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Study of Giant Pairing Vibrations with neutron-rich nuclei

Lorenzo Fortunato
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Abstract

We investigate the possible signature of the presence of giant pairing states at excitation energy of about 10 MeV via two-particle transfer reactions induced by neutron-rich weakly-bound projectiles. Performing particle-particle RPA calculations on $^{208}$Pb and BCS+RPA calculations on $^{116}$Sn, we obtain the pairing strength distribution for two particles addition and removal modes. Estimates of two-particle transfer cross sections can be obtained in the framework of the 'macroscopic model'. The weak-binding nature of the projectile kinematically favours transitions to high-lying states. In the case of $(~^6He, \~^4He)$ reaction we predict a population of the Giant Pairing Vibration with cross sections of the order of a millibarn, dominating over the mismatched transition to the ground state.

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Lorenzo Fortunato. 2002-06-04. Study of Giant Pairing Vibrations with neutron-rich nuclei. https://doi.org/10.1134/1.1601748

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