Pairing Effects in Nuclear Fusion Reaction

We simulate a heavy-ion collision using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) treating pairing correlation in the three-dimensional coordinate space. We apply the Cb-TDHFB to 22O+22O collision with a contact-type pairing energy functional, and compare results of Cb-TDHFB and TDHF to investigate the effects of pairing correlations in nuclear fusion. Our results seem to indicate that pairing effects do not increase the fusion cross section in this system.Comment: 4 pges, 2 figures, Proceedings of the 12th Asia Pacific Physics Conference(APPC12

Low-lying 2+^+ states generated by pnpn-quadrupole correlation and N=28N=28 shell quenching

The quadrupole vibrational modes of neutron-rich $N$=28 isotones ($^{48}$Ca, $^{46}$Ar, $^{44}$S and $^{42}$Si) are investigated using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory with several choice of energy density functionals, including nuclear pairing correlation. It is found that the quenching of $N$=28 shell gap and the proton holes in the $sd$-shell trigger quadrupole correlation and increase the collectivity of the low-lying 2$^+$ state in $^{46}$Ar. It is also found that the pairing correlation plays an important role to increase the collectivity. We also demonstrate that the same mechanism to enhance the low-lying collectivity applies to other $N$=28 isotones $^{44}$S and $^{42}$Si, and it generates a couple of low-lying 2$^+$ states which can be associated with the observed $2^+$ states.Comment: 7 page and 4 figure

Systematic study of low-lying E1 strength using the time-dependent mean field theory

We carry out systematic investigation of electric dipole (E1) mode from light to heavy nuclei, using a new time-dependent mean field theory: the Canonical-basis Time-Dependent Hartree-Fock-Bogoliubov (Cb-TDHFB) theory. The Cb-TDHFB in the three-dimensional coordinate space representation can deal with pairing correlation and any kind of deformation in the time-dependent framework. We report the neutron-number dependence of the low-energy E1 mode for light (A 100) around N = 82.Comment: 3 pages, 2 figures, The 11th International Symposium on Origin of Matter and Evolution of Galaxies (OMEG11) proceeding

Thick-target yields of radioactive targets deduced from inverse kinematics

The thick-target yield (TTY) is a macroscopic quantity reflected by nuclear reactions and matter properties of targets. In order to evaluate TTYs on radioactive targets, we suggest a conversion method from inverse kinematics corresponding to the reaction of radioactive beams on stable targets. The method to deduce the TTY is theoretically derived from inverse kinematics. We apply the method to the natCu(12C,X)24Na reaction to confirm availability. In addition, it is applied to the 137Cs + 12C reaction as an example of a radioactive system and discussed a conversion coefficient of a TTY measurement.Comment: 8 pages, 3 figures, Accepted to Nuclear Instruments and Methods in Physics Research

Time-dependent density-functional studies on strength functions in neutron-rich nuclei

The electric dipole (E1) strength functions have been systematically calculated based on the time-dependent density functional theory (TDDFT), using the finite amplitude method and the real-time approach to the TDDFT with pairing correlations. The low-energy E1 strengths in neutron-rich isotopes show peculiar behaviors, such as sudden enhancement and reduction, as functions of the neutron numbers.They seem to be due to the interplay between the neutron shell effect and the deformation effect.Comment: 8 pges, 2 figures, Proceedings of the 5th International Conference on "Fission and properties of neutron-rich nuclei" (ICFN5), Sanibel Island, Nov. 4-10, 201