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Düllmann CE, Artes E, Dragoun A, Haas R, Jäger E, Kindler B, Lommel B, Mangold KM, Meyer CC, Mokry C, Munnik F, Rapps M, Renisch D, Runke J, Seibert A, Stöckl M, Thörle-Pospiech P, Trautmann C, Trautmann N, Yakushev A. Advancements in the fabrication and characterization of actinide targets for superheavy element production. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08631-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractThe heaviest elements can exclusively be produced in actinide-target based nuclear fusion reactions with intense heavy-ion beams. Ever more powerful accelerators deliver beams of continuously increasing intensity, which brings targets of current technology to their limits and beyond. We motivate efforts to produce targets with improved properties, which calls for a better understanding of targets produced by molecular plating, the current standard method. Complementary analytical methods will help shedding more light on their chemical and physical changes in the beam. Special emphasis is devoted to the aspect of the optimum target thickness and the choice of the backing material.
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Heesen C, Mokry C, Salmen A, Hegen H, Mäurer M, Warnke C, Gehring K, Berthele A, Meier U. German guideline for diagnosis and treatment of multiple sclerosis – a survey focusing neurologists in daily practise. Mult Scler Relat Disord 2022; 63:103828. [DOI: 10.1016/j.msard.2022.103828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 04/21/2022] [Indexed: 11/29/2022]
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3
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Mokry C, Warnke C, Gehring K, Hegen H, Salmen A, Kraemer M, Kleiter I, Fasshauer E, Scheiderbauer J, Lühmann D, Köpke S, Berthele A, Heesen C. Implementation study of the 2021 German guideline for diagnosis and treatment of multiple sclerosis. Mult Scler Relat Disord 2021; 57:103434. [PMID: 34920249 DOI: 10.1016/j.msard.2021.103434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/19/2021] [Accepted: 11/27/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND In May 2021, a new guideline on the diagnosis and treatment of multiple sclerosis and related disorders was released in Germany. Since the success of a guideline depends on how it integrates into everyday clinical practice, the German Society for Neurology (DGN) has launched a multimethod implementation project. Here we report on the results based on the consultation version of the guideline. METHODS We used qualitative and quantitative data analyses to capture the nature and extent of barriers and facilitating factors to the implementation. We centered on the guideline's chapter A on diagnosis, relapse therapy, and immunotherapy of multiple sclerosis. We performed nine online focus group discussions and a web-based survey and analyzed emails and letters with comments from stakeholders and independent parties that were sent spontaneously or by invitation. RESULTS 94 neurologists answered the survey, and ≥70% agreed with the recommendations of the guideline on each major content topic. Barriers to implementation were detected in group discussions and written input. The most controversial issues of the guideline were "early treatment", "criteria for starting or switching therapy", "stepwise escalation versus early aggressive treatment", "classification of drugs into three categories of efficacy" and the scenarios on "treatment cessation". Some appreciated the highly structured recommendations, but others felt that the guideline restricts the free choice of therapy, or they were afraid of recourse claims. Some considered the guideline as too cautious regarding treatment initiation, possibly delaying necessary therapies. Others appreciated that conflicts of interests of the guideline's authoring group were minimized and thought that the new guideline is clearer, more extensive and practical. CONCLUSION In contrast to the survey, feedback in the focus group discussions and from individuals was diverse and sometimes more critical. Based on the overall feedback rate of about 250 people in relation to the number of 6500 board-certified neurologists in Germany, the overall appreciation of the guideline can only be considered as an indicator and not proof of acceptance. Results of this analysis were incorporated into several adjustments to the final guideline of 2021. Since the guideline is to be updated regularly under the auspices of a "living guideline", active interaction with users will continue to matter and help to improve it.
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Affiliation(s)
- C Mokry
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Institute of Neuroimmunology and Multiple Sclerosis (INIMS), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - C Warnke
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - K Gehring
- Neurocentre at Klosterforst, Itzehoe, Germany
| | - H Hegen
- Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - A Salmen
- Department of Neurology, Inselspital, Bern University Hospital, Bern, Switzerland
| | - M Kraemer
- Department of Neurology, Alfried Krupp Hospital Essen, Essen, Germany; Department of Neurology, Medical Faculty, Heinrich Heine University Duesseldorf, Duesseldorf, Germany
| | - I Kleiter
- Marianne-Strauß-Klinik, Behandlungszentrum Kempfenhausen für Multiple Sklerose Kranke gemeinnützige GmbH, Germany
| | - E Fasshauer
- German Multiple Sclerosis Society (DMSG), Bundesverband e.V., Hannover, Germany
| | - J Scheiderbauer
- Stiftung für Selbstbestimmung und Selbstvertretung von MS-Betroffene, Trier, Germany
| | - D Lühmann
- Department of Family medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - S Köpke
- Department for Nursing Sciences, Medical Faculty, University of Cologne, Cologne, Germany
| | - A Berthele
- School of Medicine, Dept. Of Neurology, Technical University Munich, Klinikum rechts der Isar, Munich, Germany
| | - C Heesen
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Institute of Neuroimmunology and Multiple Sclerosis (INIMS), University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Götz M, Götz S, Kratz JV, Ballof J, Düllmann CE, Eberhardt K, Mokry C, Renisch D, Runke J, Sato TK, Thörle-Pospiech P, Trautmann N, Yakushev A. Gas phase synthesis of 4d transition metal carbonyl complexes with thermalized fission fragments in single-atom reactions. RADIOCHIM ACTA 2021. [DOI: 10.1515/ract-2020-0052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The formation of carbonyl complexes using atom-at-a-time quantities of short-lived transition metals from fusion and fission reactions was reported in 2012. Numerous studies focussing on this chemical system, which is also applicable for the superheavy elements followed. We report on a novel two-chamber approach for the synthesis of such complexes that allows spatial decoupling of thermalization and gas-phase carbonyl complex synthesis. Neutron induced fission on 235U and spontaneous fission of 248Cm were employed for the production of the fission products. These were stopped inside a gas volume behind the target and flushed with an inert-gas flow into a second chamber. This was flushed with carbon monoxide to allow the gas-phase synthesis of carbonyl complexes. Parameter studies of the transfer from the first into the second chamber as well as on the carbonyl complex formation and transport processes have been performed. High overall efficiencies of more than 50% were reached rendering this approach interesting for studies of superheavy elements. Our results show that carbonyl complex formation of thermalized fission products is a single-atom reaction, and not a hot-atom reaction.
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Affiliation(s)
- Michael Götz
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- GSI Helmholtz Centre for Heavy Ion Research , 64291 Darmstadt , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Stefan Götz
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- GSI Helmholtz Centre for Heavy Ion Research , 64291 Darmstadt , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Jens-Volker Kratz
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
| | - Jochen Ballof
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- CERN , 1217 Meyrin , CH , Switzerland
| | - Christoph E. Düllmann
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- GSI Helmholtz Centre for Heavy Ion Research , 64291 Darmstadt , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Klaus Eberhardt
- Research Reactor TRIGA Mainz, Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
| | - Christoph Mokry
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Dennis Renisch
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Jörg Runke
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- GSI Helmholtz Centre for Heavy Ion Research , 64291 Darmstadt , DE , Germany
| | | | - Petra Thörle-Pospiech
- Department of Chemistry – TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
- Helmholtz Institute Mainz , 55099 Mainz , DE , Germany
| | - Norbert Trautmann
- Research Reactor TRIGA Mainz, Johannes Gutenberg University Mainz , 55099 Mainz , DE , Germany
| | - Alexander Yakushev
- GSI Helmholtz Centre for Heavy Ion Research , 64291 Darmstadt , DE , Germany
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5
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Såmark-Roth A, Cox DM, Rudolph D, Sarmiento LG, Carlsson BG, Egido JL, Golubev P, Heery J, Yakushev A, Åberg S, Albers HM, Albertsson M, Block M, Brand H, Calverley T, Cantemir R, Clark RM, Düllmann CE, Eberth J, Fahlander C, Forsberg U, Gates JM, Giacoppo F, Götz M, Götz S, Herzberg RD, Hrabar Y, Jäger E, Judson D, Khuyagbaatar J, Kindler B, Kojouharov I, Kratz JV, Krier J, Kurz N, Lens L, Ljungberg J, Lommel B, Louko J, Meyer CC, Mistry A, Mokry C, Papadakis P, Parr E, Pore JL, Ragnarsson I, Runke J, Schädel M, Schaffner H, Schausten B, Shaughnessy DA, Thörle-Pospiech P, Trautmann N, Uusitalo J. Spectroscopy along Flerovium Decay Chains: Discovery of ^{280}Ds and an Excited State in ^{282}Cn. Phys Rev Lett 2021; 126:032503. [PMID: 33543956 DOI: 10.1103/physrevlett.126.032503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/03/2020] [Indexed: 06/12/2023]
Abstract
A nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z=114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions ^{48}Ca+^{242}Pu and ^{48}Ca+^{244}Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to ^{286}Fl and ^{288}Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely ^{282}Cn. Spectroscopy of ^{288}Fl decay chains fixed Q_{α}=10.06(1) MeV. In one case, a Q_{α}=9.46(1)-MeV decay from ^{284}Cn into ^{280}Ds was observed, with ^{280}Ds fissioning after only 518 μs. The impact of these findings, aggregated with existing data on decay chains of ^{286,288}Fl, on the size of an anticipated shell gap at proton number Z=114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.
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Affiliation(s)
- A Såmark-Roth
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - D M Cox
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - D Rudolph
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - L G Sarmiento
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - B G Carlsson
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - J L Egido
- Departamento de Física Teórica and CIAFF, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - P Golubev
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - J Heery
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - A Yakushev
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - S Åberg
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - H M Albers
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - M Albertsson
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - M Block
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - H Brand
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - T Calverley
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - R Cantemir
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - R M Clark
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Ch E Düllmann
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Eberth
- Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
| | - C Fahlander
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - U Forsberg
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - J M Gates
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - F Giacoppo
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
| | - M Götz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - S Götz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - R-D Herzberg
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - Y Hrabar
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - E Jäger
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - D Judson
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - J Khuyagbaatar
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, 55099 Mainz, Germany
| | - B Kindler
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - I Kojouharov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - J V Kratz
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Krier
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - L Lens
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Ljungberg
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - B Lommel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - J Louko
- Department of Physics, University of Jyväskylä, 40014 Jyväskylä, Finland
| | - C-C Meyer
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - A Mistry
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - C Mokry
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - P Papadakis
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - E Parr
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - J L Pore
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - I Ragnarsson
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - J Runke
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - M Schädel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - H Schaffner
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - B Schausten
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - D A Shaughnessy
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P Thörle-Pospiech
- Helmholtz Institute Mainz, 55099 Mainz, Germany
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - N Trautmann
- Department Chemie-Standort TRIGA, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Uusitalo
- Department of Physics, University of Jyväskylä, 40014 Jyväskylä, Finland
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6
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Haas R, Hufnagel M, Abrosimov R, Düllmann CE, Krupp D, Mokry C, Renisch D, Runke J, Scherer UW. Alpha spectrometric characterization of thin 233U sources for 229(m)Th production. RADIOCHIM ACTA 2020. [DOI: 10.1515/ract-2020-0032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Four different techniques were applied for the production of 233U alpha recoil ion sources, providing 229Th ions. They were compared with respect to a minimum energy spread of the 229Th recoil ions, using the emitted alpha particles as an indicator. The techniques of Molecular Plating, Drop-on-Demand inkjet printing, chelation from dilute nitric acid solution on chemically functionalized silicon surfaces, and self-adsorption on passivated titanium surfaces were used. All fabricated sources were characterized by using alpha spectrometry, radiographic imaging, and scanning electron microscopy. A direct validation for the estimated recoil ion rate was obtained by collecting 228Th recoil ions from 232U recoil ion sources prepared by self-adsorption and Molecular Plating. The chelation and the self-adsorption based approaches appear most promising for the preparation of recoil ion sources delivering monochromatic recoil ions.
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Affiliation(s)
- Raphael Haas
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
- Helmholtz Institute Mainz , 55099 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH , 64291 Darmstadt , Germany
- PRISMA Cluster of Excellence, Johannes Gutenberg University Mainz , 55099 Mainz , Germany
| | - Michelle Hufnagel
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
| | - Roman Abrosimov
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
| | - Christoph E. Düllmann
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
- Helmholtz Institute Mainz , 55099 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH , 64291 Darmstadt , Germany
- PRISMA Cluster of Excellence, Johannes Gutenberg University Mainz , 55099 Mainz , Germany
| | - Dominik Krupp
- Institut für Physikalische Chemie und Radiochemie, Hochschule Mannheim – University of Applied Sciences , 68163 Mannheim , Germany
| | - Christoph Mokry
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
- Helmholtz Institute Mainz , 55099 Mainz , Germany
| | - Dennis Renisch
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
- Helmholtz Institute Mainz , 55099 Mainz , Germany
| | - Jörg Runke
- Department of Chemistry - TRIGA Site , Johannes Gutenberg University Mainz , 55099 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH , 64291 Darmstadt , Germany
| | - Ulrich W. Scherer
- Institut für Physikalische Chemie und Radiochemie, Hochschule Mannheim – University of Applied Sciences , 68163 Mannheim , Germany
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7
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Sikorsky T, Geist J, Hengstler D, Kempf S, Gastaldo L, Enss C, Mokry C, Runke J, Düllmann CE, Wobrauschek P, Beeks K, Rosecker V, Sterba JH, Kazakov G, Schumm T, Fleischmann A. Measurement of the ^{229}Th Isomer Energy with a Magnetic Microcalorimeter. Phys Rev Lett 2020; 125:142503. [PMID: 33064540 DOI: 10.1103/physrevlett.125.142503] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/08/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
We present a measurement of the low-energy (0-60 keV) γ-ray spectrum produced in the α decay of ^{233}U using a dedicated cryogenic magnetic microcalorimeter. The energy resolution of ∼10 eV, together with exceptional gain linearity, allows us to determine the energy of the low-lying isomeric state in ^{229}Th using four complementary evaluation schemes. The most precise scheme determines the ^{229}Th isomer energy to be 8.10(17) eV, corresponding to 153.1(32) nm, superseding in precision previous values based on γ spectroscopy, and agreeing with a recent measurement based on internal conversion electrons. We also measure branching ratios of the relevant excited states to be b_{29}=9.3(6)% and b_{42}<0.7%.
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Affiliation(s)
- Tomas Sikorsky
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Jeschua Geist
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
| | - Daniel Hengstler
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
| | - Sebastian Kempf
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
| | - Loredana Gastaldo
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
| | - Christian Enss
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
| | - Christoph Mokry
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
- SHE Chemistry, Helmholtz Institute Mainz, Staudingerweg 18, 55128 Mainz, Germany
| | - Jörg Runke
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
- SHE Chemistry, GSI Helmholtzzentrum für Schwerionenforschung mbH, Planckstr. 1, 64291 Darmstadt, Germany
| | - Christoph E Düllmann
- Department of Chemistry - TRIGA Site, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
- SHE Chemistry, Helmholtz Institute Mainz, Staudingerweg 18, 55128 Mainz, Germany
- SHE Chemistry, GSI Helmholtzzentrum für Schwerionenforschung mbH, Planckstr. 1, 64291 Darmstadt, Germany
| | - Peter Wobrauschek
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Kjeld Beeks
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Veronika Rosecker
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Johannes H Sterba
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Georgy Kazakov
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Thorsten Schumm
- Institute for Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Vienna, Austria
| | - Andreas Fleischmann
- Kirchhoff-Institute for Physics, Heidelberg University, INF 227, 69120 Heidelberg, Germany
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8
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Kneip N, Düllmann CE, Gadelshin V, Heinke R, Mokry C, Raeder S, Runke J, Studer D, Trautmann N, Weber F, Wendt K. Highly selective two-step laser ionization schemes for the analysis of actinide mixtures. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s10751-020-01712-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
AbstractResonance ionization mass spectroscopy has proven to be a very efficient and selective method for the spatially resolved ultratrace determination of actinide contaminations, and the analysis of specific element and isotopic distributions on surfaces and environment particles. We report on the identification of highly element-selective optical excitation schemes identified for this purpose, with a particular focus on the precise determination of the isobaric ratios of 235U to 239Pu as well as 243Am to 241Pu. The chosen two-step ionization schemes were characterized with respect to their element selectivity on synthetic multi-element actinide mixtures, with an element ratio Pu : Am : U of 1 : 10 : 104, a composition which is typical, e.g., for spent nuclear reactor fuels.
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9
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Lens L, Yakushev A, Düllmann CE, Asai M, Ballof J, Block M, David HM, Despotopulos J, Di Nitto A, Eberhardt K, Even J, Götz M, Götz S, Haba H, Harkness-Brennan L, Heßberger FP, Herzberg RD, Hoffmann J, Hübner A, Jäger E, Judson D, Khuyagbaatar J, Kindler B, Komori Y, Konki J, Kratz JV, Krier J, Kurz N, Laatiaoui M, Lahiri S, Lommel B, Maiti M, Mistry AK, Mokry C, Moody K, Nagame Y, Omtvedt JP, Papadakis P, Pershina V, Runke J, Schädel M, Scharrer P, Sato T, Shaughnessy D, Schausten B, Thörle-Pospiech P, Trautmann N, Tsukada K, Uusitalo J, Ward A, Wegrzecki M, Wiehl N, Yakusheva V. Online chemical adsorption studies of Hg, Tl, and Pb on SiO2 and Au surfaces in preparation for chemical investigations on Cn, Nh, and Fl at TASCA. RADIOCHIM ACTA 2018. [DOI: 10.1515/ract-2017-2914] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Online gas-solid adsorption studies with single-atom quantities of Hg, Tl, and Pb, the lighter homologs of the superheavy elements (SHE) copernicium (Cn, Z=112), nihonium (Nh, Z=113), and flerovium (Fl, Z=114), were carried out using short-lived radioisotopes. The interaction with Au and SiO2 surfaces was studied and the overall chemical yield was determined. Suitable radioisotopes were produced in fusion-evaporation reactions, isolated in the gas-filled recoil separator TASCA, and flushed rapidly to an adjacent setup of two gas chromatography detector arrays covered with SiO2 (first array) and Au (second array). While Tl and Pb adsorbed on the SiO2 surface, Hg interacts only weakly and reached the Au-covered array. Our results contribute to elucidating the influence of relativistic effects on chemical properties of the heaviest elements by providing experimental data on these lighter homologs.
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Affiliation(s)
- Lotte Lens
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Alexander Yakushev
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Christoph Emanuel Düllmann
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Masato Asai
- Japan Atomic Energy Agency , 319-1195 Tokai-mura, Naka-gun, Ibaraki , Japan
| | - Jochen Ballof
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Section Isolde, Cern , 1211 Geneva , Switzerland
| | - Michael Block
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Helena May David
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | | | - Antonio Di Nitto
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Klaus Eberhardt
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Julia Even
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
- KVI-Center for Advanced Radiation , Technology University of Groningen , 9747 AA Groningen , The Netherlands
| | - Michael Götz
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Stefan Götz
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | | | | | - Fritz Peter Heßberger
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Rodi D. Herzberg
- Department of Physics , University of Liverpool , L69 7ZE Liverpool , UK
| | - Jan Hoffmann
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Annett Hübner
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Egon Jäger
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Daniel Judson
- Department of Physics , University of Liverpool , L69 7ZE Liverpool , UK
| | - Jadambaa Khuyagbaatar
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Birgit Kindler
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | | | - Joonas Konki
- Section Isolde, Cern , 1211 Geneva , Switzerland
- Department of Physics , University of Jyväskylä , 40014 Jyväskylä , Finland
| | - Jens Volker Kratz
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
| | - Jörg Krier
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Nikolaus Kurz
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Mustapha Laatiaoui
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Susanta Lahiri
- Chemical Sciences Division , Saha Institute of Nuclear Physics , 700064 Kolkata , India
| | - Bettina Lommel
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Moumita Maiti
- Department of Physics , Indian Institute of Technology Roorkee , 247667 Uttarakhand , India
| | - Andrew K. Mistry
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Christoph Mokry
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Ken Moody
- Lawrence Livermore National Laboratory , Livermore, CA 94551 , USA
| | - Yuichiro Nagame
- Japan Atomic Energy Agency , 319-1195 Tokai-mura, Naka-gun, Ibaraki , Japan
| | | | | | - Valeria Pershina
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Jörg Runke
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Matthias Schädel
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Japan Atomic Energy Agency , 319-1195 Tokai-mura, Naka-gun, Ibaraki , Japan
| | - Paul Scharrer
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Tetsuya Sato
- Japan Atomic Energy Agency , 319-1195 Tokai-mura, Naka-gun, Ibaraki , Japan
| | - Dawn Shaughnessy
- Lawrence Livermore National Laboratory , Livermore, CA 94551 , USA
| | - Brigitta Schausten
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
| | - Petra Thörle-Pospiech
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Norbert Trautmann
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
| | - Kazuaki Tsukada
- Japan Atomic Energy Agency , 319-1195 Tokai-mura, Naka-gun, Ibaraki , Japan
| | - Juha Uusitalo
- Department of Physics , University of Jyväskylä , 40014 Jyväskylä , Finland
| | - Andrew Ward
- Department of Physics , University of Liverpool , L69 7ZE Liverpool , UK
| | | | - Norbert Wiehl
- Institut für Kernchemie , Johannes Gutenberg-Universität , 55122 Mainz , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
| | - Vera Yakusheva
- GSI Helmholtzzentrum für Schwerionenforschung , 64291 Darmstadt , Germany
- Helmholtz-Institut Mainz , 55099 Mainz , Germany
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10
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Dorrer H, Chrysalidis K, Goodacre TD, Düllmann CE, Eberhardt K, Enss C, Gastaldo L, Haas R, Harding J, Hassel C, Johnston K, Kieck T, Köster U, Marsh B, Mokry C, Rothe S, Runke J, Schneider F, Stora T, Türler A, Wendt K. Production, isolation and characterization of radiochemically pure 163Ho samples for the ECHo-project. RADIOCHIM ACTA 2018. [DOI: 10.1515/ract-2017-2877] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Several experiments on the study of the electron neutrino mass are based on high-statistics measurements of the energy spectrum following electron capture of the radionuclide 163Ho. They rely on the availability of large, radiochemically pure samples of 163Ho. Here, we describe the production, separation, characterization, and sample production within the Electron Capture in Holmium-163 (ECHo) project. 163Ho has been produced by thermal neutron activation of enriched, prepurified 162Er targets in the high flux reactor of the Institut Laue-Langevin, Grenoble, France, in irradiations lasting up to 54 days. Irradiated targets were chemically processed by means of extraction chromatography, which allowed separating the formed Ho from the 162Er target-material and from the main byproducts 170Tm and 171Tm, which are co-produced in GBq amounts. Decontamination factors of >500 for Er and of >105 for Tm and yields of 3.6·1016 and 1.2·1018 atoms of 163Ho were obtained, corresponding to a recovery yield of 95 % of Ho in the chemical separation. The Ho-fraction was characterized by means of γ-ray spectrometry, Inductively-Coupled-Plasma Mass Spectrometry (ICP-MS), Resonance Ionization Mass Spectrometry (RIMS) and Neutron Activation Analysis (NAA). In this process, the thermal neutron capture cross section of 163Ho was measured to σHo-163 to Ho-164m= (23±3) b and σHo-163 to Ho-164g= (156±9) b for the formation of the two isomers of 164Ho. Specific samples were produced for further purification by mass separation to isolate 163Ho from the Ho-isotope mixture, as needed for obtaining the energy spectrum within ECHo. The partial efficiency for this second separation step is (32±5) %.
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Affiliation(s)
- Holger Dorrer
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
- Universität Bern , Bern , Switzerland
- Paul Scherrer Institut , Villigen , Switzerland , E-mail:
| | | | | | - Christoph E. Düllmann
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
- GSI Helmholtzzentrum für Schwerionenforschung , Darmstadt , Germany
| | | | | | | | - Raphael Haas
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
| | - Jonathan Harding
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
- Cardiff University , Cardiff , UK
| | | | | | - Tom Kieck
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
| | | | | | | | - Sebastian Rothe
- CERN , Geneva , Switzerland
- University of Manchester , Manchester , UK
| | - Jörg Runke
- GSI Helmholtzzentrum für Schwerionenforschung , Darmstadt , Germany
| | | | | | - Andreas Türler
- Universität Bern , Bern , Switzerland
- Paul Scherrer Institut , Villigen , Switzerland
| | - Klaus Wendt
- Johannes Gutenberg-Universität Mainz , Mainz , Germany
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11
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Schönberg P, Mokry C, Runke J, Schönenbach D, Stöbener N, Thörle-Pospiech P, Trautmann N, Reich T. Application of Resonance Ionization Mass Spectrometry for Ultratrace Analysis of Technetium. Anal Chem 2017; 89:9077-9082. [PMID: 28737889 DOI: 10.1021/acs.analchem.7b01778] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This work shows the ability of resonance ionization mass spectrometry (RIMS) to determine 99gTc at the ultratrace level. The characterization of the prepared samples by X-ray photoelectron spectroscopy (XPS) and optimization of the RIMS setup for this purpose, as well as the application of the RIMS method to a soil sample, are presented in this article. 97Tc was used as a tracer isotope to determine the amount of 99gTc in a soil sample with RIMS. With 8.8 × 1010 atoms of 97Tc as the tracer, the concentration of 99gTc was found to be 1.5 × 109 atoms per gram of dried sample material, demonstrating the sensitivity of the method. Furthermore, it could be shown that the 97Tc solution contained 98Tc as well. This is the first time that 97,98,99gTc have been simultaneously measured with RIMS.
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Affiliation(s)
- Pascal Schönberg
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Christoph Mokry
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Jörg Runke
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Daniela Schönenbach
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Nils Stöbener
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Petra Thörle-Pospiech
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Norbert Trautmann
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
| | - Tobias Reich
- Institute of Nuclear Chemistry, Johannes Gutenberg University , D-55099 Mainz, Germany
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12
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Khuyagbaatar J, Yakushev A, Düllmann CE, Ackermann D, Andersson LL, Asai M, Block M, Boll RA, Brand H, Cox DM, Dasgupta M, Derkx X, Di Nitto A, Eberhardt K, Even J, Evers M, Fahlander C, Forsberg U, Gates JM, Gharibyan N, Golubev P, Gregorich KE, Hamilton JH, Hartmann W, Herzberg RD, Heßberger FP, Hinde DJ, Hoffmann J, Hollinger R, Hübner A, Jäger E, Kindler B, Kratz JV, Krier J, Kurz N, Laatiaoui M, Lahiri S, Lang R, Lommel B, Maiti M, Miernik K, Minami S, Mistry A, Mokry C, Nitsche H, Omtvedt JP, Pang GK, Papadakis P, Renisch D, Roberto J, Rudolph D, Runke J, Rykaczewski KP, Sarmiento LG, Schädel M, Schausten B, Semchenkov A, Shaughnessy DA, Steinegger P, Steiner J, Tereshatov EE, Thörle-Pospiech P, Tinschert K, Torres De Heidenreich T, Trautmann N, Türler A, Uusitalo J, Ward DE, Wegrzecki M, Wiehl N, Van Cleve SM, Yakusheva V. 48Ca+249Bk fusion reaction leading to element Z = 117: long-lived α-decaying 270Db and discovery of 266Lr. Phys Rev Lett 2014; 112:172501. [PMID: 24836239 DOI: 10.1103/physrevlett.112.172501] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Indexed: 06/03/2023]
Abstract
The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-μs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."
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Affiliation(s)
- J Khuyagbaatar
- Helmholtz Institute Mainz, 55099 Mainz, Germany and GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Yakushev
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - Ch E Düllmann
- Helmholtz Institute Mainz, 55099 Mainz, Germany and GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - D Ackermann
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | | | - M Asai
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - M Block
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R A Boll
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H Brand
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - D M Cox
- University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - M Dasgupta
- The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - X Derkx
- Helmholtz Institute Mainz, 55099 Mainz, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - A Di Nitto
- Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - K Eberhardt
- Helmholtz Institute Mainz, 55099 Mainz, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Even
- Helmholtz Institute Mainz, 55099 Mainz, Germany
| | - M Evers
- The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | | | | | - J M Gates
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - N Gharibyan
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | | | - K E Gregorich
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - J H Hamilton
- Vanderbilt University, Nashville, Tennessee 37235, USA
| | - W Hartmann
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R-D Herzberg
- University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - F P Heßberger
- Helmholtz Institute Mainz, 55099 Mainz, Germany and GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - D J Hinde
- The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - J Hoffmann
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - R Hollinger
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Hübner
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - E Jäger
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - B Kindler
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - J V Kratz
- Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Krier
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Laatiaoui
- Helmholtz Institute Mainz, 55099 Mainz, Germany
| | - S Lahiri
- Saha Institute of Nuclear Physics, Kolkata 700064, India
| | - R Lang
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - B Lommel
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - M Maiti
- Saha Institute of Nuclear Physics, Kolkata 700064, India
| | - K Miernik
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S Minami
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - A Mistry
- University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - C Mokry
- Helmholtz Institute Mainz, 55099 Mainz, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - H Nitsche
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | | | - G K Pang
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - P Papadakis
- University of Liverpool, Liverpool L69 7ZE, United Kingdom and University of Jyväskylä, 40351 Jyväskylä, Finland
| | - D Renisch
- Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - J Roberto
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | | | - J Runke
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - K P Rykaczewski
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | | | - M Schädel
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany and Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - B Schausten
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | | | - D A Shaughnessy
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - P Steinegger
- Paul Scherrer Institute, 5232 Villigen, Switzerland and University of Bern, 3012 Bern, Switzerland
| | - J Steiner
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | - E E Tereshatov
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - P Thörle-Pospiech
- Helmholtz Institute Mainz, 55099 Mainz, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - K Tinschert
- GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany
| | | | - N Trautmann
- Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - A Türler
- Paul Scherrer Institute, 5232 Villigen, Switzerland and University of Bern, 3012 Bern, Switzerland
| | - J Uusitalo
- University of Jyväskylä, 40351 Jyväskylä, Finland
| | - D E Ward
- Lund University, 22100 Lund, Sweden
| | - M Wegrzecki
- Institute of Electron Technology, 02-668 Warsaw, Poland
| | - N Wiehl
- Helmholtz Institute Mainz, 55099 Mainz, Germany and Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - S M Van Cleve
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - V Yakusheva
- Helmholtz Institute Mainz, 55099 Mainz, Germany
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13
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Forsberg U, Rudolph D, Golubev P, Sarmiento L, Yakushev A, Andersson LL, Nitto AD, Düllmann C, Gates J, Gregorich K, Gross C, Heßberger F, Herzberg RD, Khuyagbaatar J, Kratz J, Rykaczewski K, Schädel M, Åberg S, Ackermann D, Block M, Brand H, Carlsson B, Cox D, Derkx X, Eberhardt K, Even J, Fahlander C, Gerl J, Jäger E, Kindler B, Krier J, Kojouharov I, Kurz N, Lommel B, Mistry A, Mokry C, Nitsche H, Omtvedt J, Papadakis P, Ragnarsson I, Runke J, Schaffner H, Schausten B, Thörle-Pospiech P, Torres T, Traut T, Trautmann N, Türler A, Ward A, Ward D, Wiehl AN. Spectroscopic Tools Applied to Element Z = 115 Decay Chains. EPJ Web of Conferences 2014. [DOI: 10.1051/epjconf/20146602036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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14
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Rudolph D, Forsberg U, Golubev P, Sarmiento LG, Yakushev A, Andersson LL, Di Nitto A, Düllmann CE, Gates JM, Gregorich KE, Gross CJ, Heßberger FP, Herzberg RD, Khuyagbaatar J, Kratz JV, Rykaczewski K, Schädel M, Åberg S, Ackermann D, Block M, Brand H, Carlsson BG, Cox D, Derkx X, Eberhardt K, Even J, Fahlander C, Gerl J, Jäger E, Kindler B, Krier J, Kojouharov I, Kurz N, Lommel B, Mistry A, Mokry C, Nitsche H, Omtvedt JP, Papadakis P, Ragnarsson I, Runke J, Schaffner H, Schausten B, Thörle-Pospiech P, Torres T, Traut T, Trautmann N, Türler A, Ward A, Ward DE, Wiehl N. Spectroscopy of element 115 decay chains. Phys Rev Lett 2013; 111:112502. [PMID: 24074079 DOI: 10.1103/physrevlett.111.112502] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Indexed: 06/02/2023]
Abstract
A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z>112. Comprehensive Monte Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.
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Mokry C. Otitis media in children. N Engl J Med 1995; 333:1151; author reply 1152. [PMID: 7565958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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