Pairing correlations in deformed nuclei close to the neutron drip line

Study of pairing correlations in nuclei close to the neutron drip line is an extensively investigated subject currently. The presence of loosely-bound neutrons and the coupling to the nearby continuum enhance di-neutron correlations [1]. On the other hand, pairing correlations cause the change of the spatial structure of quasiparticle wave functions, and the correlations among the resultant two-quasiparticle states of low-$\ell$ neutrons lead to the large transition strength of the low-frequency shape oscillations in neutron drip line nuclei [2]. At present, however, these studies are restricted only for spherical nuclei. In my talk, by solving Hartree-Fock-Bogoliubov equation in coordinate space allowing axially symmetric deformation, the pairing effects in deformed neutron drip line nuclei is analyzed paying special attention to neutrons with small $\Omega$, that is the projection of the single-particle angular momentum along the symmetry axis, in connection with the possibility of neutron halos in medium mass and heavier neutron-rich nuclei.\\ \noindent [1] M. Matsuo, K. Mizuyama, and Y. Serizawa, preprint nucl-th/0408052.\\ \noindent [2] M. Yamagami, preprint nucl-th/0504059.