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1.
We have measured 16O17O elastic cross sections at 22 MeV between 65°–140° to ± 1 %. The observed oscillatory interference between Coulomb scattering and the neutron transfer process is analyzed using exact finite-range DWBA. A model-independent value of C?2 = 0.82 ± 0.07 is obtained for the coupling constant of the 1d52 neutron in 17O. We also present an analysis of data on magnetic electron scattering from 17O, which yields precise information on the magnitude and the radial shape of the 1d52 neutron bound-state wave function. With this we relate the coupling constant to the spectroscopic factor and find S = 1.04 ± 0.11. We show that the magnetic electron scattering data alone yield S = 1.04 ± 0.10. Combining these results with earlier work we recommend C?2 = 0.79 ± 0.04 and S = 1.03 ± 0.07 as best values. This spectroscopic strength corresponds to (91 ± 7) % of the full single-particle value.  相似文献   

2.
The 91Zr(d, 3He) reaction was studied at a deuteron energy of 28 MeV. Angular distributions were measured from 13° to 47°; lp values were extracted for the prominent lines of 90Y. The lp values and transition strengths were determined by DWBA analysis. The angular distributions for the p12)(νd52) doublet (g.s. and 0.20 MeV state) exhibit the characteristic l = 1 shape. States at 1.42, 1.57, 1.64 and 1.81 MeV were also populated strongly in the (d, 3He) reaction; the 1.42, 1.57 and 1.81 MeV levels contain l= 1 transition strength and are most likely members of the p32?1)(νd52) multiplet. The 2.03 MeV state has a characteristic l = 3 angular distribution and is suggested to be the only member of the f32?1)(νd52) sextet to be unambiguously observed in this study, most probably the 5? or 4? member. The members of the g52)(νd92) sextet were populated weakly (less than 100 μb/sr) in this reaction.  相似文献   

3.
The 48K, 49K and 50K nuclides have been produced in high energy fragmentation and analyzed by mass spectroscopy techniques. Their half-lives have been measured as 6 ± 1 s, 1.1 ± 0.3 s and and 0.7 ± 0.3 s, respectively. The γ-rays from their radioactive decay have been observed and the corresponding γ-intensities measured. The nuclide 50K is shown to be a delayed neutron emitter. The antianalog states in the daughter Ca nuclei with a (1d32)? neutron configuration, preferentially populated in the β-decay, have been located. The corresponding 1d32 neutron single-particle energy is found to remain approximately constant for these neutron-rich Ca isotopes.  相似文献   

4.
The level schemes of the nuclei 134,136La have been studied by means of in-beam γ-ray spectroscopic methods following the (α, 3n) and (p, 3n) reactions. New isomers with half-lives of 29 ± 5 μs and 17 ± 4 ns have been discovered in 134La and 136La, respectively. Low-lying levels and isomers in 134,136La have been interpreted as members of multiplets having d52vd32), (πd52vs?112) andd52vh?1112) configurations.  相似文献   

5.
The quadrupole interaction frequencies ω0 = 3eQ1Vzz41(21-1) h? in the 5? state of 118Sn have been measured by time differential perturbed angular correlation technique in Sn, Sb and (95% Sn+5% Sb) environments. The ω0 for 116Sn was determined in Sn environment only. With the help of the known electric field gradient 1) of Sn in a Sn lattice the quadrupole moments have been deduced as Q(5?, 118Sn) = ±0.10(4) b and Q(5?, 116Sn) = ±0.165(60) b. These values together with the known2) quadrupole moment of the analogous 5? state in 120Sn are interpreted in terms of the pure single-particle model. The data exhibit the expected strong systematic variation of QI with the number of particles in the h112. subshell which is being filled with 1, 3 and 5 neutrons in 116Sn, 118Sn, and 120Sn, respectively.  相似文献   

6.
Angular distributions of γ-rays from the 2H(d, γ)4He reaction have been measured at the deuteron energies Ed = 6.05, 8.96 and 11.67 MeV with a 12.7 cm × 15.2 cm NaI(Tl) crystal enclosed in a Cerenkov anticoincidence shield. A least-square fit of the angular distributions indicates that the differential cross section is proportional to sin2θ cos2θ and that the process proceeds through an E2 transition of the type 1D21S0.  相似文献   

7.
The results of high-resolution studies of the 91Zr(d, p) reaction at Ed = 12 MeV and the 90Zr(t, p) reaction at Et = 11.85 MeV are presented. Absolute cross sections have been measured for both reactions and (d, p) spectroscopic factors determined. A comparison of these results with earlier data has been made, and although many of the previous assignments have been confirmed, many new features concerning the structure of 92Zr have been discovered. Shell-model calculations have been performed for 91Zr and 92Zr using a neutron space which includes the 2d52, 3s12, 2d32, 1g72 and 1h112 orbits and a proton space comprising the 1g92 and 2p12 orbits. Realistic proton-neutron and neutron-neutron interactions based on the Sussex matrix elements were used in the calculations. Spectroscopic factors have been calculated for the 90Zr(d, p) and 91Zr(d, p) reactions and cross sections calculated for the 90Zr(t, p) reaction. In general, good agreement between the theoretical and the experimental results has been obtained.  相似文献   

8.
The rotational structure of about 40 bands of 12C2HD observed in the region 6000?600 cm?1 has been measured and interpreted with the purpose of determining a comprehensive set of molecular constants for this isotopic variety of acetylene. Combining these data with the results for 12C2H2 and 12C2D2, a reevaluation of the equilibrium internuclear distances for the acetylene molecule has been made: re(CH) = 1.06215 ± 17 × 10?5A? and re(CC) = 1.20257 ± 9 × 10?5A? were obtained. This paper presents all the molecular constants derived in this study.  相似文献   

9.
The doubly odd nucleus 140Pr has been investigated by means of the 141Pr(d, t)140Pr and 140Ce(p, nγ)140Pr reactions. Twenty-eight levels, up to 1300 keV excitation, were observed in the pickup study. DWBA analysis was used to determine l-values and spectroscopic factors for all but a few which are very weakly populated. Gamma-ray angular distributions, measured at Ep = 4.78 MeV for the five strongest γ-rays, show appreciable nuclear alignment and demonstrate the feasibility of such experiments in this mass region. Taken together, the two studies have permitted the identification of the 12 levels expected from the low-lying (π2d52ν2d32?1), (π2d52ν3s12?1), (π1g72ν2d32?1) and (π1g72ν3s12?1) configurations. Tenta assignments for the strong odd-parity states are suggested on the basis of their spectroscopic factors.  相似文献   

10.
EPR of 61Ni+ doped CuGaS2 at 4.2 K leads to the following experimental data: g = 1.918 ± 0.006 A  < 12 × 10-4cm-1, g = 2.328±0.006 A = (65±2) × 10-4cm-1. High axial field splitting of 2T2 state stabilizes the center against Jahn-Teller interaction. Covalency reduction factor k is 0.76.  相似文献   

11.
The (1-0), (2-0), and (3-0) transitions of 15N16O and 15N18O are investigated. The wavenumbers of the rotation-vibration lines are reported for the overtone bands and the 2Π32-2Π12 (1-0) subband. It is shown that in the data reduction it is advantageous to calculate first merged spectroscopic constants ignoring the Λ-type doubling. The vibrational constants ωe, ωexe, ωeye and the vibrational dependence of the rotational constants are determined. The study of 15N18O allows the determination of the equilibrium values of the centrifugal distortion correction ADe to the spin-orbit constant and of the spin-rotation constant γe from the isotopic invariance of the ratios ADeBe and γeBe. It is found that ADeBe = (?3.9 ± 1.3) × 10?6 and γeBe = (?4.00 ± 0.05) × 10?3.  相似文献   

12.
Lifetime and g-factor measurements have been made with pulsed beam-γ time-differential techniques using the 89Y(α, 2n)91Nb and 88Sr(α, n)91Zr reactions. A mean lifetime τ = 14.4 ± 0.5 nsec and a g-factor of 1.26 ± 0.04 were obtained for the 132? 1985 keV level in 91Nb and τ = 41.9 ± 1.2 nsec and g = 0.70 ± 0.01 were obtained for the 152? 2288 keV level in 91Zr. These results are compared to theoretical calculations for g92)2p12) and g92)(πp12)(vd52) configurations in 91Nb and 91Zr, respectively.  相似文献   

13.
C.P. Swann 《Nuclear Physics A》1973,201(3):534-540
The Doppler-broadened 7.117 MeV line from the 19F(p, αγ)16O reaction has been used to resonantly excite levels in 208Pb at 7071±2 and 7091±2 keV, in 207Pb at 7186±5 and 7206±5 keV and in 209Bi at 7179±5 and 7202±5 keV. On the basis of angular distribution measurements the 7071 and 7091 keV levels of 208Pb are assigned spins of 1 and assuming 100% ground state branching the widths are calculated to be 31±3 and 17±2 eV respectively. It is suggested that the states in 207Pb and 209Bi arise from the weak coupling of a P12 neutron hole and an h92 proton respectively to one or the other of the 208Pb levels. The widths obtained in terms of gΓo2/Γ are 15±4 and 25±5 eV for the 7186 and 7206 keV levels of 207Pb and 24±5 and 30±5 for the levels of 209Bi respectively. These values are consistent with the weak-coupling suggestion.  相似文献   

14.
The difference in g-factors for the 61+ and 81+(πh922) states in 210Po has been measured as (g6 ? g8)g8 = 2.0 ± 0.7%. This result represents a small violation of additivity. A value of g8 = 0.909 ± 0.011, independent of g6, was also obtained.  相似文献   

15.
The (d, 3He) and (α, t) proton transfer reactions on 91Zr were studied at incident energies of 24.3 and 35.4 MeV, respectively. Angular distributions were measured from 6° to 50° (90Y) and 60° (92Nb). High detection efficiency and good energy resolution were obtained by using a magnetic spectrograph in connection with a multiwire proportional chamber. For the low-lying multiplet levels in both nuclei angular momentum transfers and spectroscopic factors were determined by DWBA analysis. In 92Nb the states at 0, 0.135, 0.29, 0.36 and the sum of the states at 0.48 and 0.50 MeV show typical l = 4 shapes. They belong to the (1g92π)(2d52ν) sextet. The corresponding multiplet in 90Y is weakly populated ( ≦ 20 μb/sr), and l = 4 shapes are found for the levels at 0.68, 0.78, 0.95, 1.05 and 1.30 MeV proving previous assignments. The members of the low-lying (2p12π)(2d52ν) doublets in 90Y and 92Nb exhibit a characteristic l = 1 angular shape. The levels at 1.42, 1.57, 1.64, 1.76 and 1.81 MeV in 90Y are excited both by l = 1 and l = 3 resulting from a strong mixing of the (2p32π)?1(2d52ν) and (1f52π)?1 (2d52ν) multiplets. Only the level at 2.03 MeV displays a pure l = 3 shape. From the spectroscopic information on the (2p12π)(2d52ν) and (1g92π)(2d52ν) multiplets in 90Y and 92Nb the g.s. configuration mixing in 91Zr is deduced.  相似文献   

16.
The reaction 12C(7Li, t)16O has been studied at E(7Li) = 34 MeV with the LASL tandem accelerator and QDDD magnetic spectrometer. Angular distributions to levels with Ex < 11 MeV have been obtained from 0° to 90°, including 0°. The results have been analyzed with finite-range distorted-wave Born approximation theory. The α-particle spectroscopic factors and reduced widths obtained are compared with those calculated with group theory (SU(3)) and other models. The analysis of data for the 7.1 and 9.6 MeV Jπ = 1? levels, which are of great importance in stellar helium buring, yields a ratio, R, of dimensionless reduced α-widths θ2a(7.1 MeV)θ2a(9.6 MeV) = 0.35b ± 0.13. The observed line width of the 9.6 MeV level (Γc.m. = 390 ± 60 keV) is less than the accepted value (Γc.m. = 510 ± 60 keV) and implies θ2a(9.6 MeV) ≈ 0.6. These results as well as data for the 6.92 MeV Jπ = 2+ and 10.35 MeV Jπ = 4+ “α-cluster” states indicate 0.09 < θ2a(7.1 MeV) < 0.33 with a mean value θ2a(7.1 MeV) = 0.14 ± 0.04. The implication for stellar helium burning is discussed.  相似文献   

17.
The quantum efficiency of fluorescence, Y, of the 4607.33 Å Sr line (1P1?1S0transition) was measured in four pre-mixed, laminar, shielded CO/N2O flames of about 2700 K, with different quantitative compositions at 1 atm. From these data, the specific quenching cross sections for O2, CO2, CO and N2 were found to be (152±20 Å2), (30±5 Å2), (49±8 Å2) and (16±3 Å2), respectively.  相似文献   

18.
Energy levels in 40Ca up to 10.2 MeV have been studied in the neutron pickup reaction 41Ca(τ, α)40Ca with 20 MeV bombarding energy. Thirty excited states have been identified and angular distributions have been measured in the interval from 5° to 40° by means of a split-pole magnetic spectrometer. The angular distributions together with DW calculations have been used to extract ln values and spectroscopic factors. The ln = 2 strength distribution for the f72d32?1 particle-hole levels is compared to the lp = 3 strength distribution from pr stripping data.  相似文献   

19.
The 58Ni(τ, α)57Ni reaction has been studied at 25 MeV incident energy. Angular distributions have been measured from 5° to 50° with a split-pole spectrometer up to 13.5 MeV excitation energy. A local zero-range DWBA analysis has been carried out, allowing l-assignments for about eighty levels, most of them previously unknown. An isospin-dependent potential has been used in the calculation of the neutron form factor for both T<and T> states, and the C2S values deduced using this procedure are compared to those obtained with the usual separation energy method. Analog states of eleven 57Co levels have been identified and the eventuality for isospin mixing in 57Ni has been discussed. A sum rule analysis has been carried out and energy centroids of hole states have been determined. About 60% of the 1d52and 2s12T< strengths and the full 1d32 and 1f72 hole strengths are observed. It is shown that the two excess neutrons in the 58Ni ground state mainly populate the 2p32, 1f52and 2p12 orbitals, whereas the occupancy number of the 1g92 subshell is found to be smaller than 0.1%. Some non-pickup angular distributions have also been observed and a CRC analysis assuming two-step processes in the (τ, α) reaction and weak-coupling wave functions for final states has been attempted. Assignments of Jπ values are proposed for four 57Ni levels, based on this analysis.  相似文献   

20.
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 f722andd32?2f722, configurations.  相似文献   

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