Eur. Phys. J. A (2005) 25: 569-570
https://doi.org/10.1140/epjad/i2005-06-130-1

ENAM 2004

Collective excitations induced by pairing anti-halo effect

Heavy Ion Nuclear Physics Laboratory, RIKEN, 351-0198, Japan

^* e-mail: yamagami@riken.jp

Received: 10 December 2004
Accepted: 11 March 2005
Published online: 24 June 2005

Abstract

We emphasize a special interplay of loosely-bound neutrons with small orbital angular momentum ℓ and self-consistent pairing correlations for low-lying collective vibrational excitations in neutron drip line nuclei. Change of the spatial structure in quasiparticle wave functions by self-consistent pairing correlations leads to the broad localization of two-quasiparticle states with low-ℓ neutrons. We show that the broad localization can cause the enhancement of the low-lying collectivity. By performing HFB plus quasiparticle random phase approximation (QRPA) calculation for the first 2⁺ states in neutron rich Ni isotopes, the unique role of self-consistent pairing correlations is examined. Finally we make a comment on deformation effects for low-lying vibrational excitations in neutron drip line nuclei.