On the basis of the association theory of nuclear structure, we have studied the (t, p) reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron as...On the basis of the association theory of nuclear structure, we have studied the (t, p) reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron association is acceptable if the time during which the association maintains its structure, is large compared with the time when neutrons are in a dissociated form, and there is no exchange of nucleons between fragments associations. The cross section is written as a product of two factors, one is the spectroscopic factor which reflects the nature of the nuclear structure concerned and the other describes the process in which the target nucleus captures two nucleons as a cluster into an orbit which is characterized by a form factor. In the argument, that the radial wave function of two neutrons which form association captured nuclei close to each other, this leads to the formation of bineutron association on the nuclei surface. In this approach, the proton is emitted at the same point, which is captured bineutron association.展开更多
The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tens...The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tensor, spin orbit and quadratic spin orbit terms with Gaussian radial dependence. The parameters of these interactions are so chosen in such a way that they represent the long-range attraction and the short-range repulsion of the nucleon-nucleon interactions. These parameters are so chosen to reproduce good agreement between the calculated values of the binding energy, the root mean-square radius, the D-state probability, the magnetic dipole moment and the electric quadrupole moment of the deuteron nucleus. The variation method is then used to calculate the binding energy of triton by varying the oscillator parameter which exists in the nuclear wave function. The obtained nuclear wave functions are then used to calculate the root mean-square radius and the magnetic dipole moment of the triton.展开更多
We present nuclear physics programs based on the planned experiments using rare isotope beams(RIBs) for the future Korean Rare Isotope Beams Accelerator facility(KRIA). This ambitious facility has both an Isotope Sepa...We present nuclear physics programs based on the planned experiments using rare isotope beams(RIBs) for the future Korean Rare Isotope Beams Accelerator facility(KRIA). This ambitious facility has both an Isotope Separation On Line(ISOL) and fragmentation capability for producing RIBs and accelerating beams of wide range mass of nuclides with energies of a few to hundreds Me V per nucleon. Low energy RIBs at Elab = 5 to 20 Me V per nucleon are for the study of nuclear structure and nuclear astrophysics toward and beyond the drip lines while higher energy RIBs produced by inflight fragmentation with the reaccelerated ions from the ISOL enable to explore the neutron drip lines in intermediate mass regions. The planned programs have goals for investigating internal structures of the exotic nuclei toward and beyond the nucleon drip lines by addressing the following issues: how the shell structure evolves in areas of extreme proton to neutron imbalance; whether the isospin symmetry maintains in isobaric mirror nuclei at and beyond the drip lines; how two-proton radioactivity affects abundances of the elements; what the role of the continuum states including resonant states above protondecay threshold in exotic nuclei is in astrophysical nuclear reaction processes, and how the nuclear reaction rates triggered by unbound proton-rich nuclei make an effect on rapid proton capture processes in a very hot stellar plasma.展开更多
The contributions of two-photon exchange in the process e+ + e-→ p + p including N and △ intermediate states are estimated in a simple hadronic model. The corrections to the unpolarized cross section as well as t...The contributions of two-photon exchange in the process e+ + e-→ p + p including N and △ intermediate states are estimated in a simple hadronic model. The corrections to the unpolarized cross section as well as to the polarized observables Px and Px are evaluated. The results show the corrections to unpolarized cross section are small and the angle dependence becomes weak at small s after considering the N and △(1232) contributions simultaneously, while the correction to Px is enhanced.展开更多
文摘On the basis of the association theory of nuclear structure, we have studied the (t, p) reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron association is acceptable if the time during which the association maintains its structure, is large compared with the time when neutrons are in a dissociated form, and there is no exchange of nucleons between fragments associations. The cross section is written as a product of two factors, one is the spectroscopic factor which reflects the nature of the nuclear structure concerned and the other describes the process in which the target nucleus captures two nucleons as a cluster into an orbit which is characterized by a form factor. In the argument, that the radial wave function of two neutrons which form association captured nuclei close to each other, this leads to the formation of bineutron association on the nuclei surface. In this approach, the proton is emitted at the same point, which is captured bineutron association.
文摘The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tensor, spin orbit and quadratic spin orbit terms with Gaussian radial dependence. The parameters of these interactions are so chosen in such a way that they represent the long-range attraction and the short-range repulsion of the nucleon-nucleon interactions. These parameters are so chosen to reproduce good agreement between the calculated values of the binding energy, the root mean-square radius, the D-state probability, the magnetic dipole moment and the electric quadrupole moment of the deuteron nucleus. The variation method is then used to calculate the binding energy of triton by varying the oscillator parameter which exists in the nuclear wave function. The obtained nuclear wave functions are then used to calculate the root mean-square radius and the magnetic dipole moment of the triton.
文摘We present nuclear physics programs based on the planned experiments using rare isotope beams(RIBs) for the future Korean Rare Isotope Beams Accelerator facility(KRIA). This ambitious facility has both an Isotope Separation On Line(ISOL) and fragmentation capability for producing RIBs and accelerating beams of wide range mass of nuclides with energies of a few to hundreds Me V per nucleon. Low energy RIBs at Elab = 5 to 20 Me V per nucleon are for the study of nuclear structure and nuclear astrophysics toward and beyond the drip lines while higher energy RIBs produced by inflight fragmentation with the reaccelerated ions from the ISOL enable to explore the neutron drip lines in intermediate mass regions. The planned programs have goals for investigating internal structures of the exotic nuclei toward and beyond the nucleon drip lines by addressing the following issues: how the shell structure evolves in areas of extreme proton to neutron imbalance; whether the isospin symmetry maintains in isobaric mirror nuclei at and beyond the drip lines; how two-proton radioactivity affects abundances of the elements; what the role of the continuum states including resonant states above protondecay threshold in exotic nuclei is in astrophysical nuclear reaction processes, and how the nuclear reaction rates triggered by unbound proton-rich nuclei make an effect on rapid proton capture processes in a very hot stellar plasma.
基金Supported by National Sciences Foundations of China (10475088, 10747118)
文摘The contributions of two-photon exchange in the process e+ + e-→ p + p including N and △ intermediate states are estimated in a simple hadronic model. The corrections to the unpolarized cross section as well as to the polarized observables Px and Px are evaluated. The results show the corrections to unpolarized cross section are small and the angle dependence becomes weak at small s after considering the N and △(1232) contributions simultaneously, while the correction to Px is enhanced.