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1.
Differential cross sections and vector analyzing powers of deuteron elastic and inelastic scattering have been measured at 56 MeV over the whole range of the even samarium isotopes. Comprehensive analyses were performed with the optical model and the coupled-channels formalism. In the optical model analysis, calculations with a global parameter set could reproduce the experimental data only for the vibrational nuclei. The strong coupling approximation was applied assuming the 144, 148, 150Sm to be harmonic vibrators and the 152,154Sm symmetric rotators. The 2λ (λ = 2, 3, 4, 6) pole deformation parameters were deduced from a systematic coupled-channels analysis. The transition strengths were extracted from the deformed optical potentials and compared with the corresponding electromagnetic ones. The transition rates for the rotational nuclei agreed with the electro-magnetic ones, but those for the vibrational nuclei gave the systematically smaller values. The latter fact was attributed to the difference between the proton and neutron transition matrix elements near the neutron-closed-shell nuclei. The ratios of the two matrix elements were obtained.  相似文献   

2.
Cross sections and analyzing powers have been measured for elastic and inelastic scattering of 15 MeV deuterons from 148'Sm and 152Sm. These data, as well as previous data for the 48, 50Ti(d, d') reaction have been analyzed in the coupled-channels approximation. Data for 48Ti and 152Sm are better described by the rotational model than by the vibrational model but the quality of the fits is not sufficiently good to establish (d, d') reactions as a sensitive method of discriminating between these two models.  相似文献   

3.
The elastic and inelastic scattering of 11.8 MeV vector polarized deuterons from 34S has been studied. Angular distributions of the cross section σ(θ) and vector analyzing power iT11(θ) have been measured for the ground state and the first three excited states in 34S. Optical model parameters were first obtained by fitting the elastic deuteron scattering data alone. DWBA calculations with a collective model form factor were performed for the inelastic scattering to the excited states. Coupled-channels calculations were also done both for the one-phonon and the two-phonon excited states. The optical model parameters were suitably modified to obtain simultaneous fit to elastic and inelastic data when channel coupling was introduced. The values of the vibrational parameter β2 for one- and two-phonon states are discussed and compared with those obtained from γ-decay width studies.  相似文献   

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Polarization parameters have been determined for deuteron elastic scattering from 27Al, Si and 60Ni at energies between 7 and 11 MeV and laboratory scattering angles from 30° to 135°. The vector polarization, iT11, and two tensor parameters T20 and T22, were measured by scattering polarized and unpolarized deuterons which were obtained from a tandem accelerator. The largest polarization was |iT11| ≈ 0.3 and |T20| ≈ 0.2 for 27Al at 11 MeV. For 60Ni, the observed polarizations were substantially smaller. Angular distributions of the unpolarized cross section were also measured for 27Al and Si. An optical-model analysis of the polarization and cross-section data was performed. The vector polarization was reproduced reasonably well by a vector spin-orbit coupling of similar strength as found for nucleon scattering. A tensor interaction appears to be needed to account for the observed tensor polarizations.  相似文献   

6.
The differential cross section and the vector and tensor analyzing powers Ay, Axx, Ayy and Axz were measured for the d-4He elastic scattering at 56 MeV. The measurement of Axz was performed using a deuteron beam polarized in the horizontal plane. An optical-model analysis of the experimental data was carried out. The magnitude of the tensor analyzing powers could not be reproduced without the tensor potential. By including the TR type tensor potential, the optical-model calculations give a reasonable reproduction of the experimental data at θc.m. < 120°. The obtained TR tensor potential was much stronger than that predicted by the folding model. The strength of the real TR potential was roughly in accordance with that obtained from the optical-model analysis of d-4He elastic scattering at 20.2 MeV.  相似文献   

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Elastic electron scattering on 90Zr and 92Mo has been measured at 200 and 300 MeV up to 2 fm−1 momentum transfer. Data analysis led us to adopt the parabolic Gaussian shape as a valuable charge distribution for these nuclei. For 90Zr, we have compared this model with charge distributions given by recent Hartree-Fock calculations.  相似文献   

12.
Angular distributions of differential cross sections and analysing powers have been measured for elastic and inelastic scattering of polarized 33 MeV 3He from 17O, 18O, 54Fe and 56Fe targets. The elastic data have been analysed to deduce the optical model parameters. The inelastic scattering together with the elastic scattering have been interpreted in terms of a macroscopic model within a coupled-channels framework. From this analysis the deformation parameters, β, were deduced.  相似文献   

13.
The elastic scattering of 79.5 MeV 11B ions has been studied for seven targets ranging in mass from 24Mg to 197Au and of 87.5 MeV 10B ions for three of these targets (24, 25Mg, 60Ni). Angular distributions were measured from ~10° c.m. in steps of 0.5°, to angles beyond 40° c.m. where the elastic cross sections are ? 10?3 of the Rutherford values (except for 197Au). Inelastic data for exciting the lowest 2+ states of 24,26Mg and 60Ni were also obtained. Important odd-A-even-A differences are observed in the 11B elastic angular distributions for the Mg and Al targets; for 10B scattering these are obscured by projectile quadrupole moment effects on the elastic scattering. The elastic data were analyzed using the optical model with potentials of both Woods-Saxon and double-folding form. The data for both 10B and 11B are consistent with the potential obtained in the folding model with the M3Y interaction without renormalization. The inelastic data were analyzed by the distorted-waves method.  相似文献   

14.
Angular distributions of π+ and π? at 100 MeV incident energy were measured for elastic and inelastic scattering from 12C and 13C. Elastic data were obtained between 6° and 180°. Inelastic scattering on the 2+ (4.4 MeV), 0+ (7.6 MeV), 3? (9.6 MeV) and 1+ (12.7 MeV) states of 12C and on the 32? (3.7 MeV), 52? (7.5 MeV), 92+ (9.5 MeV) and 11.7 MeV states of 13C was mea 12C results are compared to a Δ-hole model.  相似文献   

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The elastic scattering of 88 MeV 6Li ions has been studied for eleven targets ranging in mass from 24Mg to 208Pb. Angular distributions were measured from about 10° c.m. in steps of 0.5°, mostly out to 60 or 70° c.m. where the elastic cross sections range from 10?3 to 10?5 of the Rutherford values. Inelastic data for exciting the lowest 2+ states of 24,26Mg and 60Ni were also obtained. The elastic data were analyzed using the optical model, with potentials of both Woods-Saxon and double-folding forms. The analysis confirms that the potentials for 6Li obtained from the folding model with the M3Y interaction need renormalizing by about 0.6, in agreement with results obtained at other energies. The inelastic data were compared to distorted-wave calculations. Coupled-channels analyses were also made for 24, 26Mg, 60Ni and 59Co. Reorientation effects were found to be important to give the correct 2+ angular distributions for 24, 26Mg and could also account for the differences between the elastic scattering from the odd-A and adjacent even-A targets.  相似文献   

17.
Excitation curves for the elastic and the inelastic scattering of polarized protons on the target nuclei 138Ba, 140Ce, 142Nd and 144Sm have been measured in the energy region of prominent isobaric analog resonances. A detailed analysis of the data is presented. Definite Jπ assignments are given for a number of parent analog states. Spectroscopic factors and amplitudes for configurations with the core in the ground state or in the 21+ excited state are derived from the elastic and inelastic proton decay amplitudes. They show consistency with sum rules including orthogonality conditions. Different methods for the-calculation of single particle decay widths have been applied. The qualitative agreement with present unified model calculations is remarkable; an overestimattion of the weak coupling structure, however, becomes apparent.  相似文献   

18.
Differential cross sections were measured at 8, 10, 12 and 14 MeV for elastic scattering of neutrons from enriched samples of 54Fe, 56Fe, 63Cu and 65Cu. Inelastic scattering to the first excited state in 54, 56Fe was also observed. For the 63, 65Cu isotopes, the inelastic cross sections for scattering to the combined group of the three (five) states were determined at 8 and 10 MeV (12 and 14 MeV). The elastic scattering data are compared to predictions of earlier global optical models. New spherical optical model representations were obtained. These data were combined with data for nickel, tin and lead to generate a new global parametrization. Comparisons of derived volume integrals for the potentials, total cross sections and potential radii are made to available information.  相似文献   

19.
Measurements for the elastic and inelastic scattering of 500 MeV protons from 40Ca and 208Pb at small momentum transfers are reported. The induced proton polarization P and the spin rotation parameter Q were measured for the elastic scattering. The spin rotation parameters DSS, DSL, DLL, dLS and the induced polarization P were measured for transitions to the 3(3.37 MeV) and 5(4.48 MeV) states in 40Ca and the 3(2.61 MeV) state in 208Pb. Comparisons of the data with the theoretical calculations were carried out in the framework of nonrelativistic and relativistic approaches. We extracted the spin-up and spin-down channels for the elastic scattering cross sections and found that predictions of the relativistic and nonrelativistic approaches agree well with the spin-up channel data and differ considerably in the spin-down channel.  相似文献   

20.
The parity violating asymmetry is calculated for polarized electron-deuteron inelastic scattering in the closure approximation for the outgoing nucleons. The results are applicable in the intermediate-energy region of the incident electron where asymmetries are found to be in the range accessible to the present experiments.  相似文献   

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