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1.
Coulomb excitation probabilities of the first 2 + states of 122Te and 130Te have been determined. The measurement was performed by resolving the inelastically and elastically scattered 4He and 16O projectiles using eight surface barrier detectors between 44° and 173°. Quadrupole moments Q2+ as well as B(E2, 0+ → 2+) values were deduced. The Q2+ found for the positive sign of the 22+ interference term are ?0.46±0.05 e · b and ?0.15±0.10 e · b for 122Te and 130Te respectively. 相似文献
2.
Coulomb excitation probabilities of the first 2+ states of 124Te, 126Te and 128Te have been determined. The measurement was performed by resolving the inelastically and elastically backward scattered 4He and 16O projectiles using an annular surface barrier detector. Quadrupole moments (Q2+) as well as the B(E2, 0+ → 2+) values were extracted by analyzing the excitation probabilities with the Winther-de Boer multiple Coulomb excitation program. The Q2 deduced for the positive sign of the 2+ interference term are ?0.41 ± 0.08 e · b, ?0.144 ± 0.11 e · b and ?0.12 ± 0.09 e · b for 124Te, 126Te and 128Te, respectively. 相似文献
3.
Energy spectra of 130 MeV 3He scattered from 24Mg, 90Zr, 120Sn and 208Pb have been measured. The spectra exhibit a pronounced giant resonance (GR) structure in the excitation energy region around . The GR angular distributions as well as those corresponding to the first 2+ levels in 24Mg and 120Sn have been obtained for angles 7° ≦ θL ≦ 35°. Distorted wave calculations using the optical model parameters fitting the elastic data resulted in good fits to the 2+ levels. For 24Mg, 90Zr and 120Sn the shapes of the GR angular distributions are well fitted by L = 2 curves alone. However, for 208Pb both L = 2 and L = 4 curves give fits of comparable quality. 相似文献
4.
The g-factor of the state in92Nb(τ = 6.2 μsec) was determined by means of perturbed angular distribution methods using the 92Zr(p, n)92Nb reaction in a liquid alloy. The extracted magnetic moment is discussed in terms of the core-polarization effect. 相似文献
5.
The spectroscopic quadrupole moment of the isomeric 6+' (2552 keV) state of 117Sn has been derived from TDPAD measurements in a Cd metal host target at 500 K as . The calibration of the effective field gradient for Sn in Cd at 500 K, given by Herrlander et al. has been used. A comparison of the results with shell model estimates makes a mixed configuration of for the 6+ state most likely. 相似文献
6.
The energy levels of 123I and 125I have been studied in the 122, 124Te(3He, d)123, 125I reactions at 24 MeV bombarding energy. The reaction products were analysed with an Enge split-pole magnetic spectrograph. A total of 57 levels below 3.3 MeV in 123I and 79 levels below 4.1 MeV in 125I were observed. Angular distributions were measured and compared with DWBA calculations to obtain orbital angular momentum transfers and spectroscopic strengths. The results were compared to previous radioactive decay studies and to theoretical energy level calculations. 相似文献
7.
M. Neiman R. Kalish D.R.S. Somayajulu B. Herskind F. Genovese L. Grodzins 《Physics letters. [Part B]》1974,52(2):189-191
The quadrupole moments of the first 2+ states of 130,134Ba were measured using the reorientation precession technique. Prolate deformations were determined for both nuclei. The quadrupole moments found were Q = ?0.33 ± 0.24 b and ?0.31 ± 0.24 b for 130Ba and 134Ba, respectively. 相似文献
8.
R. Kalish J.A.G. De Raedt A. Holthuizen W.A. Sterrenburg G. Van Middelkoop 《Nuclear Physics A》1978,311(3):507-517
The g-factors of the first-excited 2+ states of 144, 146, 148Nd were deduced from precession measurements in which the excited nuclei recoil through (TF IMPAC) or stop in (IMPAC) magnetized iron. The transient and static hyperfine fields which are active in these cases have been calibrated. The results for the g-factors, combined with previous data which were reanalyzed in the present work, are: g144 = 0.15 ± 0.02, g146 = 0.25 ± 0.04, g148 = 0.32 ± 0.04. The g-factor for 144Nd, which is abnormally low for a collective 2+ state, cannot be accounted for theoretically. 相似文献
9.
The g-factor of the 10? isomeric state in 208Bi has been measured by the method of inbeam NMR-PAD. From the experimental value the magnetic moment of the neutron hole state is deduced. The result is compared with experimental values of neighbouring nuclei and theoretical predictions. 相似文献
10.
M. Hass E. Dafni H.H. Bertschat C. Broude F.D. Davidovsky G. Goldring P.M.S. Lesser 《Nuclear Physics A》1984,414(2):316-332
The determination of the sign of the quadrupole deformation at high spins requires an observation of the electric quadrupole interaction of polarized isomers in single crystals of non-cubic metallic hosts. The 54Fe(10+) isomer was polarized, subsequent to its population by the (12C, p2n) reaction, by passage through an array of tilted carbon foils. The isomers were then recoil implanted into single crystals of zinc and cadmium and the tune differential modulations of the angular distribution of decay γ-rays were observed. Nuclear polarization values of PI = 0.08(3)?0.18(5) were found for 13–17 polarizing foils, respectively, and a positive sign of the quadrupole moment was deduced. An improved value was established for the quadrupole moment: , in agreement with current shell-model predictions. 相似文献
11.
Masumi Ohshima Eisuke Minehara Mitsuhiko Ishii Takashi Inamura Akira Hashizume 《Nuclear Physics A》1985,436(3):518-537
The ground-state rotational band in 167Er has been investigated through multiple Coulomb excitation with a 160 MeV 35Cl beam. Excited states up to were established by measuring γγ coincidences and γ-ray angular distributions. Gamma-gamma angular correlations were also measured. Nuclear lifetimes of levels up to spin have been determined from Doppler-broadened γ-ray lineshapes, and B(M1) and B(E2) values of intra-band transitions deduced. Considerable signature dependence was observed for level energies and M1 transition probabilities. A Coriolis band-mixing calculation was carried our for comparison with the experimental results. The measured M1 transition probabilities are compared to calculations based on a particle-rotor model, a cranking model, and a microscopic model with quantum-number projection. 相似文献
12.
A quadrupole moment of 37?8+14 b has been deduced for the 40 ps shape isomer in 236Pu. The value has been derived from a measured delayed fission fragment angular distribution with an anisotropy of 1.48 ± 0.15 for the isomeric decays at 30°. The deformation of the second minimum expressed by the axes ratio of a spheroid is found to be 2.0 ± 0.3. 相似文献
13.
R.H. Spear M.T. Esat M.P. Fewell D.C. Kean T.H. Zabel A.M. Baxter S. Hinds 《Nuclear Physics A》1980,345(1):252-262
The static quadrupole moments Q2+ and B(E2; 0+ → 2+) values of the 2+ first excited states of 200Hg and 202Hg have been determined using the reorientation effect in Coulomb excitation. An annular silicon surface-barrier detector was used to detect backscattered 4He, 12C and 16O projectiles. It is found that for 200Hg, Q2+ = +1.07 ± 0.19 e · b(+0.98 ± 0.19 e · b) for destructive (constructive) interference from the 2+′ state, and B(E2; 0+ → 2+) = 0.853 ± 0.007 e2 · b2. For 202Hg, we find Q2+ = +1.01 ± 0.13 e · b (+0.87 ± 0.13 e · b) and B(E2; 0+ → 2+) = 0.605 ± 0.005 e2 · b2. The Q2+ value obtained for 200Hg is in agreement with previous work, but that for 202Hg is not. The results obtained are compared with the predictions of various nuclear models, and the mass dependence of Q2+ in the region 182 ≦ A ≦ 206 is examined. 相似文献
14.
M.T. Esat M.P. Fewell R.H. Spear T.H. Zabel A.M. Baxter S. Hinds 《Nuclear Physics A》1981,362(1):227-240
The static electric quadrupole moment Q2+ and the B(E2; 0+ → 2+) value of the 2+ first excited state of 204Hg have been determined using the reorientation effect in Coulomb excitation. An annular Si surface-barrier detector was used to detect back-scattered 4He, 12C and 16O projectiles. In a subsidiary experiment, spectra were obtained from 204Hg(p, p')204Hg using Si surface-barrier detectors, and the results were used in conjunction with previously existing data to provide information on higher states of 204Hg which might participate in the Coulomb excitation of the 2+ state. From a 3-level analysis, we find Q2+ = +0.40 ± 0.20 e · b and B(E2; 0+ → 2+) = 0.423 ± 0.005 e2 · b2. These results are in good agreement with the predictions of particle-vibrational coupling calculations. The value obtained for is substantially smaller in magnitude than values of Q2+ previously determined for 198, 200, 202Hg. 相似文献
15.
The gyromagnetic ratios of the first excited Jπ = 2+ states of 50,54Cr, 54Fe and 70Ge have been determined by the ion-implantation perturbed angular correlation technique (IMPAC) with ferromagnetic Gd as stopping material. The g-factors were extracted from the measured precession angles with use of known lifetimes, static hyperfine magnetic fields and transient hyperfine magnetic field data for fast ions traversing ferromagnetic lattices. The deduced values are 0.59 ± 0.10, 0.56 ± 0.10, 1.08±0.19 and 0.38±0.08, respectively. With the exception of 54Fe all g-factors are close to the collective value. A re-evaluation of earlier IMPAC data on 70, 72, 74, 76Ge with Fe as stopping material has been performed. The value obtained for 70Ge is in good agreement with the one measured in this work. 相似文献
16.
The nuclear g-factor of the 2543 keV, 7+ state 40K has been measured as g = 0.59 ± 0.10. Time-integral perturbed angular distributions were measured in an external magnetic field and, after implantation, in the hyperfine field at potassium in nickel. The experimental value is discussed within the , configurations. 相似文献
17.
18.
Using the atomic beam magnetic resonance method the hyperfine structure separation of has been measured in the atomic ground state. From the hyperfine structure splitting the nuclear magnetic dipole moment has been deduced. The results are: Δν = 4500 (68) MHz, μI = 0.641(10)μN. This is an improvement of approximately one order of magnitude compared to a previous measurement. The quoted value of the magnetic dipole moment includes corrections for the hyperfine structure anomaly and for diamagnetic shielding. 相似文献
19.
Angular distributions of the polarization in the elastic scattering of 3He by 3He have been measured at eight energies between 18 and 33 MeV, corresponding to excitation of 6Be between 20.5 and 28 MeV. The measurements were made using the 33 MeV polarised 3He beam at the University of Birmingham Radial Ridge cyclotron and a small gas target. The data have been analysed in terms of real and complex phase shifts. The deduced phase shift energy dependence cannot be associated with a single isolated level in 6Be, however an application of the two-level R-matrix formula reveals some broad L = 3 structures around Ex = 25 MeV. 相似文献
20.
Activation cross sections for the 89Y(n, 2n)88Y reaction at neutron energies between 12.6 and 17.8 MeV have been measured by using the mixed-powder method and γ-ray detection by a Ge(Li) spectrometer. Using the 27Al(n, α)24Na reaction for monitoring the neutron flux, the measured cross-section values for the 89Y(n, 2n)88Y reaction were found to be 331±32 mb, 603±58 mb, 820±79 mb, 1040±100 mb, 1072±103 mb, 1172±112 mb, 1221±117 mb and 1218±117 mb at the respective incident neutron energies of 12.6±0.1 MeV, 13.3±0.1 MeV, 14.0±0.4 MeV, 14.9±0.3 MeV, 15.1±0.3 MeV, 16.0±0.4 MeV, 16.7±0.5 MeV and 17.8±0.7 MeV. The measured values are compared with the experimental values of others and with the theoretical values obtained from calculations based on the statistical model for the formation of a compound nucleus and its subsequent emission of neutrons. 相似文献