REINA() DE TRABALHO SOBRE FiSICA NUCLEAR NO BRASIL

XX RTFNI3 - Resumos 39
multiplicity is strongly sensitive to the multiparticle dynamics.
Kaons have already been recently observed as being
produced in the y -proton reactions[5,6,7]. An investigation
for the 7-A reaction have been carried out in
order to explore new informations about the effects of
the nuclear medium in the photon absorption mechanism.
The main observable of the present calculation
is the kaon multiplicity and photonuclear kaon production
cross section. The results obtained show that the
Fermi motion and nuclear binding energy has a remarkable
effect for kaon production near threshold.
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The Ion-Ion Potential and Neutron Transfer
Processes in the 180 .f 58'60 Ni Systems at
Sub-Harriet Energies'
E. S. Rossi JR, C. CHAVION, D. PEREIRA, C. P.
SILVA, G. ftsminEz
Laboratdrio Peibitron, Institute de Pisiea da Universidade
de Sao Paulo,Caixa Postal 66318, 05889-970, .7iin Paulo,
SP, Brazil.
Recently we have presented a realiable determination
of the ion-ion potentials for the IGO + 58' 6" 2."Ni
systemsL 1,21 , at the large interacting radius (9.5 < k <
11.5 fm),by measuring the elastic (1% precision) and
inelastic (2±) cross sections at sub-barrier energies. In
the present work, we have extended those studies to the
180 + systems, and we have investigated: 0 the
influence of the neutron transfer processes in the determination
of the ion-ion potentials using the coupled
channel (CC) analysis of the data, ii) the comparison
between the resulting CC ion-ion potentials and the
theoretical calculations using the Double-Folded method
and Shell-Model densities, iii) possible influence of
the two neutron transfer process in the measured fusion
cross sections for the 56. 180 + 58,6°NiN.
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Jr., C. Ramirez, A. M. forges and C. A. Aguiar, Phys.
Rev. C55, 3155 (1997).
°Partially supported by FINEY. CNN' and NAPES?.