首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
The polarization of 185 MeV protons in elastic scattering and in the excitation of the 2+ state at 4.44 MeV and the 0+ state at 7.65 MeV in 12C has been measured in the angular region 2°–60°. Optical model calculations are performed for the elastic scattering. Angular distributions for the inelastic scattering from the 2+ state at 4.44 MeV and the 3? state at 9.64 MeV are calculated in the distorted-wave impulse approximation (DWIA) as well as in the distorted-wave Born approximation (DWBA).  相似文献   

3.
4.
5.
The polarizations produced in the inelastic scattering of 185 MeV protons exciting the lowest octupole states in 12C and 208Pb are measured. The data together with earlier similar measurements for 40Ca and 90Zr are compared with existing theoretical models. The inclusion of a deformed spin-dependent interaction of the full Thomas form in the DWBA amplitude is found to considerably improve the theoretical fits to the data. For 12C, however, the DWBA fit is found to be inferior to that obtained using DWIA. The strong absorption model is found to give qualitatively good fits to the data for the heavier nuclei but again fails in the 12C case.  相似文献   

6.
The elastic and inelastic scattering of 178 MeV protons from 58Ni and 60Ni has been studied. Angular distributions were measured for the differential cross sections for elastic scattering as well as inelastic scattering from excited states below about 5 MeV, all with natural parity. For the elastic and for the inelastic scattering from the first excited state (2+ in both nuclei, the angular distributions for the polarization were also measured. The measurements extend out to c.m. angles of about 60°, corresponding to a momentum transfer of about 600 MeV/c.The elastic and inelastic scattering data were compared to the results of coupled-channel calculations in the vibrational model using a deformed spin-orbit interaction of the full Thomas form. Good agreement was found in general showing that the main features of the experimental results are well described in this model.  相似文献   

7.
Using a Ge(Li) total energy detector the elastic scattering of 100 MeV protons from 58Ni, 90Zr, 120Sn and 208Pb has been measured. Optical model fits with x2N of order unity have been made. The parameters of these fits varied systematically with A enabling the isospin dependence of the real part of the potential and its volume integral to be deduced. The limitations of the conventional optical model analysis in the case of 58Ni are illustrated and discussed.  相似文献   

8.
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   

9.
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   

10.
The differential cross section for elastic scattering of protons from the 9Li nucleus has been calculated within the framework of the Glauber multiple scattering theory. The calculations were carried out with two versions of cluster wave functions for the nucleus obtained within the α-t-2n and 7Li-n-n three-body models with realistic potentials of intercluster interactions. The differential cross section was calculated at E = 700 and 60 MeV/nucleon. A comparison with the experimental data allows the conclusion that the wave function in the 7Li-n-n model describes the cross section better than in the α-t-2n model.  相似文献   

11.
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   

12.
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   

13.
14.
Measurements of the differential cross sections for the elastic scattering of 30.5 MeV protons by 24Mg and for the inelastic scattering to the 1.37, sum of 4.12 and 4.23, 5.22 and 6.0 MeV states are reported. Optical model fits to the elastic data, a distorted wave calculation for the first excited state, and coupled channel calculations are also presented.  相似文献   

15.
16.
The elastic scattering of high-energy protons from zero-spin nuclei is considered within the framework of Glauber theory. The sensitivity of the cross sections to the nuclear structure and to the proton-nucleon amplitude is studied. Results of calculations demonstrating the investigated effects are presented for the case of 1 GeV proton scattering from 4He, 16O and 58Ni.  相似文献   

17.
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   

18.
The cross sections of elastically scattered9Li and6He on208Pb were measured. The scattered particles were detected by an annular CR-39 solid state nuclear track detector and the monitoring was done with a triple telescope of silicon detectors. The classical and optical model analyses of the measured elastic cross sections have been carried out. It was shown that the peripheral9Li interaction region has a rather high transparency. Strong dynamical polarization of9Li ions in the process of scattering is suggested.  相似文献   

19.
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   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号