Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
福井 徳朗; 延与 佳子*; 菊地 右馬*; 松本 琢磨*; 緒方 一介*; 須原 唯広*; 谷口 億宇*; 八尋 正信*
no journal, ,
First, we show that, for the coupled-channels Born approximation (CCBA) analysis of the reaction, it is essentially important to consider the transfer process from (to) the breakup state of (). These transfer process called the breakup transfer is never taken into account in the distorted-wave Born approximation (DWBA). Next, the importance of the CCBA model is given for the description of the -transfer reaction, of which, so far the DWBA has been failed to produce the cross section to be consistent with measured one. Our calculation greatly improves coincidence of the calculation with the data and enables us to discuss the surface distribution of the -cluster structure of . Finally, how to describe transfer reaction to continuum state, such as , is presented. It is known that the integration in the transition matrix ( matrix) of such reaction does not converge. To avoid this problem, the prior form of the matrix, for which the CCBA model is required to calculate the approximately exact wave function of the final channel, is employed.
Orlandi, R.
no journal, ,
Transfer reactions are a valuable tool to study the evolution of shell structure away from stability. In particular, studies of nuclei in the proximity of exotic doubly-magic nuclei like Ni and Sn are key systems to test our theoretical understanding. Single-neutron states in the Z = 30, N = 49 isotope Zn have been populated using the Zn(d,p)Zn transfer reaction in inverse kinematics at REX-ISOLDE, CERN. The experimental setup allowed the combined detection of protons ejected in the reaction, and of rays emitted by Zn. From the analysis of -ray and proton data, low-lying states in Zn were observed and identified. Comparison with large-scale shell-model calculations permits to constrain the size of the N=50 shell gap in Ni. Neutron-hole states in Sn were populated using the Sn(d,t)Sn reaction at Oak Ridge National Laboratory. Measured cross sections and their impact of single-hole energies in Sn will also be presented.
西尾 勝久; 廣瀬 健太郎; 牧井 宏之; Orlandi, R.; 塚田 和明; Vermeulen, M. J.; Andreyev, A. N.; 千葉 敏; Tsekhanovich, I.*; 大槻 勤*
no journal, ,
We are promoting a campaign to study multi-nucleon transfer reactions to populate excited states in neutron-rich actinide nuclei which cannot be accessed by particle capture and/or fusion reactions. Main purpose of this program is to study fission in new region of chart of nuclei. As a first step we studied reactions using the O beam ( 9 MeV/u) and actinide target nuclei such as U, Np, Cm. The experiment was carried out at the tandem facility of Japan Atomic Energy Agency. Ejectile nuclei generated in the reaction were identified by a newly developed silicon E-E detectors. Using this detector, clear separation of oxygen isotopes (O) was obtained as well as lighter element isotopes (Be, B, C, N). The number of produced nuclei amounted to more than fifteen in one reaction. Two fragments emitted in multi-nucleon transfer fission were detected by multi-wire proportional counters, and the fragment mass distributions were obtained for each isotopes. The measured FFMDs agreed with a calculation based on the fluctuation-dissipation model up to about excitation energy 30 MeV. Measurement of fission fragment angular distribution relative to the recoil direction suggested the increase of the spin with the number of transferred nucleons.