Future Triaxial Studies

1
Future Triaxial Studies

• What role does the proton Fermi Surface have in
  the observation of wobbling?
• Search for wobbling in 169Re (approved)

167Ta
90
92
94
96
98
100
102
SD seen, but no wobbling
161Tm
Wobbling observed
163Tm
2
Future Triaxial Studies

• Does the i13/2 sequence in 167Ta show evolution
  from ? 0o to 20o?
• High-statistics lifetime experiment

167Ta
90
92
94
96
98
100
102
SD seen, but no wobbling
161Tm
Wobbling observed
163Tm
3
Future Triaxial Studies

• Return to heavier Hf
• Why do even-even show so many SD bands while
  odd-A typically only have one?
• High-statistics run to observed linking
  transitions in 173,174Hf

167Ta
3
2
3
8
1
1
2
90
92
94
96
98
100
102
SD seen, but no wobbling
161Tm
Wobbling observed
163Tm
4
Equipment, computer needs

• Just need Gammasphere
• Digital DAQ would require fewer days to perform
  high-statistics experiments

5
Plans with CARIBU
6
Predicted Stable Triaxiality at High Spin in
N-Rich Mo and Ru Nuclei

• 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

J. Skalski et al., NPA 617, 282 (1997)
7
Equipment, computer needs

• Need Gammasphere
• Chico or Super-Chico

8
Hercules Projects
9
Direct Evidence of Triaxiality?
nw0
nw1
163Lu

• Triaxial nucleus allows rotation about all 3 axes
• Collective angular momentum vector lies off
  principal axis
• Precession Wobbling
• Amount it lies off axis quantized into wobbling
  phonons (nw)
• See a family of bands based on same configuration
  (different nw)
• Bands are linked together
• ?I 1 have dominant E2 nature
• Bands have similar properties
• Moments of inertia, quadrupole moment, alignment

nw2
D.R. Jensen et al., PRL 89, 142503 (02)
10
The Continued Pursuit of Stable Triaxiality

• Near Future
• Wobbling bands in tantalum nuclei
• Not-too-distant Future
• A 110 neutron-rich nuclei through CARIBU

STABLE TRIAXIALITY
ME