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1.
E. Hagn  E. Zech 《Nuclear Physics A》1982,373(2):256-266
The magnetic hyperfine splitting vM=|gμNBHF/h| of 196mAu (jπ=12?; configuration ¦(π112(v132+)〉12?; T12 = 9.7 h) as dilute impurity in Ni has been determined with nuclear magnetic resonance on oriented nuclei as 96.0(2) MHz. With the known hyperfine field BHF = ?264.4(3.9) kG corrected for hyperfine anomalies the g-factor and magnetic moment of 196mAu are deduced to be |g| = 0.476(7) and |μ| = 5.72(8) μN. Taking into account the known magnetic properties of π12? and v132+ isomeric states in the neighbouring odd Pt, Au and Hg nuclei the structure of the 12? state is discussed.  相似文献   

2.
The atomic beam magnetic resonance method combined with laser-induced state- and isotopeselective detection of metastable atoms has been used to investigate the hyperfine structure of the 2D ground multiplet in 175Lu and 176Lu. The analysis of the data yields not only accurate values for the hyperfine interaction constants, the nuclear magnetic dipole moment of 175Lu, and the electronic gJ, factors, but also the first directly measured value of the nuclear magnetic dipole moment of the low abundant isotope 176Lu: μI(176Lu) = 3.1692 (45)μN (corrected for diamagnetic shielding). The spectroscopic quadrupole moment of 176Lu was calculated from the ratio of the B-factors and the quadrupole moment of 175Lu: Qs(176Lu) = 4.92 (3) b. Moreover, the magnetic hyperfine anomalies for the isotopic chain 175,176,176m,177Lu were determined. A quadrupole hyperfine anomaly between 175Lu and 176Lu was not found when comparing the ratio of the B-factors in the states 2D32and2D52. From a comparison of the quadrupole moment of 175Lu obtained from the hyperfine structure data and the quadrupole moment measured in muonic lutetium atoms semi-empirical Sternheimer shielding factors could be estimated.  相似文献   

3.
The magnetoresistance in (SN)x single crystals is composed of the normal positive and negative components. The former increases in proportion to the square of the magnetic field B2. The latter is remarkable at temperatures below 4.2 K and saturates at relatively low magnetic field (? 30 kG). The coefficient S(=limB→0{??(δρρ0)?B2}) of this negative magnetoresitance shows features similar to those of semiconductors with Toyozawa's theory. These results of negative magnetoresistance are explained in terms of carrier scattering by localized magnetic moments.  相似文献   

4.
R. Eder  E. Hagn  E. Zech 《Nuclear Physics A》1984,413(2):247-254
The magnetic hyperfine splitting νM = |NBHF/h| of 175Ta (Jπ = 72+; T12 = 10.5 h) in Fe has been measured with the technique of nuclear magnetic resonance on oriented nuclei as 320.4(1) MHz. With the known hyperfine field BHF(TaFe) = ?648(13)kG the magnetic moment of the 72+[404] ground state of 175Ta is deduced to be ¦μ¦ = 2.27(5)μN.  相似文献   

5.
The magnetic hyperfine splitting νM = |NBHF/h| of 193mAu (jπ = 112?, E = 290 keV; T12 = 3.9 s) as a dilute impurity in Ni has been measured with nuclear magnetic resonance on oriented nuclei as 226.4(2) MHz. With the known hyperfine field BHF = ?264.4(3.9) kG corrected for hyperfine anomalies the g-factor and magnetic moment of 193mAu are deduced to be |g| = 1.123(17) and |μ| = 6.18(9) μN.  相似文献   

6.
Theory of negative magnetoresistance in two-dimensional systems due to delocalization of electrons by magnetic field by Hikami, Larkin, and Nagoaka is extended to the case of three-dimension. The increase in conductivity by magnetic field is independent of the direction of the current relative to that of the magnetic field, and is proportional to H2τ?32, τ? being energy relaxation time of electrons, when the magnetic field H is small. If τ? is large enough at low temperature and H is not too small, it is independent of the parameter characterizing the system, and is of the form 0.918?H mho cm?1 (H in kOe).  相似文献   

7.
The branching ratios are calculated for 11ΛB decay to the 11C ground and excited states below 8 MeV for two possible spin values of 11ΛB. It is found that the decay rate to the 11C state at E = 6.48 MeV is comparable in magnitude to that leading to the 11C ground state if J(11ΛB) = 52 is assumed. This result, unlike the branching ratios calculated for the J(11ΛB) = 72 case, is in accord with experiment and lends support to the assumption that J = 52 holds for 11ΛB. The necessity of the reinterpretation of some of the so-called 13ΛC events in terms of 11ΛB → π? + 11C1 is indicated.  相似文献   

8.
Polarized isomeric 24Nam(T12 = 20 ms, Iπ = 1+) nuclei were produced by capture of polarized thermal neutrons in a NaF single crystal at room temperature. The asymmetric β-decay radition of 24Nam was used to detect nuclear magnetic resonance signals yielding the magnetic moment |μ(24Nam)| = 1.930 (3) n.m. (uncorrected).  相似文献   

9.
A theoretical model used to describe the B′3Σu? and B3Πg states of N2 is presented. Using recently acquired high resolution spectra of the B′3Σu? → B3Πg (0-0) band, rotational energy levels of the v = 0 vibrational levels of these two states are generated with this model. These levels are in excellent agreement with those obtained using a combination differences technique. The precision of the model generated levels is 0.01 cm?1. The previously unpublished rotational levels of Dieke and Heath for the A3Σu+, B3Πg and C3Πu states are referenced to the N2X1Σg+ (v = 0, J = 0) ground level and tabulated here. Estimates of the precision of their work are made.  相似文献   

10.
The magnetic moment of the 132+ state in 207Po was determined to be μ = ?0.910 ± 0.014 n.m. An analysis of this value and other known moments of i132 neutron states around 208Pb supports the existence of a mesonic contribution of at least ?0.3 n.m. to the moment.  相似文献   

11.
The binding energies of the ΛΛ hypernuclei 10ΛΛBe and 6ΛΛHe are calculated variationally with a 2α + 2Λ and with an α + 2Λ model, respectively. For 10ΛΛBe the integrations were made with Monte Carlo techniques while for 6ΛΛHe direct numerical methods were used. A wide range of phenomenological ΛΛ potentials based on meson-exchange models was considered. An approximately universal linear relation between the calculated values of BΛΛ(10ΛΛBe) and of BΛΛ(6ΛΛHe) is obtained. For the experimental value of BΛΛ(10ΛΛBe) = 17.7 ± 0.1 MeV this relation predicts a much too small value of BΛΛ(6ΛΛHe), well below the lower limit of the quoted experimental value of 10.9 ± 0.6 MeV. For ΛΛ potentials with repulsive cores the relations, for a given BΛΛ(10ΛΛBe), between the low-energy ΛΛ scattering parameters a, r0 and the intrinsic range b are both approximately universal and independent of the detailed potential shape. For the experimental value of BΛΛ(10ΛΛBe) the preferred values are 2.5 ? ?a ? 3.5 fm, 2.6 ? r0 ? 3.1 fm. The large and negative values of a correspond to conditions not too far from a bound 1S0 ΛΛ state and could indicate a 6-quark dibaryon state with the same quantum numbers and above the ΛΛ threshold.  相似文献   

12.
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   

13.
14.
The microwave spectrum of MnO3F has been remeasured and several corrections and new results have been obtained: B0 = 4129.141 MHz, DJ = 1.12 kHz, DJK = 1.87 kHz; α3B = 8.622, α5B = ? 11.994, α6B = 6.042, |q5| = 16.005, and |q6| = 8.456 MHz.  相似文献   

15.
The vibration-rotation transitions for v = 1 ← 0 of NO (2Π12) have been studied by using the technique of laser magnetic resonance spectroscopy. Five magnetic resonance lines are observed with three CO laser lines in the range from 1859 to 1886 cm?1. From these, three zero-field transition frequencies, v = 1 ← 0; R(32), P(72), and P(92) are obtained with an accuracy of ±0.0007 cm?1. The molecular constants which have been determined by borrowing centrifugal constants from a previous infrared work are B021 = 1.72004 ± 0.00006 cm?1, B121 = 1.70212 ± 0.00010 cm?1, and G(v = 1) ? G(v = 0) (for 2Π12) = 1875.8470 ± 0.0007 cm?1.  相似文献   

16.
A rotational assignment of approximately 80 lines with Ka′ = 0, 1, 2, 3, and 4 has been made of the 593 nm 2A12B2 band of NO2 using cw dye laser excitation and microwave optical double-resonance spectroscopy. Rotational constants for the 2B2 state were obtained as A = 8.52 cm?1, B = 0.458 cm?1, and C = 0.388 cm?1. Spin splittings for the Ka′ = 0 excited state levels fit a simple symmetric top formula and give (?bb + ?cc)2 = ?0.0483 cm?1. Spin splittings for Ka′ = 1 (N′ even) are irregular and are shown to change sign between N′ = 6 and 8. Assuming that the large inertial defect of 4.66 amu Å2 arises solely from A, a structure for the 2B2 state is obtained which gives r (NO) = 1.35 A? and an ONO angle of 105°. Alternatively, weighting the three rotational constants equally gives r = 1.29 A? and θ = 118°.  相似文献   

17.
J. Nag  M.K. Pal 《Nuclear Physics A》1981,371(3):393-404
The effect of core polarization on the magnetic moment is studied for odd-mass nuclei around N = 50: 85, 87Kr, 87, 89Sr, 91Zr and89Y. The calculation is done in the framework of the modified Tamm-Dancoff approximation (MTDA). The ground-state wave function is calculated using the configuration space of p?f$?and ?dg$?shells. The core polarization correction to the magnetic moment is considerable for all the nuclei, except 89Y, and it depends upon the particular form of the interaction. For 89Y the last odd proton is in the p12 level and the smallness of the correction is supported by the observed value of the magnetic moment.  相似文献   

18.
We have obtained a least upper bound, kBTc ? c(μ1, t)A, on the critical temperature Tc of an isotropic superconductor with paramagnetic impurities described by the scattering matrix t for fixed values of μ1. We have also obtained the corresponding optimal spectrum α2F(m) = Aδ[ω?d(μ1, A]. The numerical results for the functions c(μ1, t) and d(μ1, t) are presented for α1 = 0.1 and 0.16 in the form of universal curves representing c(μ1, t) and d(μ1, t) as functions of the reduced impurity concentration t = t/A. We have also established an upper limit to the reduced critical concentration tcrit for an arbitrary shape of α2F(ω)1.  相似文献   

19.
Absolute extinction coefficient and oscillator strength of pyridine, pyrimidine, pyrazine, and s-triazine were recorded with moderate resolution in the region of 3.5–9.5 eV. Analogous to 1A1g1B2u, 1B1u, 1E1u π → π1 transitions of benzene, several n → π1 and Rydberg transitions are presented and discussed.  相似文献   

20.
An isomeric level in 107Cd at 845 keV populated by the reactions 107Ag(p, n), 106Cd(d, p) and 104Pd(α, n) has been observed. The half-life of this state is T12 = 77(7) ns, and the spin and parity are Iπ = 112?. The magnetic moment has been determined by the pulsed beam time-differential perturbed angular distribution method (DPAD) to be μ = ?1.012(12) n.m.  相似文献   

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