Nuclear Structure Working Group

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Nuclear Structure Working Group
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General Groupings

• Proton-Rich
• D. Seweryniak (structure around 100Sn)
• CARIBU
• D. Hartley (triaxial nuclei), D. Kulp (neg.
  parity bands)
• C. Chiara (RIB 7Li), R. Janssens (g-factor
  studies)
• N. Koller (g-factor studies), R. Casten (binding
  energies)
• V. Werner (fast timing lifetime measurements)
• Heavy Elements
• W. Loveland (make them), A. Heinz (structure)
• T.L. Khoo (single-particle energies)
• High-Spin
• L. Riedinger (tetrahedral), S. Tabor (island of
  inversion)
• X. Wang (ultra high-spin)

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Experimental Needs for 100Sn

• Main emphasis on excited states in 100Sn and
  single-particle states and nucleon-nucleon
  interactions using in-beam spectroscopy
• More intense beams
• Push rates in GAMMASPHERE (x5)
• Digital GS
• Beams 100-200 pnA
• Channel selection tagging with decays (bg, bp,
  p, a)
• High granularity DSSD
• Secondary fusion-evaporation reactions
• In-flight radioactive beams
• Beams 10 pmA

Phase I should do it!
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CARIBU g-factors
An example g factors of n-rich isotopes between
Z40 and Z50. Why are some g(2) smaller than
in the stable isotopes? Use RIV on CARIBU beams
to extend and improve precision of data.
Simultaneous measurement of B(E2) and g factor
252Cf Gammasphere A.G. Smith et al. PLB 591, 55
(2004)
Behavior of neutron-rich g factors
Robert channeled A. Stuchbery Noemie wants to do
clean 138Xe
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CARIBU Interesting stuff _at_ N90

• Two regions of parabolic anomalies.
• Two regions of octupole correlations
• Possible signature?

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CARIBU Coulex Beams

• Skalski et al. find stable ? minimum
• Also see superdef
• J. Hamilton et al. C.Y. Wu et al. pushed up
  around I20
• Safe Coulex to measure Q0
• Unsafe Coulex to go beyond I20
• 100Zr for tetrahedral shape?

J. Skalski et al., NPA 617, 282 (1997)
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TAKE AWAY POINTIN ALL CASES, EBIS WILL
DRAMATICALLY HELP WITH 10x MORE BEAM!!!!
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Heavy Elements
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Wish List

• Intensity, intensity, intensity
• Long experiments
• Complicated setup ? campaigns
• Dedicated detection system ? complete
  spectroscopy
• Phase I will certainly help this group!

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High-spin

• Triaxial strongly deformed bands in N 94
  Er, Hf, Ta, Re, etc.
• Identify wobbling bands and find linking
  transitions to floating bands
• Island of inversion and intruder states in A 30
• Tetrahedral shapes in Dy U

DIGITAL GAMMASPHERE IS A MUST