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1.
The spin alignment Pzz of12C(2 1 + ) produced in12C+12C inelastic scattering at bombarding energies in the region of known resonances between Ecm=18.5 and 32.8 MeV has been determined with a γ-ray detector positioned in the direction of the scattering normal. The values obtained in the centers of three resonances as well as those obtained off-resonance are spread over a range between ?.05 and +.80 with no clear indication in favour of simple pictures of molecular resonances.  相似文献   

2.
The predictions for the spin alignment in the single 2+ excitation in 12C + 12C scattering in four typical models, i.e., the Austern-Blair diffraction model, the Band Crossing Model, the DWBA model and the strong-coupling model, are compared among themselves and with experiment.  相似文献   

3.
The spin alignment of the12C2 + state in inelastic scattering of12c on64zn at EL=65 MeV has been measured using the γ-recoil-in-flight method. Good agreement with coupled channel calculations are obtained. The sensitivity of the spin alignment to reaction models is discussed.  相似文献   

4.
5.
Absolute differential cross-sections ofp+12C elastic scattering have been measured atθ cm=89.1°, 118.7°, 146.9° for bombarding energies between 0.3 and 2.0 MeV. Revised level parameters of the first three excited states in13N have been extracted with aR-matrix analysis. It is shown that the influence of the bound ground-state of13N has an appreciable effect on low-energy scattering. Recent predictions concerning Mott-Schwinger polarization are also discussed.  相似文献   

6.
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   

7.
Excitation functions for12C+12C elastic and inelastic scattering to 2+ level have been measured over the energy range 30–60 MeV (cm) by 250 keV steps using the kinematical coincidence method. The intermediate structure resonances disappear aboveE cm=35 MeV while the broad and irregular structure becomes a general feature of the interaction at higher energies.  相似文献   

8.
在Glauber多重散射理论框架下,使用跃迁密度方法和三种NN湮没势,计算了46.8MeV的反质子在12C上的非弹性散射微分截面.理论曲线与实验数据符合得较好.  相似文献   

9.
The elastic and inelastic scattering of 12C by 12C has been measured over a wide angular range employing a kinematical analysis with the help of position-sensitive detectors. The bombarding energy was varied in 200 keV steps between 10 and 37.6 MeV. The cross sections are analysed in the framework of compound fluctuations and the direct reaction model.  相似文献   

10.
在Glauber多重散射理论框架下,使用跃迁密度方法和三种N湮没势,计算了46.8MeV的反质子在12C上的非弹性散射微分截面. 理论曲线与实验数据符合得较好. 关键词: Glauber理论 反质子 非弹性散射 湮没势 跃迁密度  相似文献   

11.
B Ghosh  R Singh 《Pramana》1987,29(2):155-161
The data on the ϑc.m.=180° excitation functions of12C+24Mg,12C* (4.43 MeV)+24Mg and12C+24Mg*(1.36 MeV) from 12.27 to 22.80 MeV, 16.53 to 27.47 MeV, and 11.33 to 26.40 MeV(c.m.) respectively have been subjected to statistical analysis. The effect of averaging interval, employed for data reduction, on the coherence widths as obtained from the autocorrelation function has been studied. The fluctuating features of the cross-sections turn out to be consistent with the statistical model expectations.  相似文献   

12.
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   

13.
Neutron total, scattering and (n; n′,γ) cross sections of elemental yttrium (89Y) were measured in the few-MeV region. The neutron total-cross-section measurements were made with broad resolutions from ≈0.5 to 4.2MeV in steps of ?0.1 MeV. Neutron elastic- and inelastic-scattering cross sections were measured from ≈1.5 to 4.0 MeV, at incident-neutron energy intervals of ≈50keV and at ten or more scattering angles distributed between 20 and 160 degrees using neutron detection. Inelastic-scattering cross sections were also determined using the (n; n′,γ) reaction at incident energies from 1.6 to 3.8 MeV at intervals of 0.1 MeV. Gamma-rays and/or inelastically-scattered neutrons were observed corresponding to the excitation of levels at: 909.0±0.5, 1,507.4 ±0.3, 1,744.5±0.3, 2,222.6±0.5, 2,530±0.8, 2,566.4±1.0, 2,622.5±1.0, 2,871.9 ±1.5, 2,880.6±2.0, 3,067.0±2.0, 3,107.0±2.0, 3,140.0±2.0, 3,410.0±2.0, 3,450.0±2.0, 3,504.0 ±1.5, 3,514.0±2.0, 3,556.0±2.0, 3,619.0±3.0, 3,629.0±3.0 and 3,715.0±3.0 keV. The experimental results are discussed in terms of the spherical-optical-statistical, coupledchannels, and core-coupling models, and in the context of previously reported excitedlevel structure.  相似文献   

14.
Angular distributions of cross sections have been measured for single nucleon transfer reactions induced by 344.5 MeV12C ions on a12C target. DWBA analyses have been performed for transitions to discrete final states. Spectroscopic information has been derived and is compared with results of other studies.  相似文献   

15.
16.
Z A Khan  I Ahmad 《Pramana》1977,8(2):149-158
The alpha-particle model has been applied to calculate the elastic and the 2+ inelastic angular distribution of 1 GeV protons on12C within the framework of Glauber multiple scattering theory. The results are compared with the recent experimental data and with some previous calculations. The model gives a fairly good account of the inelastic data and its predictions for the elastic scattering are essentially the same as those of the shell model.  相似文献   

17.
High-resolution elastic and inelastic data were obtained for π+ and π? scattering 12C. Spectra were taken with the SIN pion spectrometer at 148 MeV over a wide angular range.  相似文献   

18.
The elastic and inelastic scattering of12C on12C has been measured in the angular range between 2.8° and 70.4° in the c.m. system atE Lab =300 MeV. Optical model calculations have been performed with Woods-Saxon and folded potentials, the ground state and the first 2+-state were coupled in the calculations. The large cross sections of the elastic scattering at large angles is related to the nuclear rainbow scattering, which is centered at about 56°. This requires a potential depth of 100 MeV at a distance of 3 fm, the fit to the data is sensitive down to this region. The calculations with the folded potential show a better agreement with the data than those with the Woods-Saxon shape. The total reaction cross section of 1,420 mb, obtained from the optical model analysis, corresponds to the geometrical value; no transparency is observed.  相似文献   

19.
20.
A barrier-top-resonance model calculation is found adequate to describe the gross structure behavior thus far observed in 12C + 12C and16O + 16O inelastic scattering excitation functions.  相似文献   

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