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Excitation and \( \gamma\)-decay coincidence measurements at the GRAF beamline for studies of pygmy and giant dipole resonances

  • N. KobayashiEmail author
  • K. Miki
  • T. Hashimoto
  • C. Iwamoto
  • A. Tamii
  • N. Aoi
  • M. P. Carpenter
  • K. Hatanaka
  • J. Isaak
  • E. Ideguchi
  • S. Morinobu
  • S. Nakamura
  • S. Noji
Regular Article - Experimental Physics
  • 18 Downloads
Part of the following topical collections:
  1. Giant, Pygmy, Pairing Resonances and Related Topics

Abstract.

Physical studies of electric dipole excitations in atomic nuclei e.g. the structure of pygmy dipole resonances and isovector giant dipole resonances are attracting much attention recently. In this article, we describe a technical development in the coincidence measurement of the excitation processes with the Grand Raiden high-resolution magnetic spectrometer and the \( \gamma\)-decay processes by the CAGRA and SC\( \gamma\) LLA efficient \( \gamma\)-detector arrays at the Research Center for Nuclear Physics at Osaka University. Specifically, we describe how we developed a new beamline (GRAF), for \( \gamma\) detection at the target position by placing the spectrometer at an angle of \( 4.5-19.0^\circ\) and by transporting the primary beam to a well-shielded beam dump. Experimental conditions and representative data are shown for each of the two \( \gamma\)-detector arrays.

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Copyright information

© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • N. Kobayashi
    • 1
    Email author
  • K. Miki
    • 2
  • T. Hashimoto
    • 3
  • C. Iwamoto
    • 4
  • A. Tamii
    • 1
  • N. Aoi
    • 1
  • M. P. Carpenter
    • 5
  • K. Hatanaka
    • 1
  • J. Isaak
    • 6
  • E. Ideguchi
    • 1
  • S. Morinobu
    • 1
  • S. Nakamura
    • 1
  • S. Noji
    • 7
  1. 1.Research Center for Nuclear PhysicsOsaka UniversityIbaraki, OsakaJapan
  2. 2.Department of PhysicsTohoku UniversitySendai, MiyagiJapan
  3. 3.Rare Isotope Science ProjectInstitute for Basic ScienceYuseong-gu, DaejeonKorea
  4. 4.Center for Nuclear StudyUniversity of TokyoWako, SaitamaJapan
  5. 5.Physics DivisionArgonne National LaboratoryArgonneUSA
  6. 6.Institut für KernphysikTechnische Universität DarmstadtDarmstadtGermany
  7. 7.National Superconducting Cyclotron LaboratoryMichigan State UniversityEast LansingUSA

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