Presentation on theme: "Exotic Shapes and High Spin physics with Intense Stable Beams."— Presentation transcript:
Exotic Shapes and High Spin physics with Intense Stable Beams
Shell structure far from spherical magic numbers Which is the adopted deformation and how it changes with spin and energy ? What are the active orbitals and their correlations ? How is spin generated ? How much spin can the nucleus sustain ?
Superdeformed world = more than 250 SD rotational bands Octupole vibrations Gyromagnetic factors Triaxial bands + wobbling Band termination Particle decay Large Shell Model calculations SD binding energies
Jacobi shape transition Rotational damping Hyperdeformation Chaos Assisted tunneling superdeformation fission SPIN ENERGY GDR Tetrahedral nuclei A domain rich of new exotic phenomena to be discovered and studied HIGH L
HLHD Experiment EUROBALL: 64 Ni + 64 Ni 261 MeV: 52 keV ridge appears 4 x 52 keV Int.: 993 Int.: 1367 Ridge intensity ~5 x 10 -5
Search for discrete-line HD spectra Euroball, ) E ( ~ 52 keV A strange feeling of déjà vu
Triaxiality and Wobbling TSD4 TSD1 TSD2 TSD3 Relative population TSD1:10% TSD2:3% TSD3:1.2% TSD4:0.9% Experimental results in 163 Lu The best Wobbler D.R. Jensen et al., Phys. Rev. Lett. 89 (2002), 142503.
Gates: Time of Flight Residues nuclei ( 42 Ca) Low energy multiplicity Theory: (Jacoby shape transition) LSD model + Coriolis Splitting A. Maj et al. Nucl. Phys. A731 (2004) 319
Fusion evaporation reactions I beam ~ 10 - 10 p/s Limitation: counting rate in the Germanium detectors and/or common acquisition dead-time 10 11 Resolving power ~ 10 -4 Limitation: current arrays (5-10 pnA) High spin states populated in Fighting to observe VERY WEAK signals…
Gamma-ray Detector Development Advances in detector technology have resulted in new discoveries. Innovations have improved detector performance. –Energy resolution –Efficiency –Peak-to-total ratio –Position resolution –Directional information –Polarization –Auxiliary detectors Tracking is feasible, will provide new opportunities and meet the challenges of new facilities. Central Role in Nuclear Physics
high granularity + digital electronics AGATA will be able to handle 10 – 100 times more beam Advanced GAmma Tracking Array N evt = N p x N t x x d