1. High spin physics- achievements and perspectives
S. Frauendorf
IRP, Research Center
Dresden-Rossendorf, Germany
and
Department of Physics
University of Notre Dame, USA

2. The frontiers fission 1)Path to fission I 3)Isospin multiplets
6)The future
p-dripline
5) Weak symmetry breaking
A=130
SHE A
2) Triaxiality
4) Bands and isomers
around A=250
N-Z
n-dripline
Terra incognita

3. 1)Path to fission New shells: TSD Triaxial Strongly deformed
Symmetries decide: irregularbandsspin-parity sequence

4. Disappearance and recurrence of rotational bands
Courtesy M. Riley

5. Courtesy M. Riley
E.Paul et al. PRL 98, (2007)

6. First evidence for hyperdeformation?

7. wobblers
the Z=70,71 N=94,97 gaps
Courtesy M. Riley

8. p-h excitation
Why are they
different? no
wobbling
wobbling

9. 2) Triaxiality

10. Spectroscopy of fragments From spontaneous Cf fission
X.Y. Luo et al., PLB, in review
I. Stefanescu et al., NPA, in press

11. p=-
chiral
p=+
wobbler

12. Consequence of chirality: Two identical rotational bands.

13. Best case of chirality so far: chiral vibrations in
S. Zhu et al.
Phys. Rev. Lett. 91, (2003) 15

14. Chiral vibrations in 135-Nd TAC+RPA calculations
Mukhopadhyay, Almehed et al.
PRL 99, (2007)
Phonon is mainly orientation fluctuations
Same inband transition rates - Good agreement with experiment 16

15. 135-Nd Transition rates
in-band
cross band 17

16. 3)Isospin multiplets

21. 4) Bands and isomers around A=250
Pretty robust

22. Condensation of Octupole phonons + Two phonon - One phonon + 27
X. Wang, R.V.F. Janssens, I.
Wiedenhoever et al. to be published.
Preliminary + 27

27. 5) Weak symmetry breaking
Chiral vibrations
Rotation induced condensation of octupole phonons
Tidal waves
How does the nucleus rotate?

28. Rotation induced condensation of octupole phonons
S. Frauendorf
Phys. Rev. C 77, (07)
Two components: Quadrupole +Octupole 23

29. Weak coupling + Two phonon - One phonon + 27
X. Wang, R.V.F. Janssens, I.
Wiedenhoever et al. to be published.
Preliminary + 27

30. Intermediate coupling
missing 27

31. Strong coupling 28

32. 1.Weakly oriented nuclei – tidal waves
S. Frauendorf, Y. Gu, arXiv , PRL, in preparation
Mean field:
rigid spherical
soft
rigid deformed
-condensation of
quadrupole phonons
-very soft rotor
Tidal wave 4
Yrast line
irregular
multi p-h
regular
w weakly increases with I
regular
w proportional to I

34. How does orientation come about?
Orientation of the gyroscopes
Deformed density / potential
Nucleonic
orbitals –
gyroscopes
Deformed potential aligns the
partially filled orbitals
Partially filled orbitals are
highly tropic
Nuclus is oriented –
rotational band
Well deformed 5

35. How does the nucleus rotate?
Angular momentum is generated
by alignment of the spin of the
orbitals with the rotational axis
Gradual – rotational band
Abrupt – band crossing, no bands
Moments of inertia for I>20
(no pairing) differ strongly from
rigid body value
Microscopic cranking is the way to calculate the response of the gyros. Quantization of spin of orbits responsible for difference.
Microscopic cranking
Calculations do well in
reproducing the moments
of inertia.
With and without pairing. 7
M. A. Deleplanque et al.
Phys. Rev. C69, (2004)

36. What have we learned?
Liquid drop + shell structure in rotating WS – like potential account for energies and lifetimes. Time-odd terms of the mean field?
Deviations from classical droplet are dramatic.
Symmetries of the mean field play a central role
Dynamical (weak) symmetry breaking is common.

37. 6)The future Combination of large Gamma ray arrays
with stable and radioactive beams

38. The challenges (incomplete)
fission
Map out the new shells I
Rotation induced T=0 pairing?
Ergodic bands
(Mottelson, Matsuo,Yoshida)
p-dripline
Cold proton emission from high spin states
Dynamics of angular
momentum reorientation
A=130
SHE A
Increased stability of
High spin isomers
N-Z
n-dripline
Terra incognita
Decoupling of mass from charge
Increased stability of K-isomers
Single particle states from isomers