Semi-realistic nucleon-nucleon interactions with improved neutron-matter properties

New parameter-sets of the semi-realistic nucleon-nucleon interaction are developed, by modifying the M3Y interaction but maintaining the tensor channels and the longest-range central channels. The modification is made so as to reproduce microscopic results of neutron-matter energies, in addition to the measured binding energies of doubly magic nuclei including $^{100}$Sn and the even-odd mass differences of the Z=50 and N=82 nuclei in the self-consistent mean-field calculations. Separation energies of the proton- or neutron-magic nuclei are shown to be in fair agreement with the experimental data. With the new parameter-sets M3Y-P6 and P7, the isotropic spin-saturated symmetric nuclear matter remains stable in the density range as wide as $\rho\lesssim 6\rho_0$, while keeping desirable results of the previous parameter-set on finite nuclei. Isotope shifts of the Pb nuclei and tensor-force effects on shell structure are discussed.Comment: 18 pages including 7 figure

Using Janus VR with Oculus Rift to enhance Second Language Learning: Analyze the Correlation Between the Sense of Immersion and Learning Second Languages

I created a Virtual Reality (VR) website in Janus VR, a VR web browser, to enhance second language learnings. By using Skype and this VR website in Janus VR, it is possible to create a business to teach second languages, by which students do not need to make an appointment to meet up with teachers, and while students taking a lesson they can see teacher’s avatars. This research is to find the correlation between the sense of immersion and learning second languages. In order to analyze the actual effect of learning second languages in a virtual reality setting, specifically Janus VR, an experiment was conducted to measure the following: change of the trade-off effect by learning vocabulary in virtual reality and the effect of the sense of immersion in learning second languages. Each subject was given two lectures to learn basic Japanese words. One lecture is the traditional online-chat based lesson in which subjects will talk to the teacher via Skype. The other lecture is taught in one of Janus VR’s website I created specifically for learning Japanese. In this environment, subjects talked to the teacher’s avatar via Skype. After each lecture, a short quiz is taken by subjects to compare respective lectures; the online-chat based lecture and Janus VR based lecture. Also, subjects were given an interview to evaluate the importance of 24/7 accessibility of the virtual reality web browser for continuous study

Further evidence for three-nucleon spin-orbit interaction in isotope shifts of Z=magicZ=\mathrm{magic} nuclei

It was pointed out [Phys. Rev. C \textbf{91}, 021302(R)] that the isotope shifts of the Pb nuclei, the kink at $N=126$ in particular, can be well described by the Hartree-Fock-Bogolyubov calculations if a density-dependent LS interaction derived from the $3N$ interaction is incorporated. Effects of the density-dependence in the LS channel on the isotope shifts are extensively investigated for the Ca, Ni and Sn isotopes, using the semi-realistic M3Y-P6 interaction and its LS modified variant M3Y-P6a, as in the Pb case. It is found that almost equal charge radii between $^{40}$Ca and $^{48}$Ca are reproduced, as well as the isotope shifts in a long chain of the Sn nuclei, owing to the density-dependence in the LS channel. A kink is predicted at $N=82$ for the isotope shifts of the Sn nuclei, in clear contrast to the interactions without the density-dependence.Comment: 7 pages including 4 figures, to appear in PR

Robots and Privacy in Japanese, Thai and Chinese Cultures. \ud Discussions on Robots and Privacy as Topics of Intercultural Information Ethics in ‘Far East’

In this paper, I will analyze ‘cultural meanings and values’ associated with some of the important IIE(intercultural information ethics) topics in ‘Far East, ’i.e. ‘human and robot interaction(HRI)’ and ‘privacy.’ By focusing on these relatively newly emerging topics in ‘Far East,’ I will attempt to make the cultural Ba (locus/place where different\ud meanings of things, events, people’s experiences come together; or frameworks for understanding meanings of phenomena and events) visible through analysis of research data done in Japan, Thailand and China in the past several years. The research data shown in this paper suggest that we can’t understand people’s attitudes toward robots and privacy in ‘Far East’ without taking into consideration people’s broader views on ‘what is a good life?’ and ‘what is a virtuous life?

RPA calculations with Gaussian expansion method

The Gaussian expansion method (GEM) is extensively applied to the calculations in the random-phase approximation (RPA). We adopt the mass-independent basis-set that has been tested in the mean-field calculations. By comparing the RPA results with those obtained by several other available methods for Ca isotopes, using a density-dependent contact interaction and the Woods-Saxon single-particle states, we confirm that energies, transition strengths and widths of their distribution are described by the GEM bases to good precision, for the $1^-$, $2^+$ and $3^-$ collective states. The GEM is then applied to the self-consistent RPA calculations with the finite-range Gogny D1S interaction. The spurious center-of-mass motion is well separated from the physical states in the $E1$ response, and the energy-weighted sum rules for the isoscalar transitions are fulfilled reasonably well. Properties of low-energy transitions in $^{60}$Ca are argued in some detail.Comment: 30 pages including 12 figure