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1.
The magnetic dipole interaction of the 150 keV state of177Lu in an environment of metallic ytterbium has been investigated by time-differential perturbed angular correlation experiments. The measurements were performed in an external magnetic field of 0.4 T at room temperature. Two independent measurements at different - cascades give the same Larmor precession frequency. From the weighted average the magnetic dipole moment of the 150 keV state is derived as =+5.5(3) K. From the angular correlation coefficient A22=–0.042(7) of the (139–150) keV - cascade the mixing ratio =+0.21(4) is deduced. The coefficient A22=+0.015(7) of the (1080–150) keV - cascade yields the mixing ratio =+0.08(4).  相似文献   

2.
The magnetic dipole interaction of the 57 keV state of143Pr in an environment of metallic cerium and in an aqueous solution of Ce(NO3)3 has been investigated by time-differential perturbed angular correlation experiments. The measurements were performed in external magnetic fields between 0.94 T and 2.24 T and at temperatures between 77 K and 1200 K. From the temperature dependence of the observed spin rotation the ionicity of the Pr ion is determined as Pr4+ in the Ce(NO3)3 and as Pr3+ in Ce metal in the intermediate nuclear state. The magnetic dipole moment of the 57 keV state is derived as = +(3.4±0.1)K. From the room temperature relaxation constants 2 = (0.19±0.03)109s–1 for Ce(NO3)3 and 2= (0.07±0.02)109s–1 for Ce metal the correlation times J = (3.8±0.7)10–13s and J = (1.4±0.4)10–13s respectively are deduced. The angular correlation coefficientA 2=+0.17±0.02 is in good agreement with the result of a decoupling experiment.  相似文献   

3.
Temperature dependence of the angular distribution anisotropy of the 212·0 keV gamma-ray following the decay of153Tb oriented in a gadolinium host was measured at temperatures from 16 to 70 mK. Magnetic dipole hyperfine splitting parameter a0 for153Tb(Gd) and magnetic dipole moment of the153Tb ground state were estimated to be ¦a 0¦1·2×10–5 eV and ¦¦3·1 nuclear magnetons, respectively.Authors are indebted to Dr. N. A. Lebedev, Yu. V. Yushkewich and the staff of the JINR synchrocyclotron for the preparation of the153Tb activity. The participation of Ing. L. Mare, J. Ferencei and S. I. Antonov in the measurements is also acknowledged.  相似文献   

4.
The sign of the nuclear magnetic dipole moment of the ground state of122I has been determined to be positive using a novel experimental technique. The technique investigates the asymmetry of positron emission by detecting the 511 keV gamma-rays produced on the annihilation of the positrons. The method would appear to have general validity for studying the sign of the magnetic moment in other cases where theβ + decay is relatively simple.  相似文献   

5.
We study magnetic dipole moments of right-handed neutrinos in a keV neutrino dark matter model. This model is a simple extension of the standard model with only right-handed neutrinos and a pair of charged particles added. One of the right-handed neutrinos is the candidate of dark matter with a keV mass. Some bounds on the dark matter magnetic dipole moment and model parameters are obtained from cosmological observations.  相似文献   

6.
H. Zmora  M. Blau  S. Ofer 《Nuclear Physics A》1969,130(3):541-544
The magnetic moment of the 344 keV level of 152Gd was determined from measurements of the rotations of the angular correlations of γ-γ cascades involving this level in the magnetic hyperfine field of Gd metal. The value found for gτ is (2.43±0.22)·10−11 sec.. Taking τ = (7.6±1.3)·10−11 sec, a value of 0.32±0.06 was derived for the gyromagnetic ratio of this level.  相似文献   

7.
《Physics letters. [Part B]》1987,191(3):304-308
We examine mechanisms for producing neutrino magnetic moments from a wide class of particle theories which are extensions of the standard model. We show that it is difficult to naturally obtain a moment greater than ∼ 10−2 electron Bohr magnetons. Thus models of phenomena requiring moments of order ∼ 10−10 magnetons, such as those proposed as a resolution to the solar neutrino puzzle, are in conflict with current perceptions in particle physics.  相似文献   

8.
在推导出介质的极化强度与磁化强度的坐标变换公式的基础上,分析导出了运动介质的电偶极矩与磁矩.  相似文献   

9.
The Larmor precession of the 1,307 keV 2 ns state in69As in an external magnetic field of 2 T has been observed in a time integral perturbed angular distribution experiment. The deducedg-factor ofg=1.05±0.13 confirms the rather pureg 9/2 proton structure of this state on which a triaxial rotational aligned band is built.  相似文献   

10.
The g-factor of the 308 keV 2+ state in48V has been measured by means of the time differential perturbed angular correlation technique, following the implantation of48Cr activity into ferromagnetic iron in the reaction46Ti(,2n)48Cr. We obtained g = 0.222(8) and a substitutional fraction of f1>80%.  相似文献   

11.
The ground state g-factor for 55Co has been measured as ¦g¦= 1.378±0.001 by the technique of nuclear magnetic resonance on oriented nuclei. The temperature dependence of γ-ray anisotropy in the 55Fe daughter decay determines both the 1408 keV level spin and the 55Co ground state spin to be 72, and yields values of mixing ratios in the 1037 keV β-transition and the 477 keV γ-transition. The configuration mixing model is used to discuss 1f72 moment systematics.  相似文献   

12.
We demonstrate via first-principle calculations based on the density functional theory that the magnetic moment of a helium atom under a given magnetic field has a positive correlation with the electric dipole moment when an external electric field is applied to the system. Our calculation shows that the enhancement of the magnetic moment is significant due to the reduction of the tripletsinglet splitting. We argue that this finding can be generalized to organic molecules, especially to macromol...  相似文献   

13.
The quadrupole moment of the 535 keV 32? state of 133La has been derived from a time-differential perturbed angular correlation measurement in an environment of La metal. The effective electric gradient is known from a nuclear quadrupole resonance measurement with the ground state of 139La. The result Q = 0.35 ± 0.03 b does not confirm a proposed shape isomerism.  相似文献   

14.
运用MOLPRO软件,采用基组6-31G,6-31G(d),6-31G(2d,3f),aug-cc-pv5z, 方法HF(Hartree-Fock)、CASSCF(完全活性空间自洽场)和MRCI(多参考组态相互作用),计算了CO的基态 的偶极矩随核间距变化的12条曲线,与基于实验光谱数据的偶极矩在平衡位置的值以及在平衡位置的斜率进行了比较,结果表明,采用MRCI方法,aug-cc-pv5z基组的偶极矩曲线最为准确.平衡位置斜率的偏差小于1%.接着采用MRCI方法,aug-cc-pv5z基组计算得到了CO基态的势能曲线,进而通过求解核的薛定谔方程得到振动能级以及分子力常数,分子力常数与实验值符合的很好.  相似文献   

15.
The magnetic moment of the 828 keV level in 115In was found to be 0.80 ± 0.14 μN by measuring the γ-γ integral angular correlation perturbed by an external magnetic field. Several assumptions concerning the nature of the state investigated have been discussed.  相似文献   

16.
运用MOLPRO软件,采用基组6-31G,6-31G(d),6-31G(2d,3f),aug-cc-pv5z,方法HF(Hartree-Fock)、CASSCF(完全活性空间自洽场)和MRCI(多参考组态相互作用),计算了CO的基态X1Σ+的偶极矩随核间距变化的12条曲线,与基于实验光谱数据的偶极矩在平衡位置的值以及在平衡位置的斜率进行了比较,结果表明,采用MRCI方法,aug-cc-pv5z基组的偶极矩曲线最为准确.平衡位置斜率的偏差小于1%.接着采用MRCI方法,aug-cc-pv5z基组计算得到了CO基态的势能曲线,进而通过求解核的薛定谔方程得到振动能级以及分子力常数,分子力常数与实验值符合的很好.  相似文献   

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The electric dipole moment of the FO radical (2Π32) has been directly measured by observing its saturated absorption laser magnetic resonance spectrum (v = 1 ← 0) in the presence of a moderate electric field. The resulting dipole moment [μ(v = 0) = 0.0043(4) D, μ(v = 1) = 0.0267(9) D] is extremely small, and shows a large relative change with vibrational state. The sign of the dipole moment is the same for the two vibrational states. Previous failures to detect microwave or gas phase EPR spectra of FO are fully explained by this small dipole moment.  相似文献   

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