Emerging Nuclear Collectivity: Coulomb Excitation of 106Cd

ORAL

Abstract

Nuclear collectivity has traditionally been thought to evolve through stages of seniority, vibrational, and rotational character as one moves from closed to open-shell regions of the nuclear chart. While there are several robust examples of seniority and rotational character, isolating vibrational character has been more difficult, particularly due to the transitional nature between the extremes. The Cd isotopes (Z=48) were long thought of as textbook examples of vibrational nuclei where the low-lying excitation patterns are consistent with such an interpretation. However, this narrative has since been challenged with the ever growing body of nucleon-transfer and electromagnetic matrix element data, showing major discrepancies with the vibrational model. Alternative views now include everything from weakly deformed anharmonic vibrations with double shape coexistence to weakly deformed triaxial rotations with multi shape coexistence. Results from multi-step Coulomb excitation data of 106Cd on 208Pb will be presented and compared to recent interpretations and measurements, including anomalous DSAM-based lifetime values. Excitation of the low-lying states, including two excited 0+ states, was observed in the present study. We report the first measurement of B(E2; 2_1+ -> 0_2+) and B(E2; 2_1+ -> 0_3+), a crucial piece of data for determining the nature of the weak collectivity exhibited in the Cd isotopes. In addition, electric quadrupole moments will be presented for several of the low-lying states. The E2 matrix elements allow the Kumar-Cline sum rules to be applied, giving a model independent measure of deformation on a state-by-state basis. The experiment was performed at the ATLAS facility of Argonne National Laboratory using GRETINA-CHICO2.

*This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics.

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Presenters

  • Timothy Gray

    • Oak Ridge National Laboratory

Authors

  • Timothy Gray

    • Oak Ridge National Laboratory

  • James Allmond

    • Physics Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory

  • Robert V Janssens

    • University of North Carolina at Chapel Hill
    • Department of Physics & Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC-27599-3255, USA and Triangle Universities Nuclear Laboratory, Duke University,
    • University of North Carolina Chapel Hill

  • Wolfram Korten

    • IRFU/SPhN

  • David C Radford

    • Oak Ridge National Lab

  • Akaa D Ayangeakaa

    • University of North Carolina at Chapel Hill
    • University of North Carolina at Chapel H

  • Jon C Batchelder

    • University of California, Berkeley

  • Cornelius Beausang

    • University of Richmond

  • Brian M Bucher

    • Idaho National Laboratory

  • Matthew Q Buckner

    • Lawrence Livermore Natl Lab

  • Christopher M Campbell

    • Lawrence Berkeley National Laboratory

  • Michael P Carpenter

    • Argonne National Laboratory
    • ANL

  • Douglas Cline

    • University of Rochester

  • Heather L Crawford

    • Lawrence Berkeley National Laboratory

  • H David

    • Argonne National Laboratory

  • Daniel Doherty

    • IRFU/SPhN

  • Paul Fallon

    • Lawrence Berkeley National Laboratory

  • Alfredo Galindo-Uribarri

    • Oak Ridge National Lab

  • Andreas Gorgen

    • University of Oslo

  • Carl J Gross

    • Oak Ridge National Lab

  • Katarzyna Hadynska-Klek

    • University of Oslo

  • Malin Klintefjord

    • University of Oslo

  • Kay Kolos

    • Lawrence Livermore Natl Lab
    • LLNL
    • Lawrence Livermore National Laboratory

  • M Komorowska

    • University of Warsaw

  • Filip G Kondev

    • Argonne National Laboratory
    • Physics Division, Argonne National Laboratory, Lemont, IL-60439

  • Gregory J Lane

    • Australian National University

  • Torben Lauritsen

    • Argonne National Laboratory
    • ANL

  • Augusto O Macchiavelli

    • Lawrence Berkeley National Laboratory

  • Pavel Napiorkowsi

    • University of Warsaw

  • Elizabeth Padilla-Rodal

    • Univ Nacl Autonoma de Mexico

  • L Prochniak

    • University of Warsaw

  • Walter Reviol

    • Argonne National Laboratory
    • ANL

  • Demetrios G Sarantites

    • Washington University, St. Louis

  • Julian Srebrny

    • University of Warsaw

  • Andrew E Stuchbery

    • Australian Natl Univ

  • Robert L Varner

    • Oak Ridge National Lab

  • Alexander J Wiens

    • Massachusetts Institute of Technology MIT

  • Ching-Yen Wu

    • Lawrence Livermore Natl Lab
    • LLNL

  • Chang-Hong Yu

    • Oak Ridge National Lab

  • John L Wood

    • Georgia Institute of Technology

  • K Wrzosek-Lipska

    • University of Warsaw

  • Shaofei Zhu

    • Brookhaven National Laboratory
    • Brookhaven National Lab
    • Argonne National Laboratory

  • Magda Zielinska

    • IRFU/SPhN

  • Simone Bottoni

    • Argonne National Laboratory

  • Steven D Pain

    • Oak Ridge National Laboratory
    • Oak Ridge National Lab
    • ORNL

  • Michael T Febbraro

    • Oak Ridge National Laboratory
    • Oak Ridge National Lab