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This combination of future displays and future cameras copies 4D light fields just as a 2D copy machine reproduces text and images on a sheet of paper. Attendees can use the system to capture light fields and copy "real" objects.

Gamow-Teller and dipole transitions to final states in $^{13}\mathrm{B}$ were studied via the $^{13}\mathrm{C}(t,^{3}\mathrm{He})$ reaction at ${E}_{t}=115A$ MeV. In addition to the strong Gamow-Teller transition to the $^{13}\mathrm{B}$ ground state, a weaker Gamow-Teller transition to a state at 3.6 MeV was found. This state was assigned a spin-parity of $3/{2}^{\ensuremath{-}}$ by comparison with shell-model calculations using the WBP and WBT interactions which were modified to allow for mixing between $n\ensuremath{\hbar}\ensuremath{\omega}$ and $(n+2)\ensuremath{\hbar}\ensuremath{\omega}$ configurations. This assignment agrees with a recent result from a lifetime measurement of excited states in $^{13}\mathrm{B}$. The shell-model calculations also explained the relatively large spectroscopic strength measured for a low-lying $1/{2}^{+}$ state at 4.83 MeV in $^{13}\mathrm{B}$. The cross sections for dipole transitions up to ${E}_{x}$$(^{13}\mathrm{B})=20$ MeV excited via the $^{13}\mathrm{C}(t,^{3}\mathrm{He})$ reaction were also compared with the shell-model calculations. The theoretical cross sections exceeded the data by a factor of about 1.8, which might indicate that the dipole excitations are ``quenched''. Uncertainties in the reaction calculations complicate that interpretation.

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

The deuteron to proton polarization transfer coefficients ${K}_{\mathit{yy}}^{{y}^{'}}$ and ${K}_{y}^{{y}^{'}}$ together with the deuteron analyzing powers are measured in three coplanar configurations of the deuteron-proton breakup reaction with a 135-MeV/nucleon polarized deuteron beam at the RIKEN Accelerator Research Facility. The data are compared with theoretical predictions based on exact solutions of the three-nucleon ($3N$) Faddeev equations with high-precision nucleon-nucleon ($\mathit{NN}$) forces, alone or combined with two $3N$ force (3NF) models, the $2\ensuremath{\pi}$-exchange Tucson-Melbourne${}^{'}(99)$ (${\mathrm{TM}}^{'}99$) and Urbana IX. Large 3NF effects have been found for all the measured observables. Predicted effects are supported by the data, with the exception of the vector analyzing power ${A}_{y}^{d}$. For this observable, theory based on only $\mathit{NN}$ forces is sufficient to explain the data. The behavior of the breakup analyzing powers is found to be different from the corresponding observables in elastic nucleon-deuteron scattering.

We propose a method to increase the viewing resolution of an autostereoscopic display without increasing the density of microlenses. Multiple projectors are used for the projection images to be focused and overlaid on a common plane in the air behind the microlens array. The multiple overlaid projection images yield multiple light spots inside the region of each elemental lenslet of the microlens array. This feature provides scalable high resolution images by increasing the number of projectors.

Gamow-Teller (GT) unit cross sections, ${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{GT}}$, are obtained at 198 and 297 MeV by measuring the double differential cross sections at ${0}^{\ifmmode^\circ\else\textdegree\fi{}}$ for the $(p,n)$ reaction on $^{58}\mathrm{Ni}$, $^{70}\mathrm{Zn}$, $^{114}\mathrm{Cd}$, $^{118}\mathrm{Sn}$, and $^{120}\mathrm{Sn}$. The mass dependence of ${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{GT}}$ and the ratio of ${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{GT}}$ to the Fermi unit cross section, ${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{F}}$, $({R}^{2})$ are also derived in the mass region of $58\ensuremath{\leqslant}A\ensuremath{\leqslant}120$. The ${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{GT}}$ value for $^{90}\mathrm{Zr}$ at 297 MeV interpolated using the $A$-dependence obtained herein agrees with that used in a previous analysis where the GT transition strength over a wide energy region up to the continuum was discussed. However, the deduced $^{64}\mathrm{Ni}$${\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\sigma}}}_{\mathrm{GT}}$ value at 198 MeV is 20% smaller than that obtained from the analysis of a previous $(n,p)$ measurement. The present ${R}^{2}$ values in the mass region heavier than $^{42}\mathrm{Ca}$ are larger than those in the region up to $^{42}\mathrm{Ca}$ and increase as a function of $A$.

Spectral measurements of intermediate-energy neutrons (i.e., En ≤ 65 MeV) transmitted through iron, lead, graphite, and concrete shields are described. Concurrently, transmitted spectra of associat...

Measurements of neutron response functions of a 3 in. × 3 in. NE-213 scintillator were made for neutron energies from 10 MeV to 73 MeV using neutrons from a quasi-monoenergetic neutron source of p- 7 Li and a white source from thick Be and Cu targets. Neutrons sampled into small energy bins by TOF signals were utilized in the response measurements. Response functions calculated by the Monte Carlo method were compared with the measured data, thus clearing problems in the calculation model. Based on the measured and calculated data, a new response matrix which covered from 0 to 76 MeV was constructed. The matrix was successfully applied to unfold a pulse-height spectrum of up to several tens of MeV neutrons that were transmitted through a 50 cm concrete shield.

The technical aspects of measurements of (n, p) reactions on 1 H and 2 H at 58 MeV using a magnetic spectrometer are described. By using a veto and trigger counter system at the target position and a ray-trace type wire counter at the focal plane of the spectrometer, low background measurements were realized. The shape of the proton continuum spectrum at the n-n final-state interaction region from the 2 H(n, p)2n reaction at 0° was explained by an impulse-approximation calculation taking the experimental finite energy resolution into account.

A case of adenoid cystic carcinoma of the breast is reported. A 70-year-old woman was referred to our clinic with the chief complaint of right breast pain. The impression of the mass was chronic mastopathy, but a possible malignancy was suspected ultrasonographycally. Excisional biopsy and pathological examination revealed an adenoid cystic carcinoma. Patey operation was performed, no metastasis to axillary lymph node being found. Histologically, the tumor was characterized by “cysts” with a cribriform pattern. Histochemically, hyaline material inside “cysts” were alcian blue-positive and PAS-negative or weakly positive, and contents of the duct structures gave a positive reaction with PAS but negative with alcian blue. Immunohistochemically, CEA (carcinoembryonic antigen) and secretory component were disclosed in the duct structures, but none in the “cysts”.

A systematic study of three-nucleon force (3NF) effects in break-up reactions has been carried out at KVI at several energies. In this article, the p + d -> p + p + n reaction with a polarized-proton beam of 190 MeV will be discussed. The experiment was performed by exploiting a new detector called BINA. Some results for high-precision vector analyzing powers and differential cross sections are presented and compared with state-of-the-art Faddeev calculations with or without 3NF.

We searched for the neutrino-less double-β decay(0νββ) of 48 Ca by using CaF 2 (Eu) scintillators. Analysis of their pulse shapes was effective to reduce backgrounds. No events are observed in the Q ββ value region for the data of 3394 kg day. It gives a lower limit (90% confidence level) of T 0νββ ½ > 2.7 x 10 22 year for the half-life of 0νββ of 48 Ca. Combined with our previous data for 1553 kg day [I. Ogawa et al., Nucl. Phys. A730, 215 (2004)], we obtained a more stringent limit of T 0νββ ½ > 5.8 × 10 22 year.

We have measured for the first time yields of both neutron‐proton and neutron‐neutron pairs emitted from the non‐mesonic weak decay of the Λ5He and Λ12C hypernuclei, produced via the (π+,K+) reaction. From the yields of both the back‐to‐back np‐pair events and nn‐pair events, we have directly determined the ratio of the neutron‐ and proton‐induced decay widths, Γn(Λn→nn)/Γp(Λp→np). Meanwhile, we have also determined the quenching of the observed numbers of single nucleons and coincident nucleon pairs compared with theoretical calculations. Our results suggest that contributions from the two‐nucleon‐induced three‐body process ΛNN→NNN are significant.

A discussion is presented of the dynamics underlying three-body nuclear forces, with emphasis on changes which occurred over several decades., Comment: Talk given at the FM50 symposium, Tokyo, October 2007

Data for the deuteron analyzing powers in the dd→3Hen(3Hp) reactions obtained at 140–270 MeV are discussed. The observed negative sign of the tensor analyzing powers Ayy, Axx and Axz at small angles clearly demonstrate the sensitivity to the ratio of the D and S state components of the 3He wave function. The behavior of the tensor analyzing powers at backward angles is sensitive to the short‐range spin structure of the deuteron. However, the one‐nucleon exchange calculations using standard 3He and deuteron wave functions fail to reproduce the strong variation of the tensor analyzing powers as a function of angle in the cms. Sensitivity to relativistic effects is also discussed.

At the RCNP, there have been intensive experimental studies of few‐nucleon systems at intermediate energies in the last decade. A variety of spin observables have been measured as well as cross sections. By comparing data to rigorous calculations, the structure of three‐nucleon forces has been explored. In this talk, resent results and future perspectives are presented.

The structure of N—d low‐energy scattering states is described using the hyperspherical harmonics method with realistic Hamiltonian models, consisting of two‐ and three‐nucleon interactions. Both coordinate and momentum space two‐nucleon potential models are considered. Results for the zero‐energy N—d scattering lengths and for the p—d phase shift and mixing angle parameters at center‐of‐mass energy of 2 MeV are presented and discussed.

We review a novel, rigorous three‐body Coulomb treatment that incorporates the mesonic three‐body force and the excited‐nucleon three‐body force such as the Fujita‐Miyazawa type. Our method is mainly based on many‐potential theory and the coupled‐channels method. We clarify the difference between our theory and the approximate Coulomb treatment in the renormalization technique of Alt‐Sandhas‐Ziegelmann (ASZ), by examining the two‐body and three‐body equations term by term. Furthermore, we demonstrate why the ASZ method can numerically converge to a finite value regardless of its validity.

Measurements of analyzing powers Ay, Ayy, and Axx for d‐p elastic scattering were performed at Ed = 0.88 and 2.0 GeV using a high‐energy deuteron beam polarimeter at the Internal Target Station of the Nuclotron at JINR. The analyzing power data at 0.88 GeV are compared with several theoretical calculations.

The overbinding problem of Λ5He is solved by introducing a concept of coherent Λ‐Σ coupling which is equivalent to a ΛNN three‐body force. This three‐body force is coherently enhanced in the 0+ states of Λ4H and Λ4He. The 0+−1+ splitting in these hypernuclei is mainly due to coherent Λ‐Σ coupling and partly due to the ΛN spin‐spin interaction. A ΛNN three‐body potential is derived from the coupled‐channel treatment. The origin of the repulsive and attractive nature of the three‐body force is discussed. Coherent Λ‐Σ coupling becomes more important in neutron‐rich hypernuclei and especially in neutron‐star matter at high densities. The possible existence of “hyperheavy hydrogen”, Λ6H, is suggested.

We discuss the structure of 4He, Λ4H, Λ4He and ΛΛ4H. The calculated impulse approximation transition form factor 4He(e,e′)4He(02+) agrees with the available data. It is found that a major part of the energy‐weighted E0 sum rule value is exhausted by nonresonant, low‐energy continuum states other than the second 0+ state. Precise four‐body calculations have been performed for Λ4He and Λ4H taking explicitly into account the NNNΛ and NNNΣ channels and for ΛΛ4H with NNΛΛ and NNNΞ channels included. The role of ΛN‐ΣN coupling in Λ4He and Λ4H and the role of ΛΛ‐ΞN coupling in ΛΛ4H are important.

The three‐body nuclear force was calculated fifty years ago. This talk will describe how and why it was introduced and what the status of pion theory was at that time.

Results on three‐nucleon (3N) elastic scattering and breakup below the pion production threshold are discussed with emphasis on the need for a three‐nucleon force (3NF). The large discrepancies found between a theory based on numerical solutions of 3N Faddeev equations with modern NN potentials only and data point to the need for 3NF's. Successes and failures of the present 3NF models, mostly of a 2π‐exchange nature, to describe high precision 3N data are discussed. Effects due to relativity both in elastic nucleon‐deuteron (Nd) scattering and breakup reaction are presented and consequences for a 3NF study pointed out. As an application of 3N bound and scattering states, results for photodisintegration of 3N bound states are shown.

An equation of state (EOS) for uniform nuclear matter is constructed at zero and finite temperatures with the variational method starting from a realistic nuclear Hamiltonian composed of the AV18 two‐body potential and the UIX three‐nucleon interaction (TNI). The two‐body energy is calculated with a Jastrow wave function, and the TNI energy with the Fermi‐gas wave function. In this calculation, the Fujita‐Miyazawa (FM) 2π‐exchange term of the TNI energy is positive for symmetric nuclear matter. By taking into account the correlation between nucleons perturbatively, the expectation value of the FM term is modified to be negative in the low density region.

We study the effect of the tensor force on nuclear structure with mean‐field and beyond‐mean‐field methods. An important correlation induced by the tensor force is a two‐particle‐two‐hole (2p2h) correlation, which cannot be treated with a standard mean‐field method. To treat the 2p2h tensor correlation, we develop a new framework [charge‐ and parity‐projected Hartree‐Fock (CPPHF) method], which is a beyond‐mean‐field method. In the CPPHF method, we introduce single‐particle states with parity and charge mixing. The parity and charge projections are performed on a total wave function before variation. We apply the CPPHF method to oxygen isotopes including neutron‐rich ones. The potential energy from the tensor force has the same order of magnitude as that from the LS force and becomes smaller with neutron number, which indicates that excess neutrons do not contribute to the 2p2h tensor correlation significantly. We also study the effect of the tensor force on spin‐orbit‐splitting (ls‐splitting) in a neutro...

In this paper, we briefly review some aspects of the gravitational many‐body problem, which is one of the oldest problems in the modern mathematical science. Then we review our GRAPE project to design computers specialized to this problem.

We describe a few‐body calculation of ΛΛ5H as well as ΛΛ4H and ΛΛ6He taking account fully coupled‐channel two‐baryon potentials acting among the octet of baryons. The wave function includes not only pnnΛΛ and ppnnΞ− components but also pnnΛΣ0, ppnΛΣ−, pnnΣ0Σ0 and ppnΣ0Σ−. An effective YY potential based on Nijmegen model D is used. We find that the pnnλΣ0 and ppnΛΣ− components play an important role in producing the ΛΛ5H bound state. The present result requires the introduction of a new coupled‐channel three‐body‐force, NΛΛ—NNΞ, if the intermediate pnnλσ0 and ppnΛΣ− states are eliminated from the model space.

The history of the three‐nucleon analyzing power puzzle is described from the point of view of an experimentalist who has been collaborating closely with few‐body theoreticians in trying to unravel the physics behind this long‐standing low‐energy scattering phenomenon. Although a number of very interesting and surprising effects have been found along the way, the puzzle is still unexplained. Currently, the hope is that long‐range three‐nucleon force terms predicted by Chiral Effective Field Theory in N3LO will eventually solve the puzzle.

There are so‐called Borromean nuclei on the drip‐line in the nuclear chart, where any two‐body subsystem has no bound state. The exotic structure and responses of Borromean nuclei have been studied by measurements of three‐body (final‐state) channels produced via direct reactions. Measurement of the three‐body decay of the isospin partner of light drip‐line nuclei populated by the charge exchange reaction is discussed as a means for studying the neutron halo structure. Experimental efforts to study nuclei beyond the drip‐line, where many‐body resonances may appear, are also presented.

Recently it was found that the differential cross sections of elastic Nd scattering below 150 MeV can be well reproduced by incorporating a 3NF in Faddeev calculations based on modern nucleon‐nucleon (NN) interactions. On the other hand, the differential cross sections for nd and pd at 250 MeV show large discrepancies between the data and the Faddeev calculations with a 3NF. This indicates the existence of the missing features of the three nucleon force in this energy region. For the next step in the 3NF study, we have measured the vector analyzing power Ay and the differential cross sections for the 2H(p,pp)n breakup reaction at 250 MeV. The experiment was carried out by detecting two protons in the final state with using the double‐armed spectrometer Grand Raiden (GR) and the Large Acceptance Spectrometer (LAS) at the Research Center for Nuclear Physics (RCNP). The data was compared with the results of Faddeev calculations with and without a 3NF.

Ab‐initio calculations of light nuclei require three‐nucleon potentials in addition to realistic two‐nucleon forces to obtain the empirical binding energies. The current status of the Illinois three‐nucleon potentials used with Argonne v18 is presented.

The ΛNN three‐body force, through ΛN‐ΣN coupling, plays an important role in the structure of Λ hypernuclei. We have been studying the ΛN interaction via hypernuclear γ‐ray spectroscopy experiments and obtained the effective interaction strengths of the spin‐dependent ΛN interactions. In addition, a possible effect of the ΛNN three‐body force is being investigated from precise level schemes of light Λ hypernuclei. The ΛNN three‐body force can also be studied from the structure of neutron‐rich Λ hypernuclei by using the (π−,K+) reaction.

Previously we calculated the binding energies of the triton and hypertriton, using an SU6 quark‐model interaction which is obtained by a resonating‐group method for two baryon clusters. In contrast to the previous calculations employing the energy‐dependent interaction kernel, we present new results using a renormalized interaction which is energy‐independent and still preserves all the two‐baryon data. The new binding energies are slightly smaller than the previous values. In particular the triton binding energy turns out to be 8.14 MeV with a charge‐dependence correction of the two‐nucleon force, 190 keV, being included. This indicates that the energy to be accounted for by three‐body forces is about 350 keV.

A phenomenological three‐nucleon force is introduced to get rid of discrepancies between experimental data and calculations with a realistic nucleon‐nucleon force plus the two‐pion exchange three‐nucleon force in low‐energy three‐nucleon scattering observables. Effects of this force, which consists of scalar, vector, and tensor components in spin space, on observables at higher energies are examined.

Inclusive experiments for D(p,p)pn breakup were performed at incident proton energies of 247 MeV and 13 MeV. At 247 MeV, the cross sections and analyzing power Ay measured at angles from 7 ° to 20 ° largely disagree with calculations even if a 2π‐exchange three‐nucleon force (2π3NF) effects are included, and the disagreement increases at forward angles. At 13 MeV, cross section measured at angles from 10 ° to 70 ° agrees well with pd calculation and 2π3NF effects are small. The large disagreement in pd breakup at 247 MeV may have some relationship with disagreements in pd scattering at 250 MeV.

Three-nucleon interactions are a frontier in understanding and predicting the structure of strongly-interacting matter in laboratory nuclei and in the cosmos. We present results and discuss the status of first calculations with microscopic three-nucleon interactions beyond light nuclei. This coherent effort is possible due to advances based on effective field theory and renormalization group methods in nuclear physics., 7 pages, 11 figures, talk at International Symposium on New Facet of Three-Nucleon Force (FM50), Tokyo, October, 2007

We report on an ab initio calculation of the 4He total photo‐absorption cross section using two‐ and three‐nucleon interactions based upon chiral effective field theory. The microscopic treatment of the continuum problem is achieved using the Lorentz integral transform method, applied within the no‐core shell model approach.

Recent progress on the solution of ab initio three‐ and four‐nucleon scattering equations in momentum space that include the correct treatment of the Coulomb interaction is reviewed; results for specific observables in reactions initiated by p+d, p+3He and n+3He indicate that the inclusion of the Coulomb interaction is paramount to validate two‐ and three‐nucleon force models. Three‐ and four‐nucleon force effects in 4He binding energy and four‐nucleon scattering observables are studied for the first time. The effect of the four‐nucleon force is found to be much smaller than the effect of the three‐nucleon force.

In commemoration of the 50 years anniversary of Fujita‐Miyaszawa theory on the 3‐body interaction among nucleons, we would like to review on the phenomena inherent to many‐body interactions in condensed matters: (1) 3‐body non‐additive interaction among atoms which causes significant effect on the third order virial coefficient, (2) the many‐body (ring) exchange in the solid helium 3 which plays important role, and (3) effective long range interaction induced by the elastic interaction in spin‐crossover materials which causes a peculiar phase transition of the mean‐field universality class.

I discuss the Fujita‐Miyazawa three‐nucleon force in the light of chiral effective field theory.

The 3‐nucleon force at N3LO in chiral effective field theory is briefly reviewed. The two‐pion‐one‐pion‐exchange 3‐nucleon force is decomposed into partial waves.

Recent progress in our three nucleon force study with three nucleon scattering at intermediate energies (E/A≈100 MeV) is presented, especially focusing on experimental deuteron‐proton elastic scattering and breakup reactions at RIKEN. One signature of three nucleon forces is identified in the cross section minimum for deuteron‐proton elastic scattering by direct comparison between precision data and state‐of‐the‐art Faddeev calculations based on realistic nucleon‐nucleon forces plus 2π‐exchange three nucleon forces. However, the polarization observables are not always well described by adding the model three nucleon forces, indicating that components other than a 2π‐exchange three nucleon force are required to describe the data.

We suggest that the Fujita‐Miyazawa force plays a crucial role in determining the neutron drip line for the oxygen isotopes. This is one of the consequences of the repulsive effective T = 1 force produced by the Fujita‐Miyazama mechanism. The same mechanism makes the effective T = 1 interaction more repulsive in general.

Cluster‐cluster local potentials reproducing the phase shifts of binary systems are usually adopted to describe few cluster sytems for their simplicity, but it turns out that the nonlocal nature of these composite clusters is something that we cannot discard.