1982
Research of high energy collective
states at high excitation energy in
nuclei
N. Alamanos, J. Arvieux, B. Berthier, B.
Bonin, G. Bruge, M. Buenerd, J. Dechargé,
H. Faraggi, D. Gogny, Y. Terrien
Collective excitation modes in nuclei
GDR : a well known giant resonance
GQR : another well known giant
resonance
RPA calculations predict the existence of collective high energy modes in nuclei
Special interest for monopole modes, because they give access to the
compressibility of nuclear matter
Transition densities
Bonin
Macro
Gogny-Dechargé
RPA
Satchler
Macro
Experiment : (alpha, alpha’) inelastic scattering
on 208Pb, 116Sn, 58Ni; Ealpha = 430, 480 MeV
Detection
One excitation spectrum…
…Many excitation spectra
Note the ripples of the angular distribution of
the cross section
Multipole decomposition
Calculation : Transition densities (RPA) transition potentials Coupled channel
calculation (ECIS, N. Alamanos, J. Raynal)  angular distribution of cross section 
multipolarity of the excited states can be deduced from the oscillations of the cross
section
Same response function extracted for
E= 340 and 480 MeV
Agreement of experiment with RPA
calculations
Conclusions
• High multipolarity giant resonances predicted
by RPA calculations have been found.
• The nucleus still behaves collectively even at
high excitation energy!
Epilogue
• Collaboration Saclay-B3 (J. Dechargé)
continued with the search of other resonances
with polarized deuterons (PhD Th. Mandon).