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1. Monte Carlo modelling for the in vivo lung monitoring of enriched uranium: Results of an international comparison

Author

Telma Cristina Ferreira Fonseca, J.-A. Cruzate, Erick Cardenas-Mendez, D. Leone, Tomas Vrba, S. Gossio, L. Liu, Carla Oliveira, Gary H. Kramer, Jad Farah, Kevin Capello, C. Simões, Gianfranco Gualdrini, J. Bento, Uwe Reichelt, C. Li, B. Heide, M. Caldeira, L. C. Freire, A. Kyrieleis, David Broggio, J. Li, D. Sommer, M. A. Lopez, Filip Vanhavere, L.-C. Mihailescu, J. Huikari, Osamu Kurihara, D. Franck, M. Moraleda, J. F. Navarro, C. Konvalinka, M. Takahashi, N. Puerta, Pedro Teles, A. L. Lebacq, B. Perez, J.M. Gómez-Ros, J. G. Hunt, P. Cowan, Sakae Kinase, Laboratoire d'évaluation de la dose interne (DRPH/SDI/LEDI), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Instituto Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa (IST), Centre d'Etude de l'Energie Nucléaire (SCK-CEN), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Department of Engineering Physics [Beijing], Tsinghua University [Beijing] (THU), Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), Autoridad Regulatoria Nuclear (ARN), Escola Superior de Tecnologia da Saude de Lisboa, Radiation and Nuclear Safety Authority [Helsinki] (STUK), Instituto de Radioproteção e Dosimetria, Japan Atomic Energy Agency, Faculty of Nuclear Sciences and Physical Engineering [Prague] (FJFI CTU), Czech Technical University in Prague (CTU), and Agenzia Nazionale per le nuove Tecnologie, l’energia e lo sviluppo economico sostenibile (ENEA)

Subjects
medicine.medical_specialty, [SDV]Life Sciences [q-bio], Nuclear engineering, Monte Carlo method, In-vivo measurement, Voxel phantoms, Monte carlo computation, Enriched uranium, Imaging phantom, 030218 nuclear medicine & medical imaging, Counting system, 03 medical and health sciences, 0302 clinical medicine, In-vivo, MC simulation, MONTE CARLO, Calibration, medicine, Numerical calibration, Internal dosimetry, Medical physics, Instrumentation, International comparison, Intercomparisons, Radiation, Monte Carlo modelling, Counting efficiency, Monte Carlo methods, Computer simulation, 030220 oncology & carcinogenesis, Uranium, Environmental science, Experiments
Abstract

In order to assess the reliability of Monte Carlo (MC)-based numerical calibration of in vivo counting systems the EURADOS network supported a comparison of MC simulation of well-defined experiments. This action also provided training for the use of voxel phantoms. In vivo measurements of enriched uranium in a thoracic phantom have been carried out and the needed information to simulate these measurements was distributed to 17 participants. About half of the participants managed to simulate the measured counting efficiency without support from the organisers. Following additional support all participants managed to simulate the counting efficiencies within a typical agreement of ±5% with experiment. © 2012 Elsevier Ltd. All rights reserved.

Published
2012
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2. Comparison of the air-kerma x-ray standards of the NRPA, the STUK, the SSM and the LNE-LNHB in the ISO 4037 narrow spectrum series in the range 40 kV to 300 kV (EURAMET.RI(I)-S3.2)

Author

H Bjerke, J Plagnard, PO Hetland, A Kosunen, L Persson, JM Bordy, and J Huikari

Subjects
Range (particle radiation), Kerma, Materials science, Series (mathematics), General Engineering, Analytical chemistry, X-ray, Narrow spectrum
Abstract

A supplementary comparison has been made between the air-kerma standards of the NRPA (Norway), the STUK (Finland) the SSM (Sweden) and the LNE-LNHB (France) in the ISO 4037 narrow spectrum series in the range 40 kV to 300 kV. The technical protocol was approved by the CCRI(I) in April 2016. The results show the standards to be in agreement at the level of the standard uncertainty of 12, 14 and 8 parts in 10³ for the NRPA, the STUK and the SSM respectively. The results are analysed and presented in terms of degrees of equivalence. KEY WORDS FOR SEARCH Supplementary comparison, air kerma, narrow spectrum series, radiation dosimetry Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Published
2018
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3. Excitation functions for proton-induced reactions on natural hafnium: Production of 177Lu for medical use

Author

S.-J. Heselius, Teemu Siiskonen, J. Bergman, T. Lönnroth, Jan-Olof Lill, V.-P. Vartti, J. Huikari, T. Haavisto, and K. Peräjärvi

Subjects
Nuclear physics, Excitation function, Nuclear reaction, Nuclear and High Energy Physics, Radionuclide, Proton, Chemistry, chemistry.chemical_element, Nuclide, Mass spectrometry, Instrumentation, Excitation, Hafnium
Abstract

There is an increasing interest in using radioisotopes of rare earth elements for internal radiotherapy and for imaging in nuclear medicine. 177Lu is one of the promising radionuclides. This article reports on the first measurements of the excitation function for the production of 177Lu with proton-beam energies up to 17 MeV on natural hafnium targets. The experimental cross sections for the reaction natHf(p,x)177Lu were obtained by the activation of a stacked-foil target and subsequent gamma spectrometry. Theoretical cross sections were calculated up to 35 MeV with the EMPIRE nuclear reaction model code. The measured and calculated cross sections were used for deriving the thick-target yields and for estimating the production of other nuclides than 177Lu. Measured production cross sections of 175,176,177,178Ta on the same target are also presented.

Published
2009
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4. Charged particle transport and extraction studies in the NSCL gas cell for stopping radioactive fragments

Author

Ryan Ringle, D. A. Davies, David J. Morrissey, Joshua J. Savory, Peter Schury, C. Bachelet, G. K. Pang, T. Sun, J. Huikari, Stefan Schwarz, M. Facina, Chandana Sumithrarachchi, Georg Bollen, Charles M. Folden, E. Kwan, Michael Block, A. Prinke, and C. Guénaut

Subjects
Nuclear and High Energy Physics, Ion beam, Projectile, Chemistry, Ion gun, Charged particle, Ion, Nuclear physics, Ion beam deposition, Ion trap, Atomic physics, Nuclear Experiment, Instrumentation, Beam (structure)
Abstract

The NSCL gas-stopping station thermalizes high-energy projectile fragments for study in the low energy beam and ion trap (LEBIT) facility. The stopping and extraction of fast beams has been studied extensively and the extracted short-lived ions have been used in a series of mass measurements of exotic nuclei. Particle-in-cell simulations of ion drift in the gas cell have been performed. In the present paper calculation results are presented and compared to experimental data obtained with neutron-deficient and neutron-rich As and Se isotopes recently measured at LEBIT. Good agreement between the theoretical and experimental extraction efficiency was found.

Published
2008
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5. Penning trap mass measurements of rare isotopes produced by projectile fragmentation with LEBIT at NSCL

Author

Michael Block, C. Bachelet, D. A. Davies, G. K. Pang, A. Prinke, A. Kwiatowski, M. Facina, Ryan Ringle, C. Guénaut, J. Huikari, Stefan Schwarz, Joshua J. Savory, David J. Morrissey, Charles M. Folden, Peter Schury, Georg Bollen, E. Kwan, Chandana Sumithrarachchi, and T. Sun

Subjects
Physics, Spectrometer, Isotope, General Physics and Astronomy, Penning trap, Mass spectrometry, Ion, Nuclear physics, Fragmentation (mass spectrometry), Physics::Accelerator Physics, General Materials Science, Neutron, Ion trap, Physical and Theoretical Chemistry, Atomic physics, Nuclear Experiment
Abstract

The Low-Energy Beam and Ion Trap facility LEBIT at the NSCL at MSU has demonstrated that rare isotopes produced by fast-beam fragmentation can be slowed down and prepared for precision experiments with low-energy beams. High-pressure gas-stopping was combined with advanced ion manipulation techniques to carry out these studies with a high-precision 9.4-Tesla Penning trap mass spectrometer. The spectrometer has been used for a series of high precision mass measurements of short-lived neutron- and proton-rich isotopes during the past year. This paper presents an overview of the LEBIT facility and summarizes the first mass measurement results. The mass measurements of 81Se, where ground and isomeric states have been resolved, and of 80As will be discussed in detail.

Published
2007
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6. EURADOS 241Am skull measurement intercomparison

Author

A. L. Lebacq, B. Pérez-López, A. L. Shutt, Sergei Y. Tolmachev, J. Scott, D. Franck, J. Huikari, M. A. Lopez, B. Breustedt, Jakub Ośko, W. Buchholz, Barry M. Hauck, Timothy P. Lynch, Karin Fantinova, David Broggio, Chunsheng Li, I. Malatova, Kevin Capello, Tomas Vrba, P. Fojtík, D. Leone, O. Marzocchi, George Etherington, T. Pliszczyński, Pedro Alves Nogueira, J.F. Navarro-Amaro, W. Rühm, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), National Center for Nuclear Research (NCBJ), Washington State University (WSU), Helmholtz-Zentrum München (HZM), Czech Technical University in Prague (CTU), Federal Office for Radiation Protection (BfS), Radiation and Nuclear Safety Authority [Helsinki] (STUK), Karlsruhe Institute of Technology (KIT), Centre d'Etude de l'Energie Nucléaire (SCK-CEN), and 02NUK015BU.S. Department of Energy, USDOE AU-13, DE-HS0000073

Subjects
Radiation, business.industry, [SDV]Life Sciences [q-bio], Imaging phantom, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, Skull, 0302 clinical medicine, medicine.anatomical_structure, 030220 oncology & carcinogenesis, medicine, Calibration, Environmental science, Skull bone, Nuclear medicine, business, Instrumentation
Abstract

International audience; In 2011 a measurement intercomparison was launched by EURADOS WG7, with the objective of providing the participants with the tools to calibrate their detection systems for detection of 241Am in the skull bone, and evaluate the variability due to the used of the different calibration phantoms. Three skull phantoms were used in this intercomparison the USTUR Case 0102 skull phantom, the BfS skull phantom and the CSR skull phantom. Very good agreement was found between the results of the twelve participating laboratories, with relative deviations of less than 15% for the BfS phantom and less than 17% for the USTUR phantom when measurement efficiency in defined positions was compared. However, the phantoms' measured absolute 241Am activities showed discrepancies of up to a factor of 3.4. This is mainly due to the physical differences between the standard calibration phantoms used by the participants and those used in this intercomparison exercise. © 2015 Elsevier Ltd. All rights reserved.

Published
2015
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7. The LEBIT facility at MSU

Author

M. Facina, A. A. Kwiatkowski, E. Kwan, D. A. Davies, C. Bachelet, C. Guénaut, David J. Morrissey, Stefan Schwarz, Joshua J. Savory, Ryan Ringle, Michael Block, A. Prinke, G. K. Pang, Peter Schury, Charles M. Folden, Georg Bollen, J. Huikari, Chandana Sumithrarachchi, and T. Sun

Subjects
Nuclear and High Energy Physics, Spectrometer, Isotope, Chemistry, Condensed Matter Physics, Penning trap, Mass spectrometry, Atomic and Molecular Physics, and Optics, Ion, Nuclear physics, Fragmentation (mass spectrometry), Physics::Atomic Physics, Ion trap, Physical and Theoretical Chemistry, Atomic physics, Nuclear Experiment, Hybrid mass spectrometer
Abstract

The low-energy beam and ion trap facility LEBIT at the NSCL at MSU has demonstrated that rare isotopes produced by fast-beam fragmentation can be slowed down and prepared such that precision experiments with low-energy beams are possible. For this purpose high-pressure gas-stopping is employed combined with advanced ion manipulation techniques. Penning trap mass measurements on short-lived rare isotopes have been performed with a 9.4 T Penning trap mass spectrometer. Examples include 66As, which has a half-live of only 96 ms, and the super-allowed Fermi-emitter 38Ca, for which a mass accuracy of 8 ppb (280 eV) has been achieved. The high accuracy of this new mass value makes 38Ca a new candidate for the test of the conserved vector current hypothesis.

Published
2006
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8. Precision mass measurements with LEBIT at MSU

Author

Ryan Ringle, Peter Schury, D. A. Davies, David J. Morrissey, Stefan Schwarz, E. Kwan, J. Huikari, Georg Bollen, Joshua J. Savory, A. Prinke, T. Sun, and Chandana Sumithrarachchi

Subjects
Isotope, Chemistry, Isotopes of krypton, Condensed Matter Physics, Mass spectrometry, Penning trap, Ion, Nuclear physics, Fragmentation (mass spectrometry), Physics::Atomic Physics, Ion trap, Nuclide, Physical and Theoretical Chemistry, Atomic physics, Nuclear Experiment, Instrumentation, Spectroscopy
Abstract

The low-energy beam and ion trap facility (LEBIT), has been designed to facilitate a variety of experiments at low energies with rare isotopes produced by fast-beam fragmentation. Gas stopping of the fast-fragment beams and modern ion manipulation techniques are used. The first experiments to be performed are high-precision mass measurements possible with a 9.4 T Penning trap mass spectrometer. LEBIT has been recently commissioned and first experiments on stable and unstable nuclides have been performed. Here we present the results of mass measurements on stable krypton isotopes, measured with a precision of better than δ m / m = 5 × 1 0 − 8 that reveal significant deviations from the literature values for Kr 83 and Kr 84 . The paper also provides an overview of LEBIT and the first Penning trap mass measurements performed on unstable isotopes from fast-beam fragmentation.

Published
2006
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9. Production of 234,235Np and 236Pu in bombardment of 236U with protons in the energy range from 17 to 40 MeV

Author

V. S. Kolhinen, Kerttuli Helariutta, V. A. Jakovlev, S. Rinta-Antila, J. Aaltonen, J. Huikari, Wladyslaw Henryk Trzaska, and E. A. Gromova

Subjects
Excitation function, Range (particle radiation), Chemistry, Neptunium, Cyclotron, Radiochemistry, chemistry.chemical_element, Uranium, law.invention, law, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Yield (chemistry), Nuclide, Physical and Theoretical Chemistry, Atomic physics
Abstract

The production of 235Np and 236Pu by the reactions 236U(p,2n) 235Np and 236U(p,nβ−) 236Pu using the K-130 cyclotron of the University of Jyväskylä was investigated. The cross sections for the reactions were determined. Thick-target yield curves were derived based on the cross sections. The results are discussed and compared with previous data on other reactions leading to the formation of the same end products. The thick-target yield of 235Np in the 236U(p,2n) reaction is about 50 percent higher than the yield obtained in the 238U(p,4n) reaction leading to this nuclide at comparable particle energies. The purity of 236Pu produced in the 236U(p,nβ−) reaction is more than ten times better than for earlier known as the purest reaction 237Np(p,2n+pnβ−) 236Pu.

Published
2005
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10. Excitation functions of proton-induced reactions in natCu in the energy range 7–17MeV

Author

Teemu Siiskonen, J. Bergman, Jan-Olof Lill, T. Lönnroth, T. Haavisto, J. Huikari, S.-J. Heselius, and Kari Peräjärvi

Subjects
Range (particle radiation), Radiation, Proton, Isotope, Chemistry, Analytical chemistry, chemistry.chemical_element, Dose-Response Relationship, Radiation, Radiation Dosage, Copper, Energy Transfer, Models, Chemical, Isotopes of zinc, Computer Simulation, Zinc Isotopes, Gamma spectroscopy, Atomic physics, Excitation, Beam (structure)
Abstract

Elemental production cross sections were measured for (p, x ) reactions on natural Cu targets, leading to the formation of 62,63,65 Zn. These reactions are generally used for monitoring the proton beam intensity and energy e.g. in isotope production facilities. Cross sections were obtained by activation of stacked foils and subsequent gamma spectroscopy. The production data for 62,63,65 Zn between 7 and 16.5 MeV proton energy are presented as well as comparisons with literature values. Good agreement with the evaluated values was found for most of the cross-section values.

Published
2009
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11. Direct and β-delayed multi-proton emission from atomic nuclei with a time projection chamber: the cases of $^{43}$Cr, $^{45} $Fe, and $^{51}$Ni

Author

J. Pibernat, J. Giovinazzo, I. Matea, L. Perrot, S. Grévy, J. L. Pedroza, F. de Oliveira Santos, S. Leblanc, L. Audirac, J. Huikari, B. Blank, P. Ascher, L. Serani, L. Hay, C. Borcea, C. Stodel, B. A. Brown, J. C. Thomas, G. Canchel, C. Dossat, C. E. Demonchy, Noyaux exotiques (NEX), 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), RAEN, INSTRU, Grand Accélérateur National d'Ions Lourds (GANIL), 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), Institut de Physique Nucléaire d'Orsay (IPNO), 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), ELEC, 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), 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), and 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)

Subjects
Physics, Nuclear and High Energy Physics, Time projection chamber, Proton, 010308 nuclear & particles physics, Hadron, Theoretical models, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, 0103 physical sciences, Atomic nucleus, Physics::Accelerator Physics, Nuclear fusion, Atomic physics, Proton emission, Nuclear Experiment, 010306 general physics, Energy (signal processing)
Abstract

Expérience GANIL/LISE3; The two-proton radioactivity of 45Fe was studied experimentally with a time projection chamber. The aim of the experiment was the reconstruction of the proton tracks in three dimensions. Energy and angular correlations have been determined and the data are compared with theoretical models, in particular with a three-body model. Moreover, the decay of 43Cr was studied and β-delayed one-, two- and threeproton emission could be established. The correlations observed for β-delayed two-proton emission favour a sequential emission. Finally, β-delayed two-proton emission was observed for the first time for 51Ni.

Published
2012
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12. Two-Proton Radioactivity as a Tool for Nuclear Structure

Author

S. Leblanc, F. de Oliveira Santos, I. Matea, T. Kurtukian-Nieto, L. Perrot, B. Blank, Carole Dossat, G. Canchel, L. V. Grigorenko, P. Ascher, I. Companis, L. Serani, F. Delalee, L. Audirac, C. Borcea, C. Stodel, Praveen C. Srivastava, J. Huikari, S. Grévy, J. Pibernat, J. C. Thomas, B. A. Brown, C. E. Demonchy, N. Adimi, J. L. Pedroza, L. Hay, J. Giovinazzo, 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), MECA, 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), INSTRU, ELEC, Grand Accélérateur National d'Ions Lourds (GANIL), 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), H. Otsu, T. Motobayashi, P. Roussel-Chomaz, T. Otsuka, 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)-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), 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)

Subjects
Materials science, Time projection chamber, Proton, Radiochemistry, Nuclear structure, two-proton radioactivity, time-projection chamber, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS, Exotic nuclei
Abstract

International audience

Published
2011
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13. β-delayed emission of protons at the proton drip-line: the cases of [sup 43]Cr and [sup 51]Ni

Author

L. Audirac, N. Adimi, P. Ascher, B. Blank, C. Borcea, G. Canchel, C. E. Demonchy, I. Companis, F. Delalee, F. de Oliveira Santos, C. Dossat, J. Giovinazzo, S. Grévy, L. Hay, J. Huikari, T. Kurtukian-Nieto, S. Leblanc, I. Matea, J.-L. Pedroza, L. Perrot, J. Pibernat, L. Serani, C. Stodel, P. Strivatava, J.-C. Thomas, Bertram Blank, 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, B. Blank, 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)-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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Time projection chamber, Proton, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, 020206 networking & telecommunications, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear physics, 23.40.-s, 23.50.+z, 27.40.+z, 29.40.Cs, 29.40.Gx, beta-delayed emission of protons, Ionization, Time Projection Chamber, 0202 electrical engineering, electronic engineering, information engineering, Physics::Accelerator Physics, 020201 artificial intelligence & image processing, Atomic physics, Nuclear Experiment, Exotic nuclei, Line (formation)
Abstract

International audience; Studies of -delayed emission of protons for 43Cr and 51Ni were performed with a Time Projection Chamber. This detection setup allows to reconstruct in the three-dimensional space the tracks of the protons emitted. For the first time, -delayed emission of two protons is directly observed for 43Cr and 51Ni. The question about correlations between protons can be accessed. Finally, we show that 43Cr can emit up to three delayed protons.

Published
2011
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14. Experimental studies of an exotic decay mode at the proton drip‐line: the two‐proton radioactivity

Author

L. Audirac, N. Adimi, P. Ascher, B. Blank, B. A. Brown, C. Borcea, G. Canchel, I. Companis, F. Delalee, C. E. Demonchy, F. de Oliveira Santos, C. Dossat, J. Giovinazzo, S. Grévy, L. V. Grigorenko, L. Hay, J. Huikari, T. Kurtukian-Nieto, S. Leblanc, I. Matea, J.-L. Pedroza, L. Perrot, J. Pibernat, L. Serani, C. Stodel, P. Strivastava, J.-C. Thomas, Paraskevi Demetriou, Rauno Julin, Sotirios Harissopulos, 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), 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), P. Demetriou, R. Julin, S. Harissopulos, 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)-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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Time projection chamber, Isotope, Proton, Nuclear Theory, Hadron, 020206 networking & telecommunications, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Beta decay, Particle detector, Nuclear physics, 0202 electrical engineering, electronic engineering, information engineering, Physics::Accelerator Physics, 020201 artificial intelligence & image processing, Atomic physics, Nuclear Experiment, Nucleon, Radioactive decay
Abstract

Two‐proton radioactivity is an exotic decay mode for very proton‐rich nuclei. It was observed experimentally for the first time in 2002 for the nucleus 45Fe but the two protons could not be directly detected. So a new detector has been developed, a Time Projection Chamber, to individually observe the two protons emitted. It was used successfully during two experiments for the study of 45Fe and 54Zn. Energy correlations have been studied and the relative angle between the two protons is calculated.

Published
2010
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15. A time projection chamber for the three-dimensional reconstruction of two-proton radioactivity events

Author

J. Giovinazzo, R. De Oliveira, P. Hellmuth, J. L. Pedroza, J. C. Thomas, I. Matea, S. List, C. Borcea, G. Canchel, L. Hay, P. Ascher, L. Serani, C. E. Demonchy, S. Leblanc, J. Huikari, C. Dossat, B. Blank, C. Marchand, A. Rebii, L. Audirac, F. Delalee, J. Pibernat, 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), National Institute for Physics and Nuclear Engineering (NIPNE), National Institute for Physics and Nuclear Engineering, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), 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), European Organization for Nuclear Research (CERN), Grand Accélérateur National d'Ions Lourds (GANIL), 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 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)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and 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)

Subjects
Physics, Nuclear and High Energy Physics, Time projection chamber, Proton, 010308 nuclear & particles physics, Nuclear Theory, Context (language use), Two-proton radioactivity, 01 natural sciences, Nuclear physics, 0103 physical sciences, 29.40.Cs, 29.30.Ep, 29.90.+r, Physics::Accelerator Physics, ASIC electronics, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Nuclear Experiment, 010306 general physics, Instrumentation
Abstract

Publication commune avec MECA, INSTRU et ELEC (CENBG), Expérience GANIL LISE2000 et LISE-D6 : E457a; Two-proton radioactivity was observed in 2002 in the decay of 45Fe. However, the experiments performed at that time did not allow the observation of the two protons directly. We present here a new setup based on the principle of a time-projection chamber that enabled us for the first time to identify directly the two protons. The new setup permits the observation and reconstruction in three dimensions of the traces of the protons and to determine thus their individual energies and their relative angle. We will discuss the setup in all necessary details and describe its performances in the context of two-proton radioactivity and β-delayed two-proton emission studies.

Published
2010
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17. Beta-delayed gamma and proton spectroscopy near the Z = N line

Author

A. Kankainen, S. A. Eliseev, T. Eronen, S. P. Fox, U. Hager, J. Hakala, W. Huang, J. Huikari, D. Jenkins, A. Jokinen, S. Kopecky, I. Moore, A. Nieminen, Yu. N. Novikov, H. Penttilä, A. V. Popov, S. Rinta-Antila, H. Schatz, D. M. Seliverstov, G. K. Vorobjev, Y. Wang, and J. Äystö

Published
2009
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18. Performance of IGISOL 3

Author

H. Penttilä, J. Billowes, P. Campbell, P. Dendooven, V. -V. Elomaa, T. Eronen, U. Hager, J. Hakala, J. Huikari, A. Jokinen, A. Kankainen, P. Karvonen, S. Kopecky, B. Marsh, I. Moore, A. Nieminen, A. Popov, S. Rinta-Antila, Y. Wang, and J. Äystö

Published
2009
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19. Precise half-life measurement of the Si-26 ground state

Author

A. Jokinen, Antti Saastamoinen, J. L. Pedroza, P. Delahaye, J. Ronkainen, Tommi Eronen, J. Huikari, T. Sonoda, J. Giovinazzo, Juho Rissanen, S. Rahaman, I. Matea, J. Souin, Christine Weber, I. D. Moore, Ulrike Hager, J. Hakala, Bertram Blank, Viki-Veikko Elomaa, J. Äystö, and Anu Kankainen

Subjects
Physics, Nuclear and High Energy Physics, Branching fraction, 010308 nuclear & particles physics, FOS: Physical sciences, Half-life, 01 natural sciences, Nuclear physics, 0103 physical sciences, Relative precision, Nuclear Experiment (nucl-ex), 010306 general physics, Ground state, Nuclear Experiment, Nuclear Physics
Abstract

The beta-decay half-life of 26Si was measured with a relative precision of 1.4*10e3. The measurement yields a value of 2.2283(27) s which is in good agreement with previous measurements but has a precision that is better by a factor of 4. In the same experiment, we have also measured the non-analogue branching ratios and could determine the super-allowed one with a precision similar to the previously reported measurements. The experiment was done at the Accelerator Laboratory of the University of Jyvaskyla where we used the IGISOL technique with the JYFLTRAP facility to separate pure samples of 26Si., Comment: 8 pages, 7 figures; accepted by EPJA

Published
2008

20. Studies with Exotic Nuclei: Two Proton Radioactivity

Author

C. Borcea, B. Blank, G. Canchel, C. E. Demonchy, J. Giovinazzo, L. Hay, J. Huikari, S. Leblanc, I. Matea, J.-L. Pedroza, J. Pibernat, L. Serani, F. de Oliveira Santos, S. Grevy, L. Perrot, C. Stodel, J.-C. Thomas, C. Dossat, Livius Trache, Sabin Stoica, 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Livius Trache, Sabin Stoica, 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), 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)

Subjects
Physics, Proton, Isotope, Physics::Instrumentation and Detectors, Hadron, Nuclear shell model, 020206 networking & telecommunications, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Particle detector, Baryon, Nuclear physics, nuclei with mass number 39 to 58, nuclear shell model, time projection chambers, 0202 electrical engineering, electronic engineering, information engineering, High Energy Physics::Experiment, 020201 artificial intelligence & image processing, Atomic physics, Nuclear Experiment, Nucleon, 23.50.+z, 21.10.-k, 27.40.+z, 21.60.Cs, Radioactive decay, proton emission decay
Abstract

Commune avec INSTRU et ELEC; International audience; In the present paper, we present measurements that led to the discovery of two-proton radioactivity. After the first observation of this decay mode for 45Fe, new measurements evidenced this decay mode also for 54Zn and most likely 48Ni. A new detector based on the time-projection chamber principle allowed now to visualize the two protons directly.

Published
2008
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21. First Direct Observation of Two Protons in the Decay ofFe45with a Time-Projection Chamber

Author

J. Huikari, J. Giovinazzo, C. E. Demonchy, F. de Oliveira Santos, L. Hay, C. Stodel, S. Leblanc, C. Borcea, S. Grévy, G. Canchel, J. L. Pedroza, L. Perrot, J. Pibernat, L. Serani, J.-C. Dalouzy, B. Blank, J. C. Thomas, I. Matea, and Carole Dossat

Subjects
Physics, Work (thermodynamics), Time projection chamber, 010308 nuclear & particles physics, Nuclear Theory, Direct observation, General Physics and Astronomy, Half-life, 01 natural sciences, Decay energy, Double beta decay, 0103 physical sciences, Physics::Accelerator Physics, Atomic physics, Nuclear Experiment, 010306 general physics, Ground state, Common emitter
Abstract

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

Published
2007
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22. A time projection chamber to study two-proton radioactivity

Author

J. Huikari, J. L. Pedroza, L. Perrot, C. E. Demonchy, F. de Oliveira Santos, J. Giovinazzo, P. Hellmuth, A. Rebii, G. Canchel, R. De Oliveira, L. Audirac, B. Blank, S. Leblanc, C. Borcea, Carole Dossat, C. Stodel, S. Grévy, C. Marchand, J. C. Thomas, I. Matea, F. Delalee, L. Serani, J. Pibernat, L. Hay, S. List, Institut de Physique Nucléaire d'Orsay (IPNO), 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), M. Lion, W. Mittig, O. Navilliat-Cuncic, P. Roussel-Chomaz, A.C.C. Villari, 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), and 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)

Subjects
Physics, Nuclear and High Energy Physics, Time projection chamber, Proton, 010308 nuclear & particles physics, Two-proton radioactivity, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, 0103 physical sciences, 29.40.Cs, 29.30.Ep, 29.90.+r, Physics::Accelerator Physics, ASIC electronics, Nuclear Experiment, 010306 general physics, Instrumentation
Abstract

Commune avec MECA, INSTRU et ELEC; International audience; Two-proton radioactivity was observed in two experiments in 2002 in the decay of 45Fe. However, these experiments did not allow the observation of the two protons directly. In the present paper, we present a new setup based on the principle of a time projection chamber which enabled us for the first time to identify directly the two protons. The new setup permits the observation and reconstruction in three dimensions of the traces of the protons. We will discuss the setup and describe its performances.

Published
2007
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23. Observation of individual particles in the two-proton radioactivity with a time projection chamber

Author

J. Giovinazzo, B. Blank, L. Audirac, C. Borcea, G. Canchel, C. E. Demonchy, F. de Oliveira Santos, C. Dossat, S. Grévy, L. Hay, J. Huikari, S. Leblanc, I. Matea, J.-L. Pedroza, L. Perrot, J. Pibernat, L. Serani, C. Stodel, J.-C. Thomas, Lídia S. Ferreira, Paramasivan Arumugan, 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), Grand Accélérateur National d'Ions Lourds (GANIL), 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), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), 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)

Subjects
Physics, Time projection chamber, Proton, Nuclear Theory, Nuclear structure, 020206 networking & telecommunications, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, Angular correlation, 0202 electrical engineering, electronic engineering, information engineering, Physics::Accelerator Physics, Particle, 020201 artificial intelligence & image processing, Atomic physics, Nuclear Experiment, Projectile fragmentation, Energy (signal processing)
Abstract

Commune avec INSTRU et ELEC; International audience; Two decay modes were predicted for nuclei at the proton drip-line by Goldanskii[ in the early 60's: the 1-proton radioactivity for odd-Z nuclei and the 2-proton radioactivity for even-Z nuclei. The first one was discovered experimentally in the 80's, while the 2-proton decay was observedfor the first time in 2002 in the decay of 45Fe at GANIL and GSI. This was confirmed by a recent GANIL experiment, that also stated 54Zn as a precursor of this decay model. This new radioactivity may provide many experimental pieces of information about masses for nuclei beyond the drip-line, single particle levels sequence, tunnelling processes or the pairing interaction. The challenging goal for experimental two-proton studies is then to perform a more extensive analysis of the decay process by measuring energy and angular correlations between the two emitted particles. This should allow for a comparison with models taking into account the structure of involved nuclei and the decay mechanism. For this purpose, a Time Projection Chamber detector has been developed at CENBG. It has been used successfully in an experiment performed at GANIL in September 2006, leading to the first direct observation of individual protons emitted in the decay of 45Fe. The experimental set-up and the first results of this experiment will be presented.

Published
2007
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24. High-precision Penning trap mass measurements ofCa37,38and their contributions to conserved vector current and isobaric mass multiplet equation

Author

G. Bollen, M. Facina, Ryan Ringle, Chandana Sumithrarachchi, Peter Schury, E. Kwan, T. Sun, Joshua J. Savory, J. Huikari, D. A. Davies, A. Prinke, D. J. Morrissey, and Stefan Schwarz

Subjects
Physics, Nuclear and High Energy Physics, Mass excess, law, Cyclotron, Ion trap, Atomic physics, Penning trap, Mass spectrometry, Multiplet, Excitation, law.invention, Ion
Abstract

Penning trap mass measurements of the super-allowed \ensuremath{\beta} emitter $^{38}\mathrm{Ca}$ and of $^{37}\mathrm{Ca}$ have been performed using the low-energy beam and ion trap facility at the coupled cyclotron facility of the National Superconducting Cyclotron Laboratory. Both isotopes were produced by fast-beam fragmentation and in-flight separation. The mass of $^{38}\mathrm{Ca}$ (${T}_{1/2}=440$ ms) was determined with a precision of $\ensuremath{\delta}m=280$ eV, corresponding to a relative mass uncertainty of $\ensuremath{\delta}m/m\ensuremath{\approx}8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$. A mass excess value of ME $=\ensuremath{-}22508.52(28)$ was obtained. $^{38}\mathrm{Ca}$ is a ${0}^{+}\ensuremath{\rightarrow}{0}^{+}$ emitter, and the improved mass value makes it a new candidate for testing the conserved vector current hypothesis. For $^{37}\mathrm{Ca}$ (${T}_{1/2}=180$ ms), a mass excess value of ME $=\ensuremath{-}13135.7(1.4)$ was measured. Using the quadratic form of the isobaric mass multiplet equation and the improved $^{37}\mathrm{Ca}$ mass value, a precise prediction of the excitation energy of the $^{37}\mathrm{Ar}$ isobaric analog state was obtained.

Published
2007
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25. First direct observation of two protons in the decay of 45Fe with a time-projection chamber

Author

J, Giovinazzo, B, Blank, C, Borcea, G, Canchel, J-C, Dalouzy, C E, Demonchy, F, de Oliveira Santos, C, Dossat, S, Grévy, L, Hay, J, Huikari, S, Leblanc, I, Matea, J-L, Pedroza, L, Perrot, J, Pibernat, L, Serani, C, Stodel, and J-C, Thomas

Abstract

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

Published
2007

27. The LEBIT facility at MSU

Author

S. Schwarz, C. Bachelet, M. Block, G. Bollen, D. Davies, M. Facina, C. M. Folden, C. Guénaut, E. Kwan, A. A. Kwiatkowski, D. J. Morrissey, G. Pang, A. Prinke, R. Ringle, J. Savory, P. Schury, C. Sumithrarachchi, T. Sun, and J. Huikari

Published
2007
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28. Laser Ion Source Project at IGISOL

Author

A. Nieminen, I. D. Moore, J. Billowes, P. Campbell, K. T. Flanagan, Ch. Geppert, J. Huikari, A. Jokinen, T. Kessler, B. Marsh, H. Penttilä, S. Rinta-Antila, B. Tordoff, K. D. A. Wendt, and J. Äystö

Published
2006
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29. Experiments with Thermalized Rare Isotope Beams from Projectile Fragmentation: A Precision Mass Measurement of the SuperallowedβEmitterCa38

Author

Georg Bollen, Joshua J. Savory, Ryan Ringle, M. Facina, Chandana Sumithrarachchi, A. Prinke, L. Weissman, D. A. Davies, Stefan Schwarz, P. A. Lofy, E. Kwan, Peter Schury, T. Sun, D. J. Morrissey, and J. Huikari

Subjects
Nuclear reaction, Physics, Nuclear physics, Spectrometer, General Physics and Astronomy, Nuclide, Ion trap, Atomic physics, Nuclear Experiment, Penning trap, Mass spectrometry, Charged particle, Radioactive decay
Abstract

The mass of the short-lived radio nuclide {sup 38}Ca (T{sub 1/2}=440 ms) has been measured with the 9.4-T Penning trap mass spectrometer of the Low-Energy Beam and Ion Trap Facility. A mass uncertainty of {delta}m=280 eV has been achieved, corresponding to {delta}m/m=8x10{sup -9}. The result makes {sup 38}Ca, a superallowed beta emitter, a new candidate to test the conserved-vector-current hypothesis. The experiment is also the first demonstration that short-lived radioactive isotopes produced by projectile fragmentation of relativistic heavy-ion beams can be slowed down and prepared such that precision experiments of this kind are possible.

Published
2006
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30. Experiments with thermalized rare isotope beams from projectile fragmentation: a precision mass measurement of the superallowed beta emitter 38Ca

Author

G, Bollen, D, Davies, M, Facina, J, Huikari, E, Kwan, P A, Lofy, D J, Morrissey, A, Prinke, R, Ringle, J, Savory, P, Schury, S, Schwarz, C, Sumithrarachchi, T, Sun, and L, Weissman

Abstract

The mass of the short-lived radio nuclide 38Ca (T(1/2) = 440 ms) has been measured with the 9.4-T Penning trap mass spectrometer of the Low-Energy Beam and Ion Trap Facility. A mass uncertainty of deltam = 280 eV has been achieved, corresponding to deltam/m = 8 x 10(-9). The result makes 38Ca, a superallowed beta emitter, a new candidate to test the conserved-vector-current hypothesis. The experiment is also the first demonstration that short-lived radioactive isotopes produced by projectile fragmentation of relativistic heavy-ion beams can be slowed down and prepared such that precision experiments of this kind are possible.

Published
2006

31. A Systematic Study of β− Decay of Neutron-Rich Rh and Ag Isotopes

Author

J. C. Wang, J. Huikari, S. Nummela, J. Äysto, K. Perjärvi, P.G. Dendooven, J. Szerypo, S. Rinta-Antila, A. Nieminen, V. S. Kolhinen, Y. Wang, A. Jokinen, G. Lhersonnaeu, and H. Penttilä

Subjects
Nuclear physics, Decay scheme, Isotope, Proton, Fission, Chemistry, Gamma spectroscopy, Neutron, Nuclear Experiment, Spectroscopy, Beta decay
Abstract

Beta decay of neutron‐rich even‐mass 114–118Rh and 116–120Ag isotopes has been studied using on‐line mass‐separated sources that were produced by applying 25 MeV proton induced symmetric fission of natural uranium at the IGISOL facility. The β‐γ and γ‐γ coincidence spectroscopy is employed in all cases that enables for the construction of the decay scheme and for the deduction of the decay properties. Systematics for two‐quasineutron states in 114,116,118Pd and for three‐phonon multiplet in 114,116,118Cd are presented and discussed.

Published
2006
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32. TRAPS FOR FISSION PRODUCT IONS AT IGISOL

Author

J. Szerypo, S. Rinta-Antila, Ulrike Hager, T. Eronen, A. Jokinen, H. Penttilä, J. Huikari, V. S. Kolhinen, S. Kopecky, J. Hakala, A. Nieminen, and J. Äysto

Subjects
Nuclear fission product, Materials science, Radiochemistry, Fission product yield, Ion
Published
2004
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34. Clarification of the three-body decay of 12C (12.71 MeV)

Author

H O U, Fynbo, Y, Prezado, U C, Bergmann, M J G, Borge, P, Dendooven, W X, Huang, J, Huikari, H, Jeppesen, P, Jones, B, Jonson, M, Meister, G, Nyman, K, Riisager, O, Tengblad, I S, Vogelius, Y, Wang, L, Weissman, K, Wilhelmsen Rolander, and J, Aystö

Abstract

Using beta decays of a clean source of 12N produced at the IGISOL facility, we have measured the breakup of the 12C (12.71 MeV) state into three alpha particles with a segmented particle detector setup. The high quality of the data permits solving the question of the breakup mechanism of the 12.71 MeV state, a longstanding problem in few-body nuclear physics. Among existing models, a modified sequential model fits the data best, but systematic deviations indicate that a three-body description is needed.

Published
2003

35. Ion beam cooler-buncher at the IGISOL facility

Author

J. Huikari, R. Moore, Paul Campbell, G. Tungate, J. Hakala, Iain Moore, H.L. Thayer, S. Rinta-Antila, A. Nieminen, J. Billowes, J. Äystö, V. S. Kolhinen, J. Szerypo, A. Jokinen, and D. H. Forest

Subjects
Radioactive ion beams, Materials science, Bunches, Ion beam, Physics::Plasma Physics, Physics::Accelerator Physics, Physics::Atomic Physics, Atomic physics, Nuclear Experiment, Penning trap, Spectroscopy, Ion
Abstract

An ion beam cooler-buncher for manipulating low-energy radioactive ion beams at the IGISOL facility is described. The cooler-buncher serves as a source of cooled ion bunches for collinear laser spectroscopy and it will be used for preparation of ion bunches for injection into a Penning trap system.

Published
2003
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38. Self-diffusion of (31)Si and (71)Ge in relaxed Si(0.20)Ge(0.80) layers

Author

P, Laitinen, A, Strohm, J, Huikari, A, Nieminen, T, Voss, C, Grodon, I, Riihimäki, M, Kummer, J, Aystö, P, Dendooven, J, Räisänen, and W, Frank

Abstract

Self-diffusion of implanted (31)Si and (71)Ge in relaxed Si(0.20)Ge(0.80) layers has been studied in the temperature range 730-950 degrees C by means of a modified radiotracer technique. The temperature dependences of the diffusion coefficients were found to be Arrhenius-type with activation enthalpies of 3.6 eV and 3.5 eV and preexponential factors of 7.5 x 10(-3) m(2) s(-1) and 8.1 x 10(-3) m(2) s(-1) for (31)Si and (71)Ge , respectively. These results suggest that, as in Ge, in Si(0.20)Ge(0.80) both (31)Si and (71)Ge diffuse via a vacancy mechanism. Since in Si(0.20)Ge(0.80) (71)Ge diffuses only slightly faster than (31)Si , in self-diffusion studies on Si-Ge (71)Ge radioisotopes may be used as substitutes for the "uncomfortably" short-lived (31)Si radiotracer atoms.

Published
2002

39. The fission ion guide: Present performance and future development

Author

Peter Dendooven, J. Äystö, A. Jokinen, A. Nieminen, V. S. Kolhinen, S. Hankonen, J. C. Wang, A. Honkanen, Markku Oinonen, J. Huikari, K. Peräjärvi, G. Lhersonneau, H. Penttilä, and M. Huhta

Subjects
Fission products, Ion beam, Isotope, Fission, Chemistry, Nuclear Theory, Particle accelerator, law.invention, Ion, Nuclear physics, law, Physics::Accelerator Physics, Ion trap, Nuclear Experiment, Beam (structure)
Abstract

Presently, the Jyvaskyla IGISOL facility delivers mass-separated beams of fission products with an intensity of 2700 ions/s per mb cross section. A further increase in yield is expected from the ongoing investigations into improving the design and understanding better the behavior of the fission ion guide. The study of new neutron-rich nuclei is hindered by the presence of different kinds of contaminants in the mass-separated beam: isobaric isotopes, isotopes of neighboring masses and doubly-charged ions. These problems will be solved by producing isotopically pure beams. We are developing an ion beam cooler+ion trap combination for this purpose.

Published
1998
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40. Cooling, bunching and isobar separation of radioactive ion beams at IGISOL

Author

V. S. Kolhinen, K. Peräjärvi, A. Nieminen, J. Äystö, P.G. Dendooven, A. Jokinen, and J. Huikari

Subjects
Ion beam, Chemistry, Particle accelerator, Mass spectrometry, Ion gun, law.invention, Ion, Isotope separation, Nuclear physics, law, Physics::Accelerator Physics, Thermal emittance, Physics::Atomic Physics, Beam emittance, Atomic physics
Abstract

Universality of the ion guide technique allows the mass separation of isotopes of any element. However, this feature also means unselectivity in respect to chemical element number and results in severe isobaric background. Also the operation of the ion guide with the maximum yield increases the energy spread and the emittance of the ion beam. To overcome these problems, new means to cool, bunch and mass purify the ion beam will be developed. The weak radioactive ion beam will be cooled in a gas-filled radiofrequency quadrupole and further mass purified and bunched in a Penning-trap.

Published
1998
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42. Nuclear charge radii and electromagnetic moments of radioactive scandium isotopes and isomers.

Author

M Avgoulea, Yu P Gangrsky, K P Marinova, S G Zemlyanoi, S Fritzsche, D Iablonskyi, C Barbieri, E C Simpson, P D Stevenson, J Billowes, P Campbell, B Cheal, B Tordoff, M L Bissell, D H Forest, M D Gardner, G Tungate, J Huikari, A Nieminen, and H Penttila

Subjects
NUCLEAR charge, SCANDIUM isotopes, RADIOISOTOPES, NUCLEAR isomers, LASER spectroscopy, MAGNETIC dipoles, QUADRUPOLE moments, HYPERFINE structure
Abstract

Collinear laser spectroscopy experiments with the Sc+ transition 3d4s 3D2 - 3d4p 3F3 at l = 363.1 nm were performed on the 42-46Sc isotopic chain using an ion guide isotope separator with a cooler-buncher. Nuclear magnetic dipole and electric quadrupole moments as well as isotope shifts were determined from the hyperfine structure for five ground states and two isomers. Extensive multi-configurational Dirac-Fock calculations were performed in order to evaluate the specific mass-shift, MSMS, and field-shift, F, parameters which allowed evaluation of the charge radii trend of the Sc isotopic sequence. The charge radii obtained show systematics more like the Ti radii, which increase towards the neutron shell closure N = 20, than the symmetric parabolic curve for Ca. The changes in mean-square charge radii of the isomeric states relative to the ground states for 44Sc and 45Sc were also extracted. The charge radii difference between the ground and isomeric states of 45Sc is in agreement with the deformation effect estimated from the B(E2) measurements but is smaller than the deformation extracted from the spectroscopic quadrupole moments. [ABSTRACT FROM AUTHOR]

Published
2011
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43. The 1+→0+ Gamow–Teller strength of the 58Cug.s.→58Nig.s. transition

Author

Peter Dendooven, Juha Äystö, J. C. Wang, M. Górska, Heikki Penttilä, Veli Kolhinen, E. Roeckl, G. Lhersonneau, A. Nieminen, S. Nummela, M. La Commara, Jussi Huikari, Ari Jokinen, Kari Perajarvi, K., Peräjärvi, P., Dendooven, M., Górska, J., Huikari, A., Jokinen, V. S., Kolhinen, LA COMMARA, Marco, G., Lhersonneau, A., Nieminen, S., Nummela, H., Penttilä, E., Roeckl, J. C., Wang, and J., Äystö

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Atomic physics, Beta decay, Mass separation
Abstract

The ground-state branch in the beta decay of Cu-58 has been remeasured by using gamma-ray detection combined with ion-guide-based on-line mass separation. The measured value 80.8(7)% is three times more precise and in agreement with the earlier reported value. The deduced Gamow-Teller strength of this transition, to be used for the calibration of the charge-exchange reactions, is 0.0821(7). (C) 2001 Elsevier Science B.V. All rights reserved.

Published
2001
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44. NEUTRON FIELD CHARACTERISTICS AT RADIATION METROLOGY LABORATORY OF STUK.

Author

Huikari J, Siiskonen T, Kosunen A, and Pousi P

Subjects
Computer Simulation, Monte Carlo Method, Radiation Dosage, Americium analysis, Beryllium analysis, Californium analysis, Laboratories standards, Neutrons, Radiation Monitoring instrumentation, Radiation Monitoring methods
Abstract

Radiation metrology laboratory at Radiation and Nuclear Safety Authority (STUK) is Finnish national laboratory for ionizing radiation. In order to establish personal dose equivalent available for neutron calibration service, a project was started to evaluate the neutron reference fields in the present facility. The irradiation room conditions were characterized in order to establish reference conditions for personal dose equivalent. To verify the validity of the calculations, ambient dose equivalent rates and room return were measured and calculated for 241AmBe and 252Cf sources. First results of Monte Carlo calculations and measurements are presented in this article.

Published
2018
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45. Occupational exposure to 131I-a case study.

Author

Muikku M, Huikari J, Korpela H, Lindholm C, Paile W, and Parviainen T

Subjects
Autoradiography, Chromosome Aberrations, Female, Humans, Radiation Dosage, Radiation Monitoring, Skin radiation effects, Thyroid Gland radiation effects, Iodine Radioisotopes adverse effects, Occupational Exposure
Abstract

In a laboratory in a company manufacturing radiopharmaceuticals, a laboratory technician was contaminated with I. The employee was preparing I capsules for thyroid carcinoma treatment. The employee was wearing two pairs of protective gloves and, when changing gloves, noticed a rupture in the right inner glove but no visible rupture in the outer glove. Only 3-4 h later, routine monitoring revealed heavy contamination of the back of the right hand. Immediate actions to decontaminate the hand were taken on-site. Stable iodine was not administered. On the next day, besides persisting heavy contamination of the hand, I was also detected in the thyroid gland. Based on original measurements on-site and later follow-up at STUK, including surface contamination measurements and whole body counting, the original I activity on the hand was estimated at 12 MBq and the superficial skin dose at 33 Gy, affecting a skin area of about 10 cm. The thyroid dose was estimated at 430 mGy. Eleven days after the incident, the skin was dry and slightly desquamated. After 15 d, the skin was intact with no desquamation left. No further signs of skin damage have occurred. Cytogenetic analysis of circulating lymphocytes indicated a slight elevation of chromosomal aberrations.

Published
2014
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46. Excitation functions of proton-induced reactions in (nat)Cu in the energy range 7-17 MeV.

Author

Siiskonen T, Huikari J, Haavisto T, Bergman J, Heselius SJ, Lill JO, Lönnroth T, and Peräjärvi K

Subjects
Computer Simulation, Dose-Response Relationship, Radiation, Energy Transfer, Radiation Dosage, Copper chemistry, Copper radiation effects, Models, Chemical, Zinc Isotopes chemistry, Zinc Isotopes radiation effects
Abstract

Elemental production cross sections were measured for (p,x) reactions on natural Cu targets, leading to the formation of (62,63,65)Zn. These reactions are generally used for monitoring the proton beam intensity and energy e.g. in isotope production facilities. Cross sections were obtained by activation of stacked foils and subsequent gamma spectroscopy. The production data for (62,63,65)Zn between 7 and 16.5 MeV proton energy are presented as well as comparisons with literature values. Good agreement with the evaluated values was found for most of the cross-section values.

Published
2009
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47. First direct observation of two protons in the decay of 45Fe with a time-projection chamber.

Author

Giovinazzo J, Blank B, Borcea C, Canchel G, Dalouzy JC, Demonchy CE, de Oliveira Santos F, Dossat C, Grévy S, Hay L, Huikari J, Leblanc S, Matea I, Pedroza JL, Perrot L, Pibernat J, Serani L, Stodel C, and Thomas JC

Abstract

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

Published
2007
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48. Experiments with thermalized rare isotope beams from projectile fragmentation: a precision mass measurement of the superallowed beta emitter 38Ca.

Author

Bollen G, Davies D, Facina M, Huikari J, Kwan E, Lofy PA, Morrissey DJ, Prinke A, Ringle R, Savory J, Schury P, Schwarz S, Sumithrarachchi C, Sun T, and Weissman L

Abstract

The mass of the short-lived radio nuclide 38Ca (T(1/2) = 440 ms) has been measured with the 9.4-T Penning trap mass spectrometer of the Low-Energy Beam and Ion Trap Facility. A mass uncertainty of deltam = 280 eV has been achieved, corresponding to deltam/m = 8 x 10(-9). The result makes 38Ca, a superallowed beta emitter, a new candidate to test the conserved-vector-current hypothesis. The experiment is also the first demonstration that short-lived radioactive isotopes produced by projectile fragmentation of relativistic heavy-ion beams can be slowed down and prepared such that precision experiments of this kind are possible.

Published
2006
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49. Revised rates for the stellar triple-alpha process from measurement of 12C nuclear resonances.

Author

Fynbo HO, Diget CA, Bergmann UC, Borge MJ, Cederkäll J, Dendooven P, Fraile LM, Franchoo S, Fedosseev VN, Fulton BR, Huang W, Huikari J, Jeppesen HB, Jokinen AS, Jones P, Jonson B, Köster U, Langanke K, Meister M, Nilsson T, Nyman G, Prezado Y, Riisager K, Rinta-Antila S, Tengblad O, Turrion M, Wang Y, Weissman L, Wilhelmsen K, and Aystö J

Abstract

In the centres of stars where the temperature is high enough, three alpha-particles (helium nuclei) are able to combine to form 12C because of a resonant reaction leading to a nuclear excited state. (Stars with masses greater than approximately 0.5 times that of the Sun will at some point in their lives have a central temperature high enough for this reaction to proceed.) Although the reaction rate is of critical significance for determining elemental abundances in the Universe, and for determining the size of the iron core of a star just before it goes supernova, it has hitherto been insufficiently determined. Here we report a measurement of the inverse process, where a 12C nucleus decays to three alpha-particles. We find a dominant resonance at an energy of approximately 11 MeV, but do not confirm the presence of a resonance at 9.1 MeV (ref. 3). We show that interference between two resonances has important effects on our measured spectrum. Using these data, we calculate the triple-alpha rate for temperatures from 10(7) K to 10(10) K and find significant deviations from the standard rates. Our rate below approximately 5 x 10(7) K is higher than the previous standard, implying that the critical amounts of carbon that catalysed hydrogen burning in the first stars are produced twice as fast as previously believed. At temperatures above 10(9) K, our rate is much less, which modifies predicted nucleosynthesis in supernovae.

Published
2005
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50. Clarification of the three-body decay of 12C (12.71 MeV).

Author

Fynbo HO, Prezado Y, Bergmann UC, Borge MJ, Dendooven P, Huang WX, Huikari J, Jeppesen H, Jones P, Jonson B, Meister M, Nyman G, Riisager K, Tengblad O, Vogelius IS, Wang Y, Weissman L, Wilhelmsen Rolander K, and Aystö J

Abstract

Using beta decays of a clean source of 12N produced at the IGISOL facility, we have measured the breakup of the 12C (12.71 MeV) state into three alpha particles with a segmented particle detector setup. The high quality of the data permits solving the question of the breakup mechanism of the 12.71 MeV state, a longstanding problem in few-body nuclear physics. Among existing models, a modified sequential model fits the data best, but systematic deviations indicate that a three-body description is needed.

Published
2003
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