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The primordial nucleosynthesis(BBN) right after the big bang (BB) is one of the key elements that basically support the BB model. The BBN is well known that it produced primarily light elements, and explains reasonably most of the elemental abundances. However, there remains an interesting and serious question. That is so called the cosmological 7Li problem in BBN. The BBN simulations using nuclear data together with the recent detailed micro-wave background measurements explain most of the light elements including D, 4He, etc, but the 7Li abundance is over predicted roughly by a factor of three. Although this problem should be investigated in all the fields relevant including physics and astronomical observations, I will concentrate my discussion on the nuclear physics side, especially the recent progress for studying the last possible major destruction process of 7Be, the 7Be(n,α)4He reaction, which would reduce the overproduction if the cross section is large. There are several efforts recently made for the 7Be(n,α)4He reaction in the world. A new theoretical estimate was made compiling all available data of the mirror reaction 7Li(p,α)4He, suggesting about one order smaller reaction rate than the ones currently being used (Wagoner rate). The n-TOF group measured some part of the s-wave components of the reaction, suggesting that the s-wave contributions are much smaller than the Wagoner rate. The p-wave component was measured clearly at RCNP, Osaka using the time-reverse reaction 4He(α,n)7Be, indicating that the p-wave contribution dominates at the effective temperature region for the BBN. However, the sum of the s-wave and p-wave contributions is about one order of magnitude smaller than the Wagoner rate. It should be of great interest to confirm by the indirect method, Trojan-Horse method to deduce cross sections at the effective temperature region, and also see the cross sections for a wider energy range systematically, which is under way by the BELICOS project by Livio Lamia and by the CRIB collaboration lead by S. Hayakawa. [ABSTRACT FROM AUTHOR]

Recently, we reported a fullerene modification using neutral-neutral or neutral-ion collision reactions in the two-chamber configuration of the Bio-Nano electron cyclotron resonance ion source (ECRIS). In our methodology, modified fullerenes can be synthesized in vapor-phase in an ECR plasma, or on a surface of a plasma chamber, and can be characterized by on-line mass spectrometric analysis of the ECRIS beam, or by off-line analyses (e.g. time-of-flight mass spectrometry, liquid chromatography mass spectrometry, etc.). So far, we have successfully synthesized a modified C70 with iron (Fe) and chlorine (Cl) atoms using two individual plasmas; Fe-Cl plasma and C70 plasma. In a subsequent experiment, shown in this study, we investigated the ion/electron density distributions in the plasma chamber by using electrostatic probe method. We correlated these results with the off-line synthesized material investigations and also with plasma electron simulations in order to collect more information on the mechanism of the synthesis process. [ABSTRACT FROM AUTHOR]

Electric dipole (E1) reduced transition probability B(E1) of 90Zr was obtained by the inelastic proton scattering near 0 degrees using a 295 MeV proton beam and multipole decomposition analysis of the angular distribution by the distorted-wave Born approximation with the Hartree-Fock plus random-phase approximation model and inclusion of E1 Coulomb excitation, and the E1 strength of the pygmy dipole resonance was found in the vicinity of the neutron threshold in the low-energy tail of the giant dipole resonance. Using the data, we plan to determine the precise dipole polarizability aD which is defined as an inversely energy-weighted sum value of the elecrric dipole strength. The dipole polarizability is expected to constrain the symmetry energy term of the neutron matter equation of state. Thus systematical measurement of the dipole polarizability is important. [ABSTRACT FROM AUTHOR]

Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the α resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of 7Be+α resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the 7Be(α, ã ) reaction, and proposed a new cluster band in 11C. [ABSTRACT FROM AUTHOR]

The reduced transition probability B(E2;0+gs→2+1) for the proton-rich nucleus 28S was determined experimentally using intermediate-energy Coulomb excitation. The resultant B(E2) value 181(31) e2fm4 is smaller than those of neighboring N = 12 isotones and Z = 16 isotopes. The double ratio |Mn/Mp|/(N/Z) of the 0+gs→2+1 transition in 28S was obtained to be 1.9(2) by evaluating the Mn value from the known B(E2) value of the mirror nucleus 28Mg, showing the hindrance of proton collectivity relative to that of neutrons. These results indicate the emergence of the magic number Z = 16 in 28S. [ABSTRACT FROM AUTHOR]

The alpha inelastic scattering from 24Mg was measured to obtain the isoscalar natural-parity excitation strengths and to search for the α-condensed states. The multipole decomposition analysis for the measured cross sections was performed. The strength distributions for the ΔL = 0-3 were successfully obtained and the possible candidates for the α-condensed states around the 16O core were found. [ABSTRACT FROM AUTHOR]

We performed a 37Cl(3He, t)37Ar experiment at E = 140 MeV/nucleon and 0° with a resolution of 30 keV. The Gamow-Teller (GT) strength distribution was obtained up to the excitation energy (Ex) of 14.2 MeV in 37Ar. Under the assumption of isospin symmetry, the GT strengths in the 37Cl→37Ar and 37Ca→37K transitions are analogous. The obtained strength distribution was compared with the mirror 37Ca β decay up to Ex = 8.6 MeV. The overall shapes of the distributions were similar, but the details were not necessary the same. In order to understand those differences, the experimental distribution was compared with the shell model (SM) calculation using the USD interaction. The SM calculation suggests that differences at lower energies can be caused by a large tensor contribution in the charge-exchange reaction. On the other hand, the differences seen at higher energies are due to the breaking of the mirror symmetry. The neutrino cross section for the 8B solar neutrino source was calculated using the obtained data. [ABSTRACT FROM AUTHOR]

The cluster structures of the excited states in 11B and 13C were discussed by measuring the isoscalar monopole strengths in the inelastic α scattering at Eα = 388 MeV. It was found that the 1/22-, 1/23-, and 1/24- states in 13C are candidates for the α cluster states with a 3α+n molecular configuration. [ABSTRACT FROM AUTHOR]

The high-resolution SHARAQ spectrometer and the dedicated high-resolution beam-line have been constructed at the RI beam factory and commissioned in 2009. Multi-wire drift chambers placed in the beam-line and cathode read-out drift chambers placed at the SHARAQ focal plane worked well for heavy ion beams with Z=1–7 at 200–300 MeV/nucleon. By introducing a dispersion matched operation of the beam-line, we have achieved a momentum resolution of δp/p = 1/8100 for a primary beam of 14N beam with a momentum spread of ±0.1%. Experiments by use of novel RI-beam induced charge exchange reactions are planned. [ABSTRACT FROM AUTHOR]

The high-resolution SHARAQ spectrometer and the dedicated high-resolution beamline have been constructed at RI beam factory and commissioned in 2009. Lateral and angular dispersion matching conditions were achieved simultaneously for a primay beam with a momentum spread of 0.1% and an emittance of 3π mm·mrad (σ). An overview of the spectrometer and the beam-line, preliminary results from the commissioning runs, and future experimental plan with the system are described. [ABSTRACT FROM AUTHOR]

The double differential cross sections for the 116Cd(p,n) and 116Sn(n,p) reactions at 300 MeV have been measured over a wide excitation-energy region including Gamow-Teller (GT) giant resonance (GTGR) for studying GT transition strengths in the intermediate nucleus of the 116Cd double-β decay, namely 116In. A large amount of the strengths in the β+ direction has been newly found in the energy region up to 30 MeV, which may imply that the GT strengths in the GTGR region contribute to the nuclear matrix element of the two-neutrino double-β decay. [ABSTRACT FROM AUTHOR]

The structure of electric and magnetic dipole modes in 208Pb is investigated in a high-resolution measurement of the (vector p,vector p′) reaction under 0°. First results on the E1 strength in the region of the pygmy dipole resonance are reported. [ABSTRACT FROM AUTHOR]

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(pvector ,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. [ABSTRACT FROM AUTHOR]

A new type of the spin polarized solid proton target has been constructed which can be operated under a low magnetic field of 0.08 T and a high temperature of 100 K. First polarization asymmetry measurement with an unstable beam of 6He with an energy of 71 MeV/u has been successfully carried out. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The cross sections and analyzing powers of the 16O(p,p′)16O(0-,T = 1) scattering were measured at a bombarding energy of 295 MeV and an angular range of 14° ≤ θlab ≤ 30°. The isovector 0- state at Ex = 12.80 MeV is clearly separated from the neighboring states with an energy resolution of ΔE ≃ 30 keV. The data have been compared with distorted wave impulse approximation (DWIA) calculations. The analyzing powers are sensitve to the effective nucleon-nucleon (NN) interaction used in DWIA calculations, and our data support the medium modification of the NN interaction in nuclei. The DWIA calculation employing a random phase approximation (RPA) response function predicts an enhancement of the cross sections around a momentum transfer of q ≃ 1.7 fm-1, and it gives a reasonable agreement with the data. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

The cross sections and analyzing powers were measured for 3He+12C, 58Ni, and 90Zr elastic scattering at T3He=450 MeV. The incident energy dependence of the volume integral per nucleon for 3He shows the similar behavior to that of protons if the spin-orbit potential is taken into account. This result supports the assumption that interactions between 3He and nucleus are dominated by the interactions between constituent nucleons of 3He and target nucleus in the intermediate energy region. The results of the single folding calculation suggest the interaction between point nucleon and target nucleus is modified in the 3He+nucleus elastic scattering. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Cross sections, analyzing powers and spin rotation parameters of proton elastic scattering from 58Ni and 120Sn have been measured at intermediate energies. Obtained data have been analyzed in the framework of relativistic impulse approximations. In order to explain the 58Ni data, it was necessary to modify NN interactions in the nuclear medium by changing coupling constants and masses of σ and ω mesons. For 120Sn, by assuming the same modification of NN interactions and by using proton densities deduced from charge densities, the neutron density distribution was searched so as to reproduce 120Sn data at 300 MeV. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Complete sets of observables in proton inelastic scattering from [sup 16]O have been measured at forward angles including 0°. Obtained spectra were decomposed into spin-flip and non spin-flip spectra by polarization transfer coefficients and spindipole strength spliting into several peaks was identified in the giant resonance region of E[sub x] = 19 ∼ 27 MeV in [sup 16]O. [ABSTRACT FROM AUTHOR]

Polarization transfer (PT) coefficients in the [sup 12]C, [sup 28]Si(p,p') reactions at a scattering angle of 0° are measured at E[sub p] = 392 MeV. The strength of the isoscalar central spin-dependent part (V[sub σ]) of the effective nucleon-nucleon interaction is studied by using the sensitivity of the PT coefficients for the excitation of the 1[sup +], T=0 state in [sup 12]C to the V[sub σ] strength. It is found that distorted wave impulse approximation (DWIA) calculations employing the Francy and Love effective interaction well reproduce the measured PT coefficients. [ABSTRACT FROM AUTHOR]

Cross sections, analyzing powers and spin rotation parameters of proton elastic scattering from [sup 58]Ni and [sup 120]Sn have been measured at intermediate energies. By elastic scattering off N=Z nuclei like [sup 58]Ni at intermediate energies we can study medium modification of the nucleon-nucleon (NN) interaction inside the nucleus, because proton distributions in target nuclei are constrained by charge distributions measured by electron scattering and neutron distributions can be assumed to be the same as proton’s. In order to explain our experimental data of [sup 58]Ni at large scattering angles, it was found to be necessary to use experimental densities deduced from charge densities measured by electron scattering and to modify the coupling constants and the masses of exchanged σ and ω mesons in the RIA, assuming linear dependencies of meson properties to nuclear densities. Parameters of the medium effect have been searched to reproduce the data. For N≠Z nuclei, neutron density distribution can be extracted from the elastic scattering, assuming the same medium modifications fixed by the [sup 58]Ni data and using proton distributions obtained from charge distributions. We have searched neutron density distributions obtained from charge distributions. We have searched neutron density distribution so as to reproduce [sup 120]Sn data at the proton incident energy of 300 MeV. Deduced neutron distribution has an increase at the nuclear center, which is consistent with the 3s[sub 1/2] orbit wave function as expected in [sup 120]Sn. At energies other than 300 MeV, experimental data of [sup 120]Sn have been also well reproduced by the neutron distribution obtained at 300 MeV. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

High-resolution measurements of proton inelastic and charge-exchange (³He,t) reactions at 0° on [sup 58]Ni were performed. These reactions mainly cause isovector spin flip transitions to M1 states in [sup 58]Ni and GT states in [sup 58]Cu. The "level-by-level" comparison of analogous M1 and GT transition strengths allows the study of the isospin symmetry structure of highly-excited analog states in [sup 58]Ni and [sup 58]Cu and identification of isospin T (T = 1 and 2) based on the different sensitivities of inelastic and charge exchange reactions. [ABSTRACT FROM AUTHOR]

We have constructed an experimental ensemble to measure polarization transfer observables in proton inelastic scattering at zero degrees. Excited states can simultaneously be measured for the excitation energy from 5 MeV to 35 MeV at E[sub p]=400 MeV. A fast data acquisition system has been developed to endure the large background event rate originated by the primary beam itself. We have found the effective analyzing power of the focal plane polarimeter slightly depends on the treatment of two-ray events. [ABSTRACT FROM AUTHOR]

Abstract. We present a new measurement of the energy dependence of nuclear transparency from AGS experiment E850, performed using the EVA solenoidal spectrometer, upgraded since 1995. Using a secondary beam from the AGS accelerator, we simultaneously measured pp elastic scattering from hydrogen and (p, 2p) quasi-elastic scattering in carbon at incoming momenta of 5.9, 8.0, 9.0, 11.7 and 14.4 GeV/c. This incident momentum range corresponds to a Q² region between 4.8 and 12.7 (GeV/c)². The detector allowed us to do a complete kinematic analysis for the center-of-mass polar angles in the range 85° - 90°. We report on the measured variation of the nuclear transparency with energy and compare the new results with previous measurements. [ABSTRACT FROM AUTHOR]

Abstract. We present an analysis of new data from Experiment E850 at BNL. We have characterized the inclusive cross section near the endpoint for pp cxclusive scattering in Hydrogen and in Carbon with incident beam energy of 6 GeV. We select events with a pair of back-to-back hadrons at large transverse momentum. These cross sections are parameterized with a form ... ~ (1 - X[sub L])[sup p], where X[sub L] is the ratio of the longitudinal momentum of the observed pair to the total incident beam momentum. Small value of p may suggest that the number of partons participating in the reaction is large and reaction has a strong dependence on the center-of-mass energy. We also discuss nuclear effects observed in our kinematic region. [ABSTRACT FROM AUTHOR]

Recently, a new technique for measuring short-range NN correlations in nuclei (NN SRCs) was reported by the E850 collaboration, using data from the EVA spectrometer at the AGS at Brookhaven National Laboratory In this talk, we will report on a larger set of data from new measurement by the collaboration, utilizing the same technique. This technique is based on a very simple kinematic approach. For quasielastic knockout of protons from a nucleus ([sup 12]C(p,2p) was used for the current work), we can reconstruct the momentum p[sub f] of the struck proton in the nucleus before the reaction, from the three momenta of the two detected protons, p[sub 1] and p[sub 2] and the three momentum of the incident proton, p[sub 0]:[DFORMULA]p[sub f]=p[sub 1]+p[sub 2]-p[sub 0][/DFORMULA] If there are significant n-p SRCs, then we would expect to find a neutron with momentum -p[sub f] in coincidence with the two protons, provided p[sub f] is larger than the Fermi momentum k[sub F] for the nucleus (∼220 MeV/c for [sup 12]C). Our results reported here confirm the earlier results from the E850 collaboration. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Abstract. Beams of protons and pions of 5.9 GeV/c were incident on a C target. Neutrons emitted into the back hemisphere, in the laboratory system, were detected in (triple) coincidence with two emerging Pt > 0.6 GeV/c particles. We present the momentum spectra of the backward going neutrons. We also integrated the spectra, and determined the fraction of the hard scattering events which are in coincidence with at least one neutron emitted into the back hemisphere, with momenta above 0.32 GeV/c. Contrary to the earlier measurements which found that only a small fraction (of the order of 10%) of the total inelastic cross section for light nuclei was associated with backward going nucleons, we find that about half of the events are of this nature. We speculate that the reason for the large difference is due to the strong dependence of the hard-scattering reaction upon the total center of mass energy (s) and short range nucleon correlations in nuclei. [ABSTRACT FROM AUTHOR]

Our experimental goal is to study the non-resonant triple alpha reaction rate at low temperature (T<108 K). The 13C(p,d) reaction at 66 MeV has been used to probe the alpha-unbound continuum state in 12C just below the 2nd 0+ state at 7.65 MeV. The transition strength to the continuum state is predicted to be sensitive to the non-resonant triple alpha reaction rate. The experiment has been performed at iThemba LABS. We report the present status of the experiment. [ABSTRACT FROM AUTHOR]

To test Bell’s inequality, measurements of spin correlations between two protons in the spin singlet state have been performed. Proton pairs in the singlet state were produced by the 1H(d,2He)n reaction at Ed = 270 MeV. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have designed and constructed a new beam line which can accomplish both lateral and angular dispersion matching with the Grand Raiden spectrometer. In dispersive mode, lateral and angular dispersions of the beam line are b[sub 16]=37.1 m and b[sub 26]=-20.0 rad, respectively, to satisfy matching conditions for Grand Raiden. In achromatic mode, the beam line satisfies the double achromatic condition of b[sub 16]=b[sub 26]=0. The magnifications of the beam line are (M[sub x], M[sub y]) = (-0.98, 0.89) and (-1.00,-0.99) for dispersive and achromatic modes, respectively. In the commissioning experiments, we have succeeded to separate the first excited 2[sup +] state of [sup 168]Er with E[sub x]=79.8 keV clearly from the ground state in the (p, p') reaction. We achieved energy resolutions of δE=13.0±0.3 keV and 16.7±0.3 kev in full width at half maximum for 295 MeV and 392 MeV protons, respectively. These energy resolutions agree with the resolving power of Grand Raiden for an object size of about 1 mm. [ABSTRACT FROM AUTHOR]

The [sup 12]C(↘, ²He)[sup 12]B measurement by Okamura et al. has shown that the spindipole resonance bump at E[sub χ] ... 7.5 MeV in [sup 12]B is most probably due mainly to the 2[sup -] states. This fact disagrees with the widely accepted assignment as 1[sup -]. Motivated by this work we studied the spin-parity of the mirror state located at E[sub χ] ... 7 MeV in [sup 12]N by measuring a complete set of polarization transfer (PT) coeffcients for the [sup 12]C(&prarr;, &brarr;)[sup 12]N reaction at 0°. We employed a 300 MeV polarized proton beam and the NTOF facility at the Research Center for Nuclear Physics. The PT coefficients enable us to disentangle the bump into spin-parity components as 1[sup -, sub δS=0] : 1[sup -, sub δS=1 = 0.08±0.02: 0.17±0.04: 0.75±0.04 in a plane-wave impulse approximation neglecting the contribution of the 0[sup -] states. This result clearly indicates that the dominant component of the bump is due to the 2[sup -] states and strongly supports the conclusion of Okamura et al. [ABSTRACT FROM AUTHOR]