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1. Cross section measurements in the $^{12}$C+$^{12}$C system

Author

S. Della Negra, Sergio Almaraz-Calderon, Oliver S. Kirsebom, B. Bucher, C. L. Jiang, R. V. F. Janssens, Anne Meyer, Rashi Talwar, X.D. Tang, John P. Greene, B. B. Back, M. Heine, G. Fruet, X. Fang, Fairouz Hammache, D. J. Henderson, S. A. Kuvin, P. Adsley, Catherine Deibel, M. Rudigier, Kalle Auranen, S. Zhu, S. Courtin, M. Albers, D. Bourgin, M. P. Carpenter, Martín Alcorta, D. Seweryniak, Daniel Santiago-Gonzalez, D. Montanari, F. Haas, B. P. Kay, Calem Hoffman, P. H. Regan, D. G. Jenkins, P. F. Bertone, J. Sethi, C. Stodel, Claudio Ugalde, A. Lefebvre-Schuhl, J. Lesrel, A. D. Ayangeakaa, Clayton Dickerson, K. E. Rehm, B. DiGiovine, L. Morris, N. de Séréville, R. C. Pardo, Melina Avila, T. Lauritsen, S. Bottoni, S. T. Marley, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-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), 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), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 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), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, 010308 nuclear & particles physics, QC1-999, Measure (physics), Aucun, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Coincidence, law.invention, Nuclear physics, Ignition system, Cross section (physics), chemistry, 13. Climate action, law, 0103 physical sciences, Nuclear astrophysics, Nuclear fusion, 010306 general physics, Carbon
Abstract

International audience; The 12C+12C fusion reaction is one of the most important for nuclear astrophysics since it determines the carbon ignition in stellar environments. Two experiments which make use of the gamma-particle coincidence technique to measure the 12C+12C S-factors at deep sub barrier energies are discussed. Results are presented showing a decrease of the S-factor below Ec.m. = 3 MeV.

Published
2017

2. Neutron knockout from $^{68,70}$Ni ground and isomeric states

Author

C. M. Campbell, Jie Chen, F. G. Kondev, A. Korichi, C. J. Prokop, M. P. Carpenter, T. Lauritsen, M. Albers, C. J. Chiara, Shumpei Noji, Calem Hoffman, E. Lunderberg, S. Zhu, S. Suchyta, R. V. F. Janssens, C. Langer, J. S. Berryman, D. Weisshaar, H. L. Crawford, Alexandra Gade, V. M. Bader, F. Recchia, Kathrin Wimmer, D. Bazin, Sean Liddick, B. A. Brown, S. R. Stroberg, J. A. Tostevin, T.R. Baugher, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), 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, History, 010308 nuclear & particles physics, Nuclear Theory, Gamma ray, Fermi surface, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Computer Science Applications, Education, Physics and Astronomy (all), Atomic orbital, Excited state, Neutron number, 0103 physical sciences, Neutron, Atomic physics, 010306 general physics, Nuclear Experiment, Harmonic oscillator, Excitation
Abstract

International audience; Neutron-rich isotopes are an important source of new information on nuclear physics. Specifically, the spin-isospin components in the nucleon-nucleon (NN) interaction, e.g., the proton-neutron tensor force, are expected to modify shell structure in exotic nuclei. These potential changes in the intrinsic shell structure are of fundamental interest. The study of the excitation energy of states corresponding to specific configurations in even-even isotopes, together with the single-particle character of the first excited states of odd-A, neutron-rich Ni isotopes, probes the evolution of the neutron orbitals around the Fermi surface as a function of the neutron number a step forward in the understanding of the region and the nature of the NN interaction at large N/Z ratios. In an experiment carried out at the National Superconducting Cyclotron Laboratory [1], new spectroscopic information was obtained for 68Ni and the distribution of single-particle strengths in 67,69Ni was characterized by means of single-neutron knockout from 68,70Ni secondary beams. The spectroscopic strengths, deduced from the measured partial cross sections to the individual states tagged by their de-exciting gamma rays, is used to identify and quantify configurations that involve neutron excitations across the N = 40 harmonic oscillator shell closure. The de-excitation γ rays were measured with the GRETINA tracking array [2]. The results challenge the validity of the most current shell-model Hamiltonians and effective interactions, highlighting shortcomings that cannot yet be explained. These results suggest that our understanding of the low-energy states in such nuclei is not complete and requires further investigation.

Published
2017

3. Stability and synthesis of superheavy elements: Fighting the battle against fission – example of $^{254}$No

Author

Andreas Martin Heinz, S. Zhu, G. Henning, B. Gall, S. Lakshmi, A. V. Karpov, N. Rowley, M. P. Carpenter, G. Gurdal, B. P. Kay, Calem Hoffman, P. F. Bertone, A. Lopez-Martens, Martín Alcorta, D. Boilley, Paul Greenlees, D. H. Potterveld, C. J. Lister, R. V. F. Janssens, T. L. Khoo, E. A. McCutchan, C. J. Chiara, C. Nair, J. Piot, P. Reiter, A. M. Rogers, F. G. Kondev, P. Chowdhury, K. Hauschild, T. Lauristen, D. Seweryniak, M. Asai, B. B. Back, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), Normandie Université (NU), 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), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), 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), Rudolph, Dirk, 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), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Fission, QC1-999, Nuclear Theory, Shell (structure), nuclear stability, Superheavy Elements, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Stability (probability), Nuclear physics, 0103 physical sciences, medicine, Physics::Atomic and Molecular Clusters, 010306 general physics, Nuclear Experiment, Quantum, Spontaneous fission, Physics, nobelium, ta114, 010308 nuclear & particles physics, fission barrier, superheavy elements, medicine.anatomical_structure, Atomic physics, Nucleus
Abstract

International audience; Superheavy nuclei exist solely due to quantum shell effects,which create a pocket in the potential-energy surface of the nucleus, thusproviding a barrier against spontaneous fission. Determining the height ofthe fission barrier and its angular-momentum dependence is important toquantify the role that microscopic shell corrections play in enhancing andextending the limits of nuclear stability. In this talk, the first measurement ofa fission barrier in the very heavy nucleus 254No will be presented.

Published
2016

4. Shape Coexistence in 67Co, 66,68,70,72Ni, and 71Cu

Author

Noritaka Shimizu, E. Lunderberg, S. J. Williams, S. Zhu, Shumpei Noji, A. Korichi, Sean Liddick, Dominique Bazin, Takaharu Otsuka, W. B. Walters, A. M. Rogers, Yusuke Tsunoda, Michio Honma, T.R. Baugher, D. Weisshaar, N. Larson, J. L. Harker, M. Albers, Yutaka Utsuno, C. Langer, F. Recchia, C. J. Prokop, F. G. Kondev, T. Lauritsen, M. P. Carpenter, H. M. David, Martín Alcorta, Calem Hoffman, P. F. Bertone, H. L. Crawford, S. Suchyta, Alexandra Gade, D. Seweryniak, V. M. Bader, D. T. Doherty, A. O. Macchiavelli, C. J. Chiara, S. R. Stroberg, Kathrin Wimmer, R. V. F. Janssens, C. M. Campbell, Jun Chen, J. S. Berryman, Michigan State University [East Lansing], Michigan State University System, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), Jozef Stefan Inst, Univ Zagreb, Phys Dept, Ruder Boskov Inst, 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, [PHYS]Physics [physics], Work (thermodynamics), 010308 nuclear & particles physics, Monte Carlo method, SHELL model, Prolate spheroid, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Maxima and minima, Physics and Astronomy (all), 0103 physical sciences, Isotonic, Atomic physics, 010306 general physics, National laboratory
Abstract

International audience; Analyses of data from both deep inelastic reactions at Argonne National Laboratory and single-and multiple-particle knockout reactions at Michigan State University revealed new gamma-ray transitions in even-even Ni-66,68,70,72(38,40,42,44) and in Co-67(40) that provide strong evidence for multiple shape coexistence at N = 38 and 40 and deep prolate minima in Ni-70(42) and isotonic Cu-71(42). A new transition at 642 keV is proposed for Ni-66 as the prolate 2(+) to 0(+) transition. Two new transitions in Ni-72 at 915 and 1225 keV were identified in the knock-out reaction study and could represent de-population of prolate states. Taken together with recent theoretical work using the Monte Carlo shell model, a well defined region of shape coexistence can be seen existing precisely between 38

Published
2015

5. Exploring the stability of super heavy elements: First Measurement of the Fission Barrier of $^{254} $No

Author

David Boilley, J. Piot, K. Hauschild, D. H. Potterveld, T. Lauristen, T. L. Khoo, F. G. Kondev, S. Zhu, M. Asai, E. A. McCutchan, G. Henning, C. J. Chiara, C. J. Lister, P. Reiter, Andreas Martin Heinz, C. Nair, A. M. Rogers, N. Rowley, Martín Alcorta, M. P. Carpenter, B. P. Kay, A. Lopez-Martens, Calem Hoffman, G. Gurdal, P. F. Bertone, B. B. Back, P. Chowdhury, B. Gall, S. Lakshmi, A. V. Karpov, R. V. F. Janssens, D. Seweryniak, Paul Greenlees, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), CSNSM SNO, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), 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)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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 de Caen Normandie (UNICAEN), Normandie Université (NU), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), 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)-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)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-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), Lunardi, S., Bizzeti, P.G., Kabana, Sonia, Bucci, C., Chiari, M., Dainese, A., Nezza, P. Di, Menegazzo, R., Nannini, A., Signorini, C., and Valiente-Dobon, J.J.

Subjects
Physics, ta114, Fission, heavy elements, QC1-999, Nuclear Theory, fission barrier, Transactinide element, stability, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, medicine.anatomical_structure, medicine, Nuclear structure, Multiplicity (chemistry), Total energy, Atomic physics, Nuclear Experiment, Saturation (magnetic), Nucleus, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract

The gamma-ray multiplicity and total energy emitted by the heavy nucleus 254No have been measured at 2 different beam energies. From these measurements, the initial distributions of spin I and excitation energy E * of 254No were constructed. The distributions display a saturation in excitation energy, which allows a direct determination of the fission barrier. 254No is the heaviest shell-stabilized nucleus with a measured fission barrier. © Owned by the authors, published by EDP Sciences, 2014.

Published
2013

6. Configuration mixing and relative transition rates between low-spin states in Ni-68

Author

Jun Chen, H. L. Crawford, Alexandra Gade, Shumpei Noji, F. Recchia, D. T. Doherty, D. Weisshaar, E. Lunderberg, S. Zhu, D. Bazin, V. M. Bader, C. J. Chiara, T. Lauritsen, T.R. Baugher, M. Albers, N. Larson, R. V. F. Janssens, F. G. Kondev, D. Seweryniak, C. Langer, B. A. Brown, William B. Walters, J. S. Berryman, A. Korichi, H. M. David, Christopher Prokop, C. M. Campbell, Sean Liddick, S. J. Williams, Martín Alcorta, A. M. Rogers, A. O. Macchiavelli, S. Suchyta, S. R. Stroberg, Kathrin Wimmer, M. P. Carpenter, Calem Hoffman, P. F. Bertone, CSNSM SNO, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), 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)-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)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), 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, Spin states, 010308 nuclear & particles physics, Excited state, 0103 physical sciences, SHELL model, Atomic physics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010306 general physics, 01 natural sciences, Energy (signal processing), Mixing (physics)
Abstract

The low-spin level scheme of ${}^{68}$Ni was investigated following two-neutron-knockout and multinucleon-transfer reactions. The energy of the first excited state was determined to be ${E}_{x}({0}_{2}^{+})=1603.5(3)$ keV. Relative $B(E2)$ transition probabilities were deduced and compared with shell-model calculations using several modern effective interactions. Theory reproduces the data well, but indicates substantial mixing of multi-particle, multi-hole configurations for the lowest observed ${0}^{+}$ and ${2}^{+}$ states.

Published
2013

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