future triaxial studies
DESCRIPTION
169 Ta. 175 Hf. 174 Hf. 173 Hf. 170 Hf. 171 Hf. 168 Hf. 172 Hf. 167 Lu. 165 Lu. 161 Lu. 163 Lu. 164 Lu. 168 Lu. 162 Lu. 171 Ta. 165 Ta. Future Triaxial Studies. What role does the proton Fermi Surface have in the observation of wobbling? - PowerPoint PPT PresentationTRANSCRIPT
169Re
Future Triaxial StudiesFuture Triaxial Studies• What role does the proton Fermi Surface What role does the proton Fermi Surface
have in the observation of wobbling?have in the observation of wobbling?– Search for wobbling in Search for wobbling in 169169Re (approved)Re (approved)
161Lu
175Hf174Hf173Hf170Hf171Hf
162Lu
168Hf 172Hf
163Lu164Lu165Lu 168Lu167Lu
90 92 94 96 98 100 102
171Ta167Ta
161Tm
165Ta
SD seen, but no wobbling
Wobblingobserved
163Tm
169Ta
Future Triaxial StudiesFuture Triaxial Studies
• Does the iDoes the i13/213/2 sequence in sequence in 167167Ta show Ta show evolution from evolution from = 0 = 0oo to 20 to 20oo??– High-statistics lifetime experimentHigh-statistics lifetime experiment
161Lu
175Hf174Hf173Hf170Hf171Hf
162Lu
168Hf 172Hf
163Lu164Lu165Lu 168Lu167Lu
90 92 94 96 98 100 102
171Ta167Ta
161Tm
165Ta
SD seen, but no wobbling
Wobblingobserved
163Tm
169Ta
Future Triaxial StudiesFuture Triaxial Studies• Return to heavier HfReturn to heavier Hf• Why do even-even show so many SD Why do even-even show so many SD
bands while odd-A typically only have one?bands while odd-A typically only have one?• High-statistics run to observed linking High-statistics run to observed linking
transitions in transitions in 173,174173,174HfHf
161Lu
175Hf174Hf173Hf170Hf171Hf
162Lu
168Hf 172Hf
163Lu164Lu165Lu 168Lu167Lu
90 92 94 96 98 100 102
171Ta167Ta
161Tm
165Ta
SD seen, but no wobbling
Wobblingobserved
163Tm
169Ta
3 2 3 81 1 2
Equipment, computer Equipment, computer needs…needs…
• Just need Gammasphere Just need Gammasphere
• Digital DAQ would require fewer days Digital DAQ would require fewer days to perform high-statistics to perform high-statistics experimentsexperiments
Plans with CARIBUPlans with CARIBU
Predicted Stable Triaxiality at Predicted Stable Triaxiality at High Spin in N-Rich Mo and Ru High Spin in N-Rich Mo and Ru NucleiNuclei• Skalski et al. find Skalski et al. find
stable stable γγ minimumminimum
• Also see superdefAlso see superdef
• J. Hamilton et al. & J. Hamilton et al. & C.Y. Wu et al. C.Y. Wu et al. pushed up around pushed up around I=20I=20
• Safe Coulex to Safe Coulex to measure Qmeasure Q00
• Unsafe Coulex to go Unsafe Coulex to go beyond I=20beyond I=20 J. Skalski et al., NPA 617, 282 (1997)
Equipment, computer Equipment, computer needs…needs…
• Need Gammasphere Need Gammasphere
• Chico or Super-ChicoChico or Super-Chico
Hercules Projects…Hercules Projects…
nw=1
nw=2
• Triaxial nucleus allows Triaxial nucleus allows rotation about all 3 axesrotation about all 3 axes
• Collective angular momentum Collective angular momentum vector lies off principal axis vector lies off principal axis – Precession + WobblingPrecession + Wobbling
• Amount it lies off axis Amount it lies off axis quantized into wobbling quantized into wobbling phonons (nphonons (nww))
• See a family of bands based See a family of bands based on same configuration on same configuration (different n(different nww))
• Bands are linked togetherBands are linked together– I = 1 have dominant E2 natureI = 1 have dominant E2 nature
• Bands have similar propertiesBands have similar properties– Moments of inertia, quadrupole Moments of inertia, quadrupole
moment, alignmentmoment, alignmentD.R. Jensen et al., PRL 89, 142503 (02)
Direct Evidence of Direct Evidence of Triaxiality?Triaxiality?163Lu nw=0
The Continued Pursuit of The Continued Pursuit of Stable TriaxialityStable Triaxiality• Near Future:Near Future:
– Wobbling bands in tantalum nucleiWobbling bands in tantalum nuclei
• Not-too-distant FutureNot-too-distant Future– A ~ 110 neutron-rich nuclei through CARIBU A ~ 110 neutron-rich nuclei through CARIBU
STABLETRIAXIALITY ME