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The structure of the isovector dipole resonance in neutron-rich calcium isotope, 60 Ca, has been investigated by implementing a careful treatment of the differences of neutron and proton radii in the continuum random phase approximation (RP A).The calculations have taken into account the current estimates of the neutron skin.The estimates of the escape widths for direct neutron decay from the pygmy dipole resonance (P DR) were shown rather wide, implicating a strong coupling to the continuum. The width of the giant dipole resonance (GDR) was evaluated, bringing on a detailed discussion about its microscopic structure.PACS numbers: 21.10. Pc, 24.30.Cz, 24.30.Gd I. INTRODUCTIONThe investigation of the nuclei lying far from the β − stability line has been an interesting and active field of the nuclear physics in the last two decades. In that region, a great number of exotic features are observed like halo/skin formation, intruders levels, new magic numbers and new kinds of collective excitation, the so-called soft and pygmy resonances.These observations have forced the review of successful theoretical tools in nuclei around the β − stability valley [1,2,3,4].The description of the microscopic structure of the exotic nuclei is a current topic of study and several recent works had the concern of describing the giant resonance (GR) in neutronrich nuclei. The main questions treated are the giant dipole resonance (GDR) behavior and the appearance of the pygmy dipole resonance (P DR) in a nucleus with large ratio of neutron to proton number (N/Z). The P DR appears in medium and heavy neutron-rich nuclei, and, within the hydrodynamic sense, they are probably due to oscillation of the

The separation energy and half-life of some heavy proton emitting nuclei, and the single-particle structure of the unbound 11 N , have been evaluated by implementing a careful numerical treatment to solve Schrödinger equation in a continuum discretization context. The basic scheme behind the method consists in using the ground-state proton emitter in connection with an isolated single-particle resonance.Keywords: Decay by proton emission; lifetimes; single-particle levels. Recently, several unstable proton emitting nuclei with medium and heavy masses [1,2,3,4,5,6,7,8,9,10,11] have been discovered and are attracting much attention in both theoretical and experimental nuclear physics. In the light mass limit unbound 11 N is another well studied proton emitter nucleus which presents some intriguing phenomena such as the s 1/2 intruder level and the 11 Be mirror states discussed in the recent literature [12,13,14].The parent nucleus decays by proton emission in a quantum tunneling process. In a first approximation we can treat this problem as an unbound proton + core system in which the ground-states instabilities are studied from the single-particle resonance point of view. These

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