Single-particle structure in neutron-rich Sr isotopes approaching the $N=60$ shape transition

Autor: T.E. Drake, P. C. Bender, Kathrin Wimmer, A. Matta, M. Marchetto, A. B. Garnsworthy, C. E. Svensson, Friedhelm Ames, G. Hackman, Aaron Chester, T. Bruhn, P. Voss, S. S. Bhattacharjee, R. Krücken, A. Knapton, David Miller, K. Kuhn, C. Unsworth, C. Aa. Diget, S. Cruz, N. A. Orr, A. Cheeseman, D. S. Cross, R. Kanungo, Jens Lassen, R. A. E. Austin, Corina Andreoiu, M. Moukaddam, C.S. Bancroft, N. Sachmpazidi, Alisher Sanetullaev, W. Korten, R. Braid, N. Terpstra, Robert Laxdal, W. N. Catford
Přispěvatelé: Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Science and Technology Facilities Council (UK), National Science Foundation (US), Natural Sciences and Engineering Research Council of Canada, British Columbia Knowledge Development Fund, Ministerio de Economía y Competitividad (España)
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Physical Review C
Physical Review C, American Physical Society, 2020, 102 (2), pp.024335. ⟨10.1103/PhysRevC.102.024335⟩
Phys.Rev.C
Phys.Rev.C, 2020, 102 (2), pp.024335. ⟨10.1103/PhysRevC.102.024335⟩
Digital.CSIC. Repositorio Institucional del CSIC
instname
ISSN: 2469-9985
2469-9993
Popis: 12 pags., 16 figs., 2 tabs.
Background: Neutron-rich nuclei around neutron number N=60 show a dramatic shape transition from spherical ground states to prolate deformation in Sr98 and heavier nuclei. Purpose: The purpose of this study is to investigate the single-particle structure approaching the shape transitional region. Method: The level structures of neutron-rich Sr93,94,95 were studied via the H2(Sr94,95,96,t) one-neutron stripping reactions at TRIUMF using a beam energy of 5.5 AMeV. γ-rays emitted from excited states and recoiling charged particles were detected by using the TIGRESS and SHARC arrays, respectively. States were identified by gating on the excitation energy and, if possible, the coincident γ radiation.Results: Triton angular distributions for the reactions populating states in ejectile nuclei Sr93,94,95 were compared with distorted wave Born approximation calculations to assign and revise spin and parity quantum numbers and extract spectroscopic factors. The results were compared with shell-model calculations and the reverse (d,p) reactions and good agreement was obtained. Conclusions: The results for the H2(Sr94,t)Sr93 and H2(Sr95,t)Sr94 reactions are in good agreement with shell-model calculations. A two-level mixing analysis for the 0+ states in Sr94 suggest strong mixing of two shapes. For the H2(Sr96,t)Sr95 reaction the agreement with the shell-model is less good. The configuration of the ground state of Sr96 is already more complex than predicted, and therefore indications for the shape transition can already be observed before N=60.
We acknowledge support from the Science and Technologies Facility Council (UK, Grants No. EP/D060575/1 and No. ST/L005727/1), the National Science Foundation (US, Grant No. PHY-1306297), the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation and the British Columbia Knowledge and Development Fund. TRIUMF receives federal funding via a contribution through the National Research Council Canada. K.W. acknowledges the support from the Spanish Ministerio de Economía, Industria y Competitividad, Gobierno de España RYC-2017-22007.
Databáze: OpenAIRE
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