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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]

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. [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]

A method of model-independent spin-parity determination is proposed for the (d, 2He) reaction by using the tensor analyzing power Azz at θ = 0°, which shows extreme values for 0- and natural-parity states solely by parity-conservation. It is applied to the 12C(d, 2He)12B reaction at Ed = 270 MeV and a possible indication of 0- state is found at Ex = 9.3 MeV in 12B. The bump at Ex = 7.5 MeV appears to have more 2- strength than 1- strength, consistent with our earlier work. © 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]

Single and double spin-flip probabilities in inelastic deuteron scattering on 12C have been measured at 270 MeV up to 50 MeV in excitation energy using a focal plane deuteron polarimeter capable of measuring both vector and tensor components of the deuteron polarization. The obtained S1 values are enhanced relative to the Fermi gas model prediction in highly excited continuum region. The S2 values are close to zero over the measured excitation energy range. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Precise measurements of the deuteron to proton polarization transfer coefficients for the d-p elastic scattering has been made at 135 MeV/u at RIKEN Accelerator Research Facility. The obtained results are compared with the Faddeev calculations based on modern nucleon-nucleon forces together with Tucson-Melbourne, Tucson-Melbourne′ and Urbana-Argonne type of three nucleon forces. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Measurements of the tensor and vector analyzing powers Ayy, Axx, Axz, and Ay for the dvector d → 3Hen and dvector d → 3Hp reactions were performed at Ed = 270 and 200 MeV over wide angular range. T20 at θcm = 0° and 180° were also measured at Ed = 270, 200, and 140 MeV. Obtained data were compared with predictions based on one nucleon exchange approximation. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Capillary discharge experiments were carried out to get a lasing of Ne-like Ar. The relation between the appearance of the laser output and the instabilities of longitudinal modes has been studied by side-view observation. And observation of lasing at a low discharge current of 9 kA provides us a possibility of designing a compact and high-repetition-rate soft X-ray laser by use of a semiconductor switch instead of a gap switch. [ABSTRACT FROM AUTHOR]

It is known that the irreversibility field depends largely on the electric field criterion, E[sub c], for the determination of the critical current density. In addition, it was recently found that the vortex glass-liquid transition field determined by the scaling of current-voltage curves also depended on the range of electric field in the measurement. In this paper the two characteristic fields are measured for a Bi-2223 silver-sheathed tape as a function of the electric field. The obtained result of the irreversibility field is compared with the theoretical result of the flux creep-flow model. Based on the agreement with the theoretical model a standard test method of the irreversibility field is proposed. [ABSTRACT FROM AUTHOR]

Precise data on cross sections, analyzing powers and polarization transfer coefficients are measured for the dp elastic scattering at 270 MeV (135 MeV/nucleon) and compared to Faddeev calculations assuming the nd scattering with modern nucleon-nucleon (NN) forces including the 2π exchange Tucson-Melbourne (TM) three-nucleon (3N) force. Excellent fits are obtained for the cross sections and vector analyzing powers when the 3N force is included, while the fits are deteriorated for the tensor analyzing powers if the 3N force is included. A moderate fit is obtained for the polarization transfer coefficients. Based on theses results, one can conclude that the size of amplitudes of the TM-3N force may be adequate but the spin dependent part may be deficient. The cross sections and the vector analyzing powers for the nd elastic scattering at 250 MeV are measured for the first time. Backward cross sections are underestimated by the NN+3N force Faddeev calculations. This difference might be attributed to relativistic effects. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Experimental results are presented for the first time on the deformation of thin aluminum foils induced by 8MeV Si[sup 4+] ions irradiation. The deformation was measured systematically using a laser displacement meter with accuracy of 0.1 µm, as a function of the incident beam current ranging from 1 to 200 nA for two different foil thickness of 2 and 5 µm foils. Protrusive deformation profile was observed only within the beam spot size. The deformation was found to be completely elastic without hysteresis and was independent of the beam current. The deformation was increases linearly as the beam current increases up to 10 nA, above which it increases more rapidly. The surface expansion for a given foil is saturated at some beam current. The present method will be developed as a new method to study ion-solid interaction relating to high-density electronic excitation, thermal deformation of thin foil and ion track structure. [ABSTRACT FROM AUTHOR]

We report measurements of the deuteron single and double spin-flip probabilities (SFPs), S[sub 1] and S[sub 2], for the (↘, ↘') reaction on [sup 12]C and [sup 28]Si at 270 MeV over an excitation energy range of 4-24 MeV and a scattering angular range of 2.5-7.5°. The SFP S[sub 1] exhibits large positive values for known spin-flip states, while it has values close to zero for non-spin-flip states. The SFP S[sub 2] is close to zero for all the measured excitation energy region. The results for the 1[sup +] (12.71 MeV) and 2[sup +] (4.44 MeV) states in [sup 12]C are well described by the microscopic DWIA calculations. The deuteron SFPs provide signatures of isoscalar single and double spin-flip nuclear excitations. [ABSTRACT FROM AUTHOR]

Polarization observables for the ³He(↘, p)[sup 4]He reaction have been measured at E[sub d] =140, 200, and 270 MeV. This work aims to investigate the high momentum component of deuteron D-state wave function and the mechanism for the one-nucleon transfer reaction at intermediate energies. Data are compared with impulse approximation calculation based on the three-nucleon scattering amplitudes. [ABSTRACT FROM AUTHOR]

Precise measurements of the cross sections and deuteron analyzing powers (A[sub y], A[sub yy], A[sub xx] and A[sub xz]) for the d-p elastic scattering has been made at E[sub d] = 140, 200 and 270 MeV at RIKEN Accelerator Research Facility. The obtained results are compared with the Faddeev calculations based on modern nucleon-nucleon forces together with Tucson-Melbourne type and Urbana-Argonne type of three nucleon forces. [ABSTRACT FROM AUTHOR]

We have calibrated the effective analyzing powers of the deuteron polarimeter, DPOL, in the deuteron energy region of 210 < E[sub d] < 270 MeV. The calibration was needed to analyze the polarization transfer measurement for the [sup 12]C(↘, ↘') reaction at 270 McV whose aim is to search for Double Gamow-Teller resonances in [sup 12]C in an excitation energy region of E[sub x] < 60 MeV. [ABSTRACT FROM AUTHOR]

The [sup 12]C(↘, α)[sup 10]B*(2[sup +]) reaction at 0° is proposed as a new standard for the deuteron beam polarization at an intermediate energy region. The absolute value of the polarization is measured using this reaction at 270 and 140 MeV deuteron energies for the first time. The obtained beam polarization is used for the calibration of the analyzing powers for the ↘-p elastic scattering which we use as a polarimetry. The result is almost consistent with the data of the previous calibrations. [ABSTRACT FROM AUTHOR]

Construction of the RIKEN Intermediate-stage Ring Cyclotron (IRC) started in 1998. Four sector magnets are completed. Magnetic field measurement of the sector magnet is in progress. Two main resonators are assembled. Fine adjustments of the resonators are going on. Almost all the other components are also completed. [ABSTRACT FROM AUTHOR]

An (n,p) facility has been constructed at the Research Center for Nuclear Physics. The polarized neutron beam, produced by the [sup 7]Li(&prarr;, n) reaction, bombards the (n, p) targets placed in the multi-wire drift chamber (MWDC) box. The scattering position is detected by the MWDC and the momentum of the outgoing proton is analyzed by the Large Acceptance Spectrometer (see K. Yako et al. in RCNP annual report 1999). A commissioning run has been performed by using the np scattering. About 2 x 10[sup 6]/sec neutrons were produced in the target area of 20[sup H] x 30[sup W] (mm²). The typical n-beam polarization was 0.15. The energy resolution of the measurement was 1.4 MeV and the measured differential cross sections are consistent with the known values. By using this facility, the measurement for the [sup 90]Zr(n,p)[sup 90]Y reaction at 300 MeV has been carried out as well as the nd elastic scattering measurement at 250 MeV. [ABSTRACT FROM AUTHOR]

Polarization transfer measurements at forward angles have been used to detect and extract strengths of spin-dependent excitations in nuclei. It was recently demonstrated experimentally and proved theoretically that a rotationally invariant quantity constructed from the polarization transfer coefficients for nucleon-nucleus scattering takes a unique value at 0° for unnatural parity transitions. For natural parity transitions the value of the invariant provides a measure of the spin-flip mixture in the transition. The present contribution extends the above result to general inclusive nuclear reactions A(a, b)B with arbitrary projectile/ejectile spins and target excitations. The result gives a relation between the set of invariant values and that of the target spin-flip transition strengths. [ABSTRACT FROM AUTHOR]

We recently created a snake depolarizing resonance using an rf solenoid magnet in a ring containing a nearly 100% Siberian snake. We found that the primary snake rf resonance also had two weaker synchrotron sidebands, which are second-order snake resonances; they were probably caused by the energy-dependent strength of the solenoid snake due to the Lorentz contraction of its longitudinal ∫ B · dl. This was the first observation of an rf synchrotron-sideband depolarizing resonance in the presence of a nearly full Siberian snake. [ABSTRACT FROM AUTHOR]