First <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>β</mi></math>-delayed <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>γ</mi></math>-ray spectroscopy of <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>Nb</mi><mprescripts></mprescripts><none></none><mn>109</mn></mmultiscripts></math>: Single-quasiparticle states with prolate shape in <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>Mo</mi><mprescripts></mprescripts><none></none><mn>109</mn></mmultiscripts></math>

S. Bae; T. Sumikama; P. M. Walker; J. G. Li; F. R. Xu; S. Choi; J. Ha; F. Browne; A. M. Bruce; I. Nishizuka; S. Nishimura; P. Doornenbal; G. Lorusso; P.-A. Söderström; H. Watanabe; R. Daido; Z. Patel; S. Rice; L. Sinclair; J. Wu; Z. Xu; A. Yagi; H. Baba; N. Chiga; R. Carroll; F. Didierjean; Y. Fang; N. Fukuda; G. Gey; E. Ideguchi; N. Inabe; T. Isobe; D. Kameda; I. Kojouharov; N. Kurz; T. Kubo; S. Lalkovski; Z. Li; R. Lozeva; H. Nishibata; A. Odahara; Z. Podolyák; P. H. Regan; O. J. Roberts; H. Sakurai; H. Schaffner; G. Simpson; H. Suzuki; H. Takeda; M. Tanaka; J. Taprogge; V. Werner; O. Wieland

doi:10.1103/PhysRevC.111.054317

First $β$ -delayed $γ$ -ray spectroscopy of ${}^{109}{Nb}$ : Single-quasiparticle states with prolate shape in ${}^{109}{Mo}$

S. Bae ^1,2,3,4,*, T. Sumikama^2,5,†, P. M. Walker ⁶, J. G. Li⁷, F. R. Xu ⁸, S. Choi¹, J. Ha ¹, F. Browne ^2,9, A. M. Bruce ⁹ et al.

I. Nishizuka⁵, S. Nishimura ², P. Doornenbal ², G. Lorusso^2,6,10, P.-A. Söderström ^2,11, H. Watanabe^2,12, R. Daido¹³, Z. Patel ^2,6, S. Rice^2,6, L. Sinclair^2,14, J. Wu^2,15, Z. Xu ^16,17, A. Yagi¹³, H. Baba ², N. Chiga^5,2, R. Carroll⁶, F. Didierjean ¹⁸, Y. Fang¹³, N. Fukuda², G. Gey ^19,20, E. Ideguchi ¹³, N. Inabe², T. Isobe ², D. Kameda², I. Kojouharov ²¹, N. Kurz²¹, T. Kubo ², S. Lalkovski ²², Z. Li¹⁵, R. Lozeva ^18,23, H. Nishibata¹³, A. Odahara ¹³, Z. Podolyák ⁶, P. H. Regan ^6,10, O. J. Roberts ⁹, H. Sakurai ², H. Schaffner²¹, G. Simpson¹⁹, H. Suzuki², H. Takeda², M. Tanaka^13,24, J. Taprogge ^2,25,26, V. Werner ^27,28,29, and O. Wieland ³⁰

¹Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
²RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
³Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon 34126, Republic of Korea
⁴Center for Nuclear Study, University of Tokyo, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
⁵Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan
⁶Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
⁷CAS Key Laboratory of High Precision Nuclear Spectroscopy, Institute of Modern Physics, Lanzhou 730000, China
⁸School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
⁹School of Computing, Engineering, and Mathematics, University of Brighton, Brighton BN2 4GJ, United Kingdom
¹⁰National Physical Laboratory, Teddington, Middlesex TW11 0LW, United Kingdom
¹¹Extreme Light Infrastructure-Nuclear Physics (ELI-NP)/Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Str. Reactorulu, Măgurele 077125, Romania
¹²IRCNPC, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China
¹³Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
¹⁴Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
¹⁵School of Physics, Peking University, Beijing 100871, China
¹⁶Department of Physics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
¹⁷Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong
¹⁸IPHC, CNRS/IN2P3, Université de Strasbourg, 67037 Strasbourg, France
¹⁹LPSC, Université Grenoble-Alpes, CNRS/IN2P3, F-38026 Grenoble Cedex, France
²⁰ILL, 38042 Grenoble Cedex, France
²¹GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
²²Department of Physics, University of Sofia, 1164 Sofia, Bulgaria
²³IJCLab, CNRS/IN2P3, Université Paris-Saclay, F-91405 Orsay, France
²⁴Research Center for Nuclear Physics (RCNP), Osaka University, Toyonaka, Osaka 560-0043, Japan
²⁵Departamento de Física Teórica, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
²⁶Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain
²⁷A. W. Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520, USA
²⁸Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
²⁹Helmholtz Forschungsakademie Hessen für FAIR (HFHF), D-64289 Darmstadt, Germany
³⁰INFN Sezione di Milano, I-20133 Milano, Italy

^*Contact author: shbae@cns.s.u-tokyo.ac.jp
^†Contact author: toshiyuki.sumikama@riken.jp

PDF

Phys. Rev. C 111, 054317 – Published 21 May, 2025

DOI: https://doi.org/10.1103/PhysRevC.111.054317

Abstract

The $β$ -delayed $γ$ -ray spectroscopy of ${}^{109}{Nb}$ was performed to investigate the structure of ${}^{109}{Mo}$ for the first time at the RIBF, Japan. Over one hundred transitions were assigned to ${}^{109}{Mo}$ , of these two were from the known isomeric state, and a new 33.1 keV excited state below the isomeric state was identified. The multipolarities of the transitions depopulating the isomeric state were restricted considering the internal conversion coefficients and empirically recommended upper limits of transition strengths. The intrinsic gyromagnetic ratio of the isomeric-state band was extracted, and the rotational band of the ground state was identified. The configurations of the ground and isomeric states in ${}^{109}{Mo}$ were assigned to the $ν 1 / 2^{+} [411]$ and $ν 5 / 2^{+} [413]$ orbitals, respectively, with prolate shape. From the $log f t$ analysis, the ground state in ${}^{109}{Nb}$ and a new excited state in ${}^{109}{Mo}$ with a small $log f t$ value were assigned to the $π 5 / 2^{+} [422]$ and $ν 5 / 2^{+} [402]$ orbitals, respectively. The assignments were supported by potential energy surface calculations using the configuration-constrained method with a triaxially deformed Woods-Saxon potential. Although the $ν 1 / 2^{+} [411]$ orbital was successfully predicted as the ground state, the order of quasiparticle configurations for excited states was not reproduced. The neutron emission probability in ${}^{109}{Nb}$ $β$ -decay was evaluated to be $27 (11) %$ utilizing the $β$ -delayed $γ$ rays of ${}^{109}{Tc}$ and ${}^{108}{Mo}$ .

Physical Review C

Export citation

Export citation

First $β$ -delayed $γ$ -ray spectroscopy of ${}^{109}{Nb}$ : Single-quasiparticle states with prolate shape in ${}^{109}{Mo}$

Abstract

Physics Subject Headings (PhySH)

Authorization Required

Other Options

Supplemental Material (Subscription Required)

References (Subscription Required)

Outline

Information

Filter

Filter

Article Lookup

Enter a citation

First β-delayed γ-ray spectroscopy of Nb109: Single-quasiparticle states with prolate shape in Mo109

Abstract

Physics Subject Headings (PhySH)

Authorization Required

Log in via your institution

Log in via APS Member Subscription

Other Options

Supplemental Material (Subscription Required)

References (Subscription Required)

First $β$ -delayed $γ$ -ray spectroscopy of ${}^{109}{Nb}$ : Single-quasiparticle states with prolate shape in ${}^{109}{Mo}$