWO4 by one order of magnitude due to recrystallisation has been demonstrated. The additional benefit of this process is the improvement in the energy resolution. A programme to develop radiopure CaWO4 crystal scintillators is discussed briefly. © 2010 Elsevier B.V. All rights reserved.

Published
2016

17. Air radioactivity levels following the Fukushima reactor accident measured at the Laboratoire Souterrain de Modane, France

Author

F. Piquemal, J. L. Reyss, G. Warot, P. Loaiza, I. Stekl, V.B. Brudanin, M. Zampaolo, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Océan et Interfaces (OCEANIS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
010504 meteorology & atmospheric sciences, Health, Toxicology and Mutagenesis, 010501 environmental sciences, Poaceae, 01 natural sciences, Japan, Radiation Monitoring, Activity concentration, Fukushima Nuclear Accident, Environmental Chemistry, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Food Contamination, Radioactive, Waste Management and Disposal, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Radioisotopes, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Radionuclide, Fission products, Chemistry, Radiochemistry, General Medicine, Pollution, Radioactivity, Air Pollutants, Radioactive, 13. Climate action, France, Agaricales
Abstract

The radioactivity levels in the air of the radionuclides released by the Fukushima accident were measured at the Laboratoire Souterrain de Modane, in the South-East of France, during the period 25 March–18 April 2011. Air-filters from the ventilation system exposed for one or two days were measured using low-background gamma-ray spectrometry. In this paper we present the activity concentrations obtained for the radionuclides 131 I, 132 Te, 134 Cs, 137 Cs, 95 Nb, 95 Zr, 106 Ru, 140 Ba/La and 103 Ru. The activity concentration of 131 I was of the order of 100 μBq/m 3 , more than 100 times higher than the activities of other fission products. The highest activities of 131 I were measured as a first peak on 30 March and a second peak on 3–4 April. The activity concentrations of 134 Cs and 137 Cs varied from 5 to 30 μBq/m 3 . The highest activity concentration recorded for Cs corresponded to the same period as for 131 I, with a peak on 2–3 April. The results of the radioactivity concentration levels in grass and mushrooms exposed to the air in the Modane region were also measured. Activity concentrations of 131 I of about 100 mBq/m 2 were found in grass.

Published
2012
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18. Obelix, a new low-background HPGe at Modane Underground Laboratory

Author

G. Warot, E. Rukhadze, F. Piquemal, V.B. Brudanin, P. Loaiza, I. Stekl, M. Zampaolo, and N. I. Rukhadze

Subjects
Cryostat, Materials science, Detector, Radiochemistry, Electromagnetic shielding, Measuring instrument, Gamma spectroscopy, Isotopes of thorium, Particle detector, Semiconductor detector
Abstract

An ultra-low background coaxial HPGe detector for gamma-ray spectrometry with a relative efficiency of 160%, corresponding to a 600 cm3 Ge crystal, was installed at the Laboratoire Souterrain de Modane, France (4800 m.w.e). To reduce the instrinsic detector background, all parts involved in the detector cryostat were selected for their low radioactivity contamination. A shielding, composed of an inner layer of roman lead and an external layer of regular lead was installed, together with a system to reduce the Rn level inside the sample chamber. The shielding was designed to allow the measurement of Marinelli-shaped samples. We present the constructional details which lead to a remarkable low detector background of 73 cts/kg·d in [40, 3000] keV. Measured samples showed that sensitivities about 100 μBq/kg in 226Ra and 228Th are reached for samples of some kg and 30 days of lifetime.

Published
2015
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19. Tools for modeling radioactive contaminants in chip materials

Author

Ronald D. Schrimpf, Frédéric Wrobel, Antoine Touboul, Olivier Bruguier, A. Kaouache, G. Warot, Frédéric Saigné, Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Radiations et composants (RADIAC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Vanderbilt University [Nashville], Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
01 natural sciences, uranium, Reliability (semiconductor), 0103 physical sciences, radioactive contaminants, Materials Chemistry, Microelectronics, Electronics, Electrical and Electronic Engineering, radionuclide, Nuclear Experiment, 010306 general physics, Process engineering, 010308 nuclear & particles physics, business.industry, Contamination, specific activity, alpha pollutants, Condensed Matter Physics, Chip, Electronic, Optical and Magnetic Materials, SER, 13. Climate action, Environmental chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Physics::Accelerator Physics, Environmental science, Radioactive Pollutants, business
Abstract

Radioactive pollutants are naturally present in microelectronic device materials and can be an issue for the reliability of devices. The main concern is alpha emitters that produce high-energy particles (a few MeV) that ionize the semiconductor and then trigger soft errors. The question is to know what kinds of radionuclides are present in the device, their location in the device and the abundance of each species. In this paper we describe tools that are required to address the issue of radioactive pollutants in electronic devices.

Published
2017
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20. Investigation of double beta decay of 100Mo to excited states of 100Ru

Author

Frédéric Nowacki, C. Cerna, Pavel P. Povinec, J. Mott, Karel Smolek, Ph. Hubert, S. Blondel, O.I. Kochetov, C. Vilela, A. Žukauskas, B. Soulé, Vl.I. Tretyak, Fedor Šimkovic, C.S. Sutton, S. Jullian, J. J. Evans, V.B. Brudanin, L. Dragounová, Masaharu Nomachi, H. Gómez, V. Egorov, G. Eurin, A.A. Smolnikov, I. Stekl, Igor Nemchenok, A.J. Caffrey, Vit Vorobel, E. Chauveau, A. A. Klimenko, R. Hodák, S. Blot, V. I. Umatov, A. Smetana, R. Arnold, P. Guzowski, V. Kovalenko, Y. Lemière, R. Saakyan, F. Perrot, C. Augier, A. Chapon, S. I. Konovalov, X. Garrido, J. L. Reyss, P. Čermák, V. V. Timkin, S. Söldner-Rembold, R. B. Pahlka, A. S. Barabash, D. Duchesneau, M. Bongrand, Guillaume Lutter, J. Hůlka, Z. J. Liptak, Catherine Marquet, F. Nova, Karol Lang, E. Rukhadze, F. Mauger, B. Morgan, V.I. Tretyak, C. L. Riddle, A. Remoto, P. Loaiza, H. Ohsumi, Dominique Durand, A. Basharina-Freshville, Jouni Suhonen, D. Lalanne, Yu. Shitov, Juergen Thomas, G. Szklarz, L. Simard, F. Piquemal, Y. A. Ramachers, B. Richards, S. Torre, F. Mamedov, C. Hugon, X. Sarazin, D. Waters, G. Warot, N.I. Rukhadze, R. L. Flack, J. Busto, B. Guillon, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Neutrino et Faibles Radioactivités (NEMO), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Souterrain de Modane (LSM - UMR 6417), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Océan et Interfaces (OCEANIS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), NEMO-3, Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
Physics, Nuclear and High Energy Physics, Decay scheme, ta114, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], External source, 7. Clean energy, 3. Good health, Nuclear physics, Excited state, Excited nucleus, Double beta decay, Nuclear Experiment (nucl-ex), Atomic physics, Hpge detector, Nuclear Experiment
Abstract

Double beta decay of $^{100}$Mo to the excited states of daughter nuclei has been studied using a 600 cm$^3$ low-background HPGe detector and an external source consisting of 2588 g of 97.5% enriched metallic $^{100}$Mo, which was formerly inside the NEMO-3 detector and used for the NEMO-3 measurements of $^{100}$Mo. The half-life for the two-neutrino double beta decay of $^{100}$Mo to the excited 0$^+_1$ state in $^{100}$Ru is measured to be $T_{1/2}=[7.5 \pm{0.6}(stat) \pm {0.6}(syst)]\cdot 10^{20}$ yr. For other $(0\nu + 2\nu)$ transitions to the 2$^+_1$, 2$^+_2$, 0$^+_2$, 2$^+_3$ and 0$^+_3$ levels in $^{100}$Ru, limits are obtained at the level of $\sim (0.25-1.1)\cdot 10^{22}$ yr., Comment: 19 pages, 4 figures. arXiv admin note: text overlap with arXiv:0904.1924

Published
2014
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21. Low background germanium planar detector for gamma-ray spectrometry

Author

J. L. Reyss, P. Loaiza, A. Nachab, G. Warot, C. Chassaing, Ph. Hubert, F. Perrot, Laboratoire Souterrain de Modane (LSM - UMR 6417), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), CANBERRA France, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, Resolution (mass spectrometry), gamma-ray spectrometry, 010308 nuclear & particles physics, business.industry, Monte Carlo method, Detector, Gamma ray, Analytical chemistry, chemistry.chemical_element, Germanium, Low-background, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Optics, Planar, chemistry, 0103 physical sciences, 010306 general physics, business, Instrumentation, Monte Carlo simulation, Line (formation)
Abstract

A new ultra-low background planar germanium spectrometer has been developed. The planar geometry improves the sensitivity and energy resolution below 600 keV. The integral background counting rate in the Laboratoire Souterrain de Modane (4800 m water equivalent) in the energy range from 20 to 1500 keV for the planar Ge (mass=800 g) is 140 count/day. After 40 days of statistics, the background counting rates for all expected single lines are below 0.5 count/day with the exception of 210Pb(46-keV line) which was measured to be (1.76±0.25) count/day. Monte Carlo simulations have been performed to explain the origin of the remaining background and to calculate the detection efficiencies. Sensitivities around 1 mBq/kg are obtained within few days of statistics for 226Ra and 228Th. The main achievement is the high sensitivities for 210Pb (46-keV line) and 238U (234Th: 63 and 93 keV lines). For an aluminium sample (mass=1 kg) the limits obtained in 15 days are 210 Pb 9 mBq / kg and 238 U 3 mBq / kg .

Published
2011
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22. The Advantages of a Compact Filter for Individual or Semi-Collective Waste Water Treatment

Author

G. Warot, P. Vander Borght, and A. Fazio

Subjects
Engineering, Environmental Engineering, Waste management, business.industry, media_common.quotation_subject, Environmental engineering, Sand filter, Septic tank, Contamination, Work (electrical), Filter (video), Sewage treatment, Water treatment, business, Effluent, Water Science and Technology, media_common
Abstract

In certain rural areas, collective water treatment is not an economically viable solution due to the cost of the water collection facilities (difficult terrain, distance between the houses); for various reasons, however, the traditional individual water treatment system is not highly regarded (bad installation, insufficient maintenance, …) and thus, work has been carried out to develop a high-performance and compact alternative solution for domestic waste water treatment. This alternative system makes use of a compact sand filter installed downstream from the septic tank, the filter's performance is based on supply regulation and improvement of the waste's surface distribution. Hydraulic laboratory studies and follow-up on a testing stand using real effluent have enabled us to develop a standardized compact system which is suitable for use in most terrains. The filter's purification performance is outstanding; at a daily supply rate of 150 l/m2, the average purification yields are over 90 % for COD, BOD, NH4, NKT From the bacteriological point of view, bacterial contamination is also significantly reduced. Laboratory tests are being carried out at present, with the aim of further improving purification by inducing a denitrification process enabling reduction of nitrate levels. This system's compact overall dimensions and relatively low cost mean that it can be used not only for individual waste water treatment but also for effluent treatment for small communities (≤ 400 inhabitant equivalent).

Published
1993
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23. Soft-errors induced by terrestrial neutrons and natural alpha-particle emitters in advanced memory circuits at ground level

Author

S. Semikh, Jean-Luc Autran, Sebastien Martinie, S. V. Rozov, P. Roche, G. Warot, E. Yakushev, P. Loaiza, S. Sauze, Gilles Gasiot, S. Uznanski, Daniela Munteanu, M. Zampaolo, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Souterrain de Modane (LSM - UMR 6417), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Engineering, Nuclear engineering, Cosmic ray, Radiation, 01 natural sciences, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, 0103 physical sciences, Electronic engineering, Neutron, Static random-access memory, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Safety, Risk, Reliability and Quality, 010302 applied physics, business.industry, Alpha particle, Condensed Matter Physics, Chip, Atomic and Molecular Physics, and Optics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Characterization (materials science), Ground level, business
Abstract

21st European Symposium on the Reliability of Electron Devices, Failure Physics and Analysis (ESREF), Gaeta, ITALY, OCT 11-15, 2010; International audience; This review covers our recent (2005-2010) experiments and modeling-simulation work dedicated to the evaluation of natural radiation-induced soft errors in advanced static memory (SRAM) technologies. The impact on the chip soft-error rate (SER) of both terrestrial neutrons induced by cosmic rays and alpha-particle emitters, generated from traces of radioactive contaminants in CMOS process or packaging materials, has been experimentally investigated by life (i.e. real-time) testing performed at ground level on the Altitude Single-event Effect Test European Platform (ASTEP) and underground at the underground laboratory of modane (LSM). The paper describes these two test platforms and surveys the characterization results obtained for two SRAM technology nodes (130 nm and 65 nm). Experimental results concerning the characterization of the natural radiation environment are also reported. (C) 2010 Elsevier Ltd. All rights reserved.

Published
2010
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24. Alpha-emitter induced soft-errors in CMOS 130nm SRAM: Real-time underground experiment and Monte-Carlo simulation

Author

P. Loaiza, S. Sauze, Gilles Gasiot, J.L. Autran, Sebastien Martinie, S. Uznanski, Daniela Munteanu, G. Warot, Philippe Roche, and M. Zampaolo

Subjects
Physics, CMOS, Nuclear engineering, Monte Carlo method, Semiconductor device modeling, Electronic engineering, Proportional counter, Neutron, Secular equilibrium, Static random-access memory, Common emitter
Abstract

This work reports a long-duration (> 2 years) realtime characterization study of SRAM memories at the underground laboratory of Modane (LSM) to quantify alphaemitter radioactive impurities present in the circuit materials and responsible of soft-errors detected in absence of atmospheric neutrons. Experimental data have been obtained using ∼3.5 Gbit of SRAMs manufactured in CMOS 130 nm technology. In a second part of this work, the underground experiment is simulated using a Monte-Carlo code to extract the contamination level related to the disintegration chain of uranium in silicon at secular equilibrium. Results are finally compared to data obtained from experimental counting experiments using an ultra low background alpha-particle gas proportional counter.

Published
2010
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26. Tools for modeling radioactive contaminants in chip materials.

Author

F Wrobel, A Kaouache, F Saigné, A D Touboul, R D Schrimpf, G Warot, and O Bruguier

Subjects
MICROELECTRONICS, SEMICONDUCTORS, RADIOACTIVE substances, INTEGRATED circuits, RELIABILITY in engineering, POLLUTANTS, ELECTRONIC equipment
Abstract

Radioactive pollutants are naturally present in microelectronic device materials and can be an issue for the reliability of devices. The main concern is alpha emitters that produce high-energy particles (a few MeV) that ionize the semiconductor and then trigger soft errors. The question is to know what kinds of radionuclides are present in the device, their location in the device and the abundance of each species. In this paper we describe tools that are required to address the issue of radioactive pollutants in electronic devices. [ABSTRACT FROM AUTHOR]

Published
2017
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27. Search for Daily Modulation of MeV Dark Matter Signals with DAMIC-M.

Author

Arnquist I, Avalos N, Baxter D, Bertou X, Castelló-Mor N, Chavarria AE, Cuevas-Zepeda J, Dastgheibi-Fard A, De Dominicis C, Deligny O, Duarte-Campderros J, Estrada E, Gadola N, Gaïor R, Hossbach T, Iddir L, Kavanagh BJ, Kilminster B, Lantero-Barreda A, Lawson I, Lee S, Letessier-Selvon A, Loaiza P, Lopez-Virto A, McGuire KJ, Mitra P, Munagavalasa S, Norcini D, Paul S, Piers A, Privitera P, Robmann P, Scorza S, Settimo M, Smida R, Traina M, Vilar R, Warot G, Yajur R, and Zopounidis JP

Abstract

Dark matter (DM) particles with sufficiently large cross sections may scatter as they travel through Earth's bulk. The corresponding changes in the DM flux give rise to a characteristic daily modulation signal in detectors sensitive to DM-electron interactions. Here, we report results obtained from the first underground operation of the DAMIC-M prototype detector searching for such a signal from DM with MeV-scale mass. A model-independent analysis finds no modulation in the rate of 1  e^{-} events with sidereal period, where a DM signal would appear. We then use these data to place exclusion limits on DM in the mass range [0.53,2.7]  MeV/c^{2} interacting with electrons via a dark photon mediator. Taking advantage of the time-dependent signal we improve by ∼2 orders of magnitude on our previous limit obtained from the total rate of 1  e^{-} events, using the same dataset. This daily modulation search represents the current strongest limit on DM-electron scattering via ultralight mediators for DM masses around 1  MeV/c^{2}.

Published
2024
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28. First Constraints from DAMIC-M on Sub-GeV Dark-Matter Particles Interacting with Electrons.

Author

Arnquist I, Avalos N, Baxter D, Bertou X, Castelló-Mor N, Chavarria AE, Cuevas-Zepeda J, Gutiérrez JC, Duarte-Campderros J, Dastgheibi-Fard A, Deligny O, De Dominicis C, Estrada E, Gadola N, Gaïor R, Hossbach T, Iddir L, Khalil L, Kilminster B, Lantero-Barreda A, Lawson I, Lee S, Letessier-Selvon A, Loaiza P, Lopez-Virto A, Matalon A, Munagavalasa S, McGuire KJ, Mitra P, Norcini D, Papadopoulos G, Paul S, Piers A, Privitera P, Ramanathan K, Robmann P, Settimo M, Smida R, Thomas R, Traina M, Vila I, Vilar R, Warot G, Yajur R, and Zopounidis JP

Abstract

We report constraints on sub-GeV dark matter particles interacting with electrons from the first underground operation of DAMIC-M detectors. The search is performed with an integrated exposure of 85.23 g days, and exploits the subelectron charge resolution and low level of dark current of DAMIC-M charge-coupled devices (CCDs). Dark-matter-induced ionization signals above the detector dark current are searched for in CCD pixels with charge up to 7e^{-}. With this dataset we place limits on dark matter particles of mass between 0.53 and 1000  MeV/c^{2}, excluding unexplored regions of parameter space in the mass ranges [1.6,1000]  MeV/c^{2} and [1.5,15.1]  MeV/c^{2} for ultralight and heavy mediator interactions, respectively.

Published
2023
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29. Cryopreserved Stem Cells Incur Damages Due To Terrestrial Cosmic Rays Impairing Their Integrity Upon Long-Term Storage.

Author

Rocheteau P, Warot G, Chapellier M, Zampaolo M, Chretien F, and Piquemal F

Subjects
Cryopreservation, Gamma Rays, Stem Cells, DNA Breaks, Double-Stranded, DNA Damage
Abstract

Stem cells have the capacity to ensure the renewal of tissues and organs. They could be used in the future for a wide range of therapeutic purposes and are preserved at liquid nitrogen temperature to prevent any chemical or biological activity up to several decades before their use. We show that the cryogenized cells accumulate damages coming from natural radiations, potentially inducing DNA double-strand breaks (DSBs). Such DNA damage in stem cells could lead to either mortality of the cells upon thawing or a mutation diminishing the therapeutic potential of the treatment. Many studies show how stem cells react to different levels of radiation; the effect of terrestrial cosmic rays being key, it is thus also important to investigate the effect of the natural radiation on the cryopreserved stem cell behavior over time. Our study showed that the cryostored stem cells totally shielded from cosmic rays had less DSBs upon long-term storage. This could have important implications on the long-term cryostorage strategy and quality control of different cell banks.

Published
2022
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30. A novel combined countercurrent chromatography - inductively coupled plasma mass spectrometry method for the determination of ultra trace uranium and thorium in Roman lead.

Author

Fedotov PS, Fedyunina NN, Filosofov DV, Yakushev EA, and Warot G

Abstract

The concentration of uranium and thorium in lead shields, which are used in underground particle physics research, should be monitored at sub-ppt levels. A combination of extraction chromatography and inductively coupled plasma mass spectrometry can resolve this analytical task. However, a multi-step complicated separation procedure and clean room are required. Besides, the recovery yields for U and Th do not exceed 80% and 60%, correspondingly. We propose an alternative approach. U and Th were pre-concentrated and separated from Pb by countercurrent chromatography, which is a support-free liquid-liquid chromatography. A series of two-phase extraction systems were tested. Under the optimized conditions, U and Th were extracted using a system 1 M HNO 3 /0.01 M tetraphenylmethylenediphosphine dioxide in chloroform and then eluted by 0.01 M aqueous solution of etidronic acid and determined by inductively coupled plasma mass spectrometry. The separation is performed in one chromatographic run, takes less than 1 h, and provides the quantitative recovery of U and Th. The limits of detection are 3 and 1 ppt for U and Th, correspondingly. The concentrations of U and Th in Roman lead, which was raised from the sea bottom, were lower than the limits of detection. It sounds unbelievable, nevertheless, the antique lead manufactured by Romans can indeed serve as a high-purity low-background material for the construction of Pb shields. Apart from the analysis of antique lead, the proposed approach can be easily extended to the determination of ultra trace impurities in different materials due to a very wide variety of two-phase extraction systems, which can be used in countercurrent chromatography., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Published
2019
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31. Air radioactivity levels following the Fukushima reactor accident measured at the Laboratoire Souterrain de Modane, France.

Author

Loaiza P, Brudanin V, Piquemal F, Reyss JL, Stekl I, Warot G, and Zampaolo M

Subjects
Agaricales chemistry, Food Contamination, Radioactive analysis, France, Japan, Poaceae chemistry, Radiation Monitoring, Radioactivity, Air Pollutants, Radioactive analysis, Fukushima Nuclear Accident, Radioisotopes analysis
Abstract

The radioactivity levels in the air of the radionuclides released by the Fukushima accident were measured at the Laboratoire Souterrain de Modane, in the South-East of France, during the period 25 March-18 April 2011. Air-filters from the ventilation system exposed for one or two days were measured using low-background gamma-ray spectrometry. In this paper we present the activity concentrations obtained for the radionuclides (131)I, (132)Te, (134)Cs, (137)Cs, (95)Nb, (95)Zr, (106)Ru, (140)Ba/La and (103)Ru. The activity concentration of (131)I was of the order of 100 μBq/m(3), more than 100 times higher than the activities of other fission products. The highest activities of (131)I were measured as a first peak on 30 March and a second peak on 3-4 April. The activity concentrations of (134)Cs and (137)Cs varied from 5 to 30 μBq/m(3). The highest activity concentration recorded for Cs corresponded to the same period as for (131)I, with a peak on 2-3 April. The results of the radioactivity concentration levels in grass and mushrooms exposed to the air in the Modane region were also measured. Activity concentrations of (131)I of about 100 mBq/m(2) were found in grass., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Published
2012
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