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1.
本文在E_d=0.1—2.5MeV能量范围内,研究了Be~9(d,p_0)Be~(10)(0),Be~9(d,p_1)Be~(10)(3.368MeV),Be~9(d,t_0)Be~8(0),Be~9(d,α_0)Li~7(0)及Be~9(d,α_1)Li~7(0.478MeV)诸反应。在E_d=0.150,0.220,0.401,0.706,1.005,1.301,1.484,1.750,2.000,2.250和2.500MeV共十一个能量上分别测量了这五群出射粒子在θ_L=10—155°区间的角分布。在θ_L=135°,E_d=0.1—2.5MeV,在θ_L=95°,E_d=0.1—2.2MeV,和在θ_L=112.5°,E_d=0.5—2.5MeV测量了Be~9(d,p_0)Be~(10)的激发函数。在θ_L=135°和112.5°,E_d=1.2MeV,用较厚靶(100—300μg/cm~2)测量了Be~9(d,p_0)Be~(10)(0)反应的截面绝对值,结果为σ_p_0(θ_L=135°)=1.60mb/sr,σ_p_0(θ_L=112.5°)=1.55mb/sr。这样就得到了在此能区内,这五群出射粒子的截面情况。对所得结果进行了一些讨论。  相似文献   

2.
The angular distributions of the (p, d), (d, t) and(3He, ) reactions on13C have been analysed within the framework of DWBA in which additional information on nuclear vertex constants was introduced. Although all these reactions seem to be similar single nucleon transfer, their mechanism is shown to be quite different and so is the information extracted thereof. While from the (p, d) reactions spectroscopic factors may be extracted unambiguously, from the (d, t) reactions it is possible to obtain directly the values of vertex constants only, which in turn are consistent with those determined by extrapolation of the experimental cross sections of the (p, d) reactions to the pole.In the case of (3He, ) reactions, however, the analysis indicates inadequacy of the DWBA concerning the calculations of central partial amplitudes. For a more reliable extraction of structural information, besides the correct normalization of peripheral amplitudes, a contribution of more complex mechanisms must be taken into account.  相似文献   

3.
Two 1Πg states of Na2 for v≤13 have been observed by using optical-optical double resonance (OODR) fluorescence excitation spectroscopy. The intermediate levels in B1Πu state are identified by the numerical calculations with the molec-ular constants for B1Πu←X1Σg+ transitions and confirmed by the complemen-tary A1Σg+←X1Σg+ polarization spectra. Absolute vibrational numberings of the (6d)1Πg and (7d)1Πg states are determined by comparing the experimental OODR excitation intensities with the simulated Franck-Condon factors. The Dnnham coef-ficients and the Rydberg-Klein-Rees (RKR) potential energy curves of the (6d)1Πg, (7d)1Πg states are reported.  相似文献   

4.
The 2H(d, γ)4He capture reaction and the 2H(d, p)3H and 2H(d, n)3He transfer reactions at very low energies are studied in an extended microscopic cluster model with a realistic nucleon–nucleon force. Our results show that the tensor force in realistic interactions plays an essential and indispensable role to reproduce the very low-energy astrophysical S factor of these reactions.  相似文献   

5.
The (2)H(d,p)(3)H, (2)H(d,n)(3)He, and (2)H(d,γ)(4)He reactions are studied at low energies in a multichannel ab initio model that takes into account the distortions of the nuclei. The internal wave functions of these nuclei are given by the stochastic variational method with the AV8' realistic interaction and a phenomenological three-body force included to reproduce the two-body thresholds. The obtained astrophysical S factors are all in very good agreement with the experiment. The most important channels for both transfer and radiative capture are identified by comparing to calculations with an effective central force. They are all found to dominate thanks to the tensor force.  相似文献   

6.
The ratios of the radiative transition probabilities for the lines of the P, Q, and R branches of the (4d)r 3Π g ? , (4d)s 3Δ g ? → (2p) c 3Π u ± band systems of the H2 molecule have been measured for the first time. Significant (to two orders of magnitudes) differences are found between the experimental values and the adiabatic theory predictions. It is established that the results of the nonadiabatic calculation performed by us in the pure-precession approximation taking into account the electronic-rotational interaction of the 4d 3Πg and 4d 3Δg states are in agreement with the experimental data. The optimal energies of rovibronic levels of the r 3Π g ? , s 3Δ g ? , c 3Π u ? , and c 3Π u + states have been found and reidentification of 11 from 54 spectral lines, assigned previously to the (0-0) and (1-1) bands, was performed.  相似文献   

7.
8.
本文在Ed=0.1—2.5MeV能量范围内,研究了Be9(d,p0)Be10(0),Be9(d,p1)Be10(3.368MeV),Be9(d,t0)Be8(0),Be9(d,α0)Li7(0)及Be9(d,α1)Li7(0.478MeV)诸反应。在Ed=0.150,0.220,0.401,0.706,1.005,1.301,1.484,1.750,2.000,2.250和2.500MeV共十一个能量上分别测量了这五群出射粒子在θL=10—155°区间的角分布。在θL=135°,Ed=0.1—2.5MeV,在θL=95°,Ed=0.1—2.2MeV,和在θL=112.5°,Ed=0.5—2.5MeV测量了Be9(d,p0)Be10的激发函数。在θL=135°和112.5°,Ed=1.2MeV,用较厚靶(100—300μg/cm2)测量了Be9(d,p0)Be10(0)反应的截面绝对值,结果为σ(p0)L=135°)=1.60mb/sr,σ(p0)L=112.5°)=1.55mb/sr。这样就得到了在此能区内,这五群出射粒子的截面情况。对所得结果进行了一些讨论。  相似文献   

9.
用活化法和迭靶技术,测量了入射氘核能量从3.2到13.3MeV范围内,Mo(d,x)~(95m)Tc,Mo(d,x)~(96g)Tc和Mo(d,x)~(97m)Tc反应的激发函数,并与复合核统计模型理论计算作了比较。  相似文献   

10.
《Nuclear Physics A》1997,625(3):598-620
At the Munich Tandem Accelerator the reactions 125Te(d, p)126Te, 126Te(d, d′)126Te and 127I(d, 3He)126Te were measured with deuteron energies between 24 and 28 MeV up to excitation energies of about 3.2 MeV. Using γ-lines from previous (n,γ), (n,n′γ) and (γ,γ′) experiments, a level scheme of 126Te up to above 3 MeV was established. The results are compared with quasiparticle-phonon model calculations.  相似文献   

11.
Total cross sections and excitation functions up to 11·8 MeV have been measured for the Ce142(d,p), -(d,n) and -(d, 2n) reactions by the activation method. The cross sections found forE d=11·8 MeV are 187mb, 54 mb and 535 mb, respectively. By comparing these results with cross sections calculated from the statistical theory of nuclear reactions it can be shown that the (d,p)-reaction and nearly the whole (d,n) -reaction proceed by stripping mechanism.  相似文献   

12.
13.
在多通道量子亏损理论框架下,利用相对论多通道理论,分别在冻结实近似和考虑偶极极化下计算钪原子的Jπ=(3/2)-,(5/2)-的三个收敛于[Ar]3d4s(1D2)的自电离里德伯系列的能级.对3d4s(1D2)np2D3/2和3d4s(1D2)nf2F5/2这两个系列,计算结果表明,考虑偶极极化效应后,理论计算和实验测量的量子数亏损之差普遍小于0.01.而对3d4s(1D2)nf2D3/2系列,考虑偶极极化效应后的结果和仅考虑冻结实的结果比较接近,理论计算和实验测量的量子数亏损之差普遍在0.04左右.  相似文献   

14.
Cross sections for some (n,d*),(n,t) and (n,n'α)reactions have been measured by using the activation method relative to cross sections of 27Al(n,α)24Na or 93Nb(n,2n)92mNb reactions in neutron energies around 14MeV.In this paper some of the published cross section data have also been listed and compared with our results.The neutron energies were determined by the method of cross section ratios for the reactions of 90Zr(n,2n) 89m+gZr and 93Nb(n,2n)92mNb.  相似文献   

15.
本文报告了En~14MeV中子以27Al(n,α)24Na或93Nb(n,2n)92mNb反应截面为中子注量标准测得的92Mo(n,d*)91mNb,106Cd(n,d*)105Ag;54Fe(n,t)52m+gMn,58Ni(n,t)56Co;51V(n,n'α)47Sc和92Mo(n,n'α)88Zr的反应截面.文中还列举了能收集到的数据以作比较,中子能量是用铌锆截面比法测定的.  相似文献   

16.
Data from the recent PSI high statistics experiment on d μ d fusion are used to measure the stripping process in d μ d→ n+μ,3He and test current calculations of the stripping process. The PSI results in μ3He capture are also used to remove a troubling background from this measurement. Combination of these results with the old dμ t sticking analysis slightly raise and improve that result to ωs= (0.58± 0.04)% and indicate that theory and experiment can meet if theoretical stripping is increased only at the beginning of the track. This conclusion is in accord with the new stripping calculations where excited state stripping is increased significantly. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
All available data of the mirror fusion reactions D(d, n)3He and D(d, p)3H have been subjected to a new analysis in order to extract the matrix elements of all 16 transitions necessary for inclusion of alll2 waves. Their energy dependence was assumed to be governed solely by Coulomb penetrabilities. The Levenberg-Marquardt algorithm was used to fit all experimental data. The experimental data are reproduced satisfactorily. The results compare well with anR-matrix analysis and with refined resonating group calculations. No suppression of quintet entrance-state transitions and therefore no neutron suppression in polarized fusion can be derived from this analysis.This work was funded by the German Federal Ministers for Research and Technology (BMFT) under the contract numbers 06-OK-153 and 06-OK-272  相似文献   

18.
采用完全对角化方法,以尖晶石结构的ZnAl2O4:Cr3+,ZnGa2O4:Cr3+和MgAl2O4:Cr3+系列晶体为例,联系晶格局域结构,对三角对称下3d3离子2E态g因子性质进行了研究.研究中考虑了包括自旋与自旋相互作用、自旋与另一轨道相互作用以及轨道与轨道相互作用在内的微小磁相互作用.对ZnAl2O4:Cr3+ 体系2E态g因子给出了理论解释,说明了ZnGa2O4:Cr3+体系的g‖(E′)应为负值,并从理论上预测了MgAl2O4:Cr3+体系2E态g因子数值.研究表明,微小磁相互作用对2E态g因子的贡献较大,在计算中是不可忽略的;相对于基态g因子来说,2E态g因子随晶格局域结构变化较为敏感.  相似文献   

19.
20.
Total cross sections of electron scattering by eight molecules NF3, PF3, N(CH3)3, P(CH3)3, NH(CH3)2, PH(CH3)2, NH2CH3 and PH2CH3, which have some structural similarities, are calculated at the Hartree-Fork level by the modified additivity rule approach [D.H. Shi, J.F. Sun, Z.L. Zhu, H. Ma, Y.F. Liu, Eur. Phys. J. D 45, 253 (2007); D.H. Shi, J.F. Sun, Y.F. Liu, Z.L. Zhu, X.D. Yang, Chin. Opt. Lett. 4, 192 (2006)]. The modified additivity rule approach takes into considerations that the contributions of the geometric shielding effect vary as the energy of incident electrons, the dimension of target molecule, the number of electrons in the molecule and the number of atoms constituting the molecule. The present investigations cover the impact energy range from 30 to 5000 eV. The quantitative total cross sections are compared with those obtained by experiments and other theories. Excellent agreement is observed even at energies of several tens of eV. It shows that the modified additivity rule approach is applicable to carry out the total cross section calculations of electron scattering by these molecules at intermediate and high energies, in particular over the energy range above 80 eV or so. It proves that the microscopic molecular properties, such as the geometrical size of the target and the number of atoms constituting the molecule, are of crucial importance in the TCS calculations. The new results for PH(CH3)2 and PH2CH3 are also presented at energies from 30 to 5000 eV, although no experimental and theoretical data are available for comparison. In the present calculations, the atoms are still represented by the spherical complex optical potential, which is composed of static, exchange, polarization and absorption terms.  相似文献   

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