Identification of Excited States in the Tz=+1/2 Nucleus 75Rb: The Quest for Experimental Signatures of Collective Neutron-proton Correlations

Research output: Contribution to journalArticle

Abstract

Excited states in the T-z-1/2 nucleus Rb-75 were observed for the first time using the Ca-40(Ca-40,alpha p) reaction at 128 MeV. Identification was achieved using events detected by the Daresbury recoil separator in coincidence with gamma rays detected in the 45 element EUROGAM I Ge-detector array. Threefold events were used to build a decay scheme which consists of two rotational bands observed to I-pi=(45+/2) and I-pi=(33-/2). The positive parity band in Rb-75 behaves similarly to a negative-parity band in Kr-74 and contains a region of alignment at (h) over bar omega approximate to 0.75 MeV. These data, and those of Sr-77, be interpreted by treating protons and neutrons separately in a cranked shell model approach despite a recent suggestion for the presence of T=1 neutron-proton pairing correlations in the neighboring self-conjugate, odd-odd Rb-74 ground state band. Our study suggests that some experimental observables such as the energy levels and moments of inertia, may not be able to differentiate between different T=1 pairing phases in these T-z=1/2 nuclei.

Details

Authors
  • C. J. Gross
  • W. Satula
  • J. Alexander
  • C. Baktash
  • P. J. ColemanSmith
  • D. M. Cullen
  • R. A. Cunningham
  • J. D. Garrett
  • W. Gelletly
  • A. Harder
  • M. K. Kabadiyski
  • I. Lazarus
  • K. P. Lieb
  • H. A. Roth
  • D. G. Sarantites
  • J. A. Sheikh
  • J. Simpson
  • O. Skeppstedt
  • B. J. Varley
  • D. D. Warner
External organisations
  • External Organization - Unknown
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics
Original languageEnglish
Pages (from-to)R591-R595
JournalPhysical Review C (Nuclear Physics)
Volume56
Issue number2
Publication statusPublished - 1997
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

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