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1.
A molecular beam resonance apparatus with electric quadrupole lenses asA- andB-fields and with superimposed parallel electric and magnetic transition-fields was used. Molecules in different rotational statesJ, m J are separated by theA-field. Spectra of molecules in different vibrational states are resolved by their different Starkeffect energies. By this means the following electric and magnetic properties of the molecule could be measured in the rotational stateJ=1 and vibrational statesv=0 and 1: The magnetic and electric dipole moment of the molecule, the scalar and the tensor nuclear dipole — dipole interactiond s andd T, the nuclear spinrotational interactionc F andc Rb, the nuclear quadrupole interactioneqQ, the nuclear magnetic moment μRb, the anisotropy of the diamagnetic susceptibility ξ, the anisotropy of the diamagnetic shielding of the external field by the electrons at the position of the nuclei σ. Using these quantities it was possible to calculate the quadrupole moment and a weighted quadrupole moment of the electronic charge distribution. The results are: (J=1,v=0) μel=8,5464 (17) debμ J/J=?29,79(2)x10?6 μ B d s/h=0,36(23) kHzd T/h=0,69(22)kHzc F/h=10,42(70) kHzc Rb/h=0,479 (48) kHz.eqQ Rb/h=?70,3410(26) MHzμ(1?σS)Rb=1,3474(5) μk⊥-ξ )=12(6)×10?30 erg/Gauß2⊥-σ∥)Rb=?3,8(2,1)×10?4⊥-σ )F=?2,6(3)×10?4  相似文献   

2.
Fe2SiS4(a = 12,407 A?, b = 7,198 A?, c = 5,812 A?, space group Pnma) has the olivine structure; the ferrous ions are located in two kinds of sites: one half in planes of mirror symmetry m, the other half in centers of symmetry. 1?.The magnetic study of this compound by means of magnetization measurements and Mössbauer effect, indicates from 127 K an antiferromagnetic arrangement along oy for the m sites, and an induced partial order of the same kind for the 1? sites. At 33 K, the Fe2+ spins in 1? sites are completely ordered and at the same time takes place a rearrangement of the magnetic structure. The observed complex model is analogous to that of Fe2GeS4, i.e. antiferromagnetic along 0x and ferrimagnetic along Oz.  相似文献   

3.
Starting with the definition of quaternion gauge theory, we have undertaken the study of SU(2) e ×SU(2) m ×U(1) e ×U(1) m in terms of the simultaneous existence of electric and magnetic charges along with their Yang-Mills counterparts. As such, we have developed the gauge theory in terms of four coupling constants associated with four-gauge symmetry SU(2) e ×SU(2) m ×U(1) e ×U(1) m . Accordingly, we have made an attempt to obtain the abelian and non-Abelian gauge structures for the particles carrying simultaneously the electric and magnetic charges (namely dyons). Starting from the Lagrangian density of two SU(2)×U(1) gauge theories responsible for the existence of electric and magnetic charges, we have discussed the consistent theory of spontaneous symmetry breaking and Higgs mechanism in order to generate the masses. From the symmetry breaking, we have generated the two electromagnetic fields, the two massive vector W ± and Z 0 bosons fields and the Higgs scalar fields.  相似文献   

4.
Correlations of the topological charge Q, the electric current J e, and the magnetic current J m in SU(2) lattice gauge theory in the maximal Abelian projection are investigated. It is found that the correlator 〈〈QJ eJm〉〉 is nonzero for a wide range of values of the bare charge. It is shown that: (i) the Abelian monopoles in the maximal Abelian projection are dyons which carry fluctuating electric charge; (ii) the sign of the electric charge e(x) coincides with that of the product of the monopole charge m(x) and the topological charge density Q(x). Pis’ma Zh. éksp. Teor. Fiz. 69, No. 3, 161–165 (10 February 1999) Published in English in the original Russian journal. Edited by Steve Torstveit.  相似文献   

5.
A model for high-spin/low-spin transitions in solids is discussed including the effect of low symmetry ligand fields and spin-orbit coupling. These interactions are required in the calculation of quadrupole splitting and magnetic susceptibility. In addition, the contribution from lattice vibrations is taken into account within the approximation of the Debye model. The recently observed entropy change at the transition temperature may be easily explained on this basis. The model is applied in a detailed numerical fit of the experimental data of [Fe(4,7-(CH3)2-phen)2(NCS)2] where phen = 1,10-phenanthroline. The compound may be characterized by the parameter values Δ1, = Δ2 = 400 cm?, λ = ?80 cm?1, J = 196 cm?1 (or Jtot = 205 cm?1) and N = 10 experimentally based Debye temperatures Θ1 = 140 K and Θh = 130 K have been employed.  相似文献   

6.
We study phenomenological consequences of the Standard Model extension by the new spin-1 fields with the internal quantum numbers of the electroweak Higgs doublets. We show, that there are at least three different classes of theories, all motivated by the hierarchy problem, which predict appearance of such vector weak-doublets not far from the weak scale. The common feature for all the models is the existence of an SUW(3) gauge extension of the weak SUW(2) group, which is broken down to the latter at some energy scale around TeV. The Higgs doublet then emerges as either a pseudo-Nambu-Goldstone boson of a global remnant of SUW(3), or as a symmetry partner of the true eaten-up Goldstone boson. In the third class, the Higgs is a scalar component of a high-dimensional SUW(3) gauge field. The common phenomenological feature of these theories is the existence of the electroweak doublet vectors (Z?,W?), which in contrast to well-known Z and W bosons posses only anomalous (magnetic moment type) couplings with ordinary light fermions. This fact leads to some unique signatures for their detection at the hadron colliders.  相似文献   

7.
The fundamental band of HD has been studied at room temperature and 0.6 atm pressure with a 48-m absorption path and a resolution of 0.01 cm?1. The frequencies of nine electric dipole and three electric quadrupole transitions were measured with an accuracy of 0.001 cm?1, and their analysis gives improved molecular parameters for the v = 0 and 1 states of HD. The intensities of the dipole transitions were measured in order to determine the v = 1-0 electric dipole transition moment. These measurements extend earlier experiments to higher J values, thus refining the determination of the rotational dependence of the transition moment.  相似文献   

8.
The 2ν3(A1) band of 12CD3F near 5.06 μm has been recorded with a resolution of 20–24 × 10?3 cm?1. The value of the parameter (αB ? αA) for this band was found to be very small and, therefore, the K structure of the R(J) and P(J) manifolds was unresolved for J < 15 and only partially resolved for larger J values. The band was analyzed using standard techniques and values for the following constants determined: ν0 = 1977.178(3) cm?1, B″ = 0.68216(9) cm?1, DJ = 1.10(30) × 10?6 cm?1, αB = (B″ ? B′) = 3.086(7) × 10?3 cm?1, and βJ = (DJ ? DJ) = ?3.24(11) × 10?7 cm?1. A value of αA = (A″ ? A′) = 2.90(5) × 10?3 cm?1 has been obtained through band contour simulations of the R(J) and P(J) multiplets.  相似文献   

9.
We present an analysis of static axially symmetric gauge fields for an arbitrary gauge group G. Two ansätze are considered. The full ansatz involves a total of 4d(d = dim G), the reduced ansatz only 2d functions of (?, z). Imposing self-duality is shown to reduce the problem to a sigma model in the curved two-dimensional (?, z) space over the coset spaces G?/G for the full, and G1/K for the reduced ansatz. G? is the complexification of G. 1 is a particular non-compact form of G, and K the local form-preserving symmetry group of the reduced ansatz. We give explicitly the Lax-pair type representations (linear scattering problem) of the sigma model, indicating that the standard methods available for certain non-linear two-dimensional problems can be used to generate solutions. Our procedure has the advantage that only real fields over a real manifold enter the analysis.  相似文献   

10.
The hyperfinestructure, Stark effekt and Zeeman effect of the TlF molecule have been measured with a molecular beam resonance apparatus. The apparatus uses electric four poles as deflecting fields and a homogeneous electric field parallel to a super-imposed magnetic field in the transition region. Electric dipole transitions withΔm J =±1,ΔJ=0 (J rotational quantum number) were measured in the following (v, J) states (v vibrational quantum number): (0,1), (1,1), (2,1) and (0,2) of the molecule205Tl19F and (0,1) of the molecule203Tl19F. For these five states the following interaction constants were determined: The magnetic (and the electric) dipolemoment of the molecule, the scalar and the tensor nuclear dipole-dipole interaction, the nuclear spin-rotational interactions, the anisotropy of the diamagnetic susceptibility ξ, the anisotropy of the diamagnetic shielding of the external field by the electrons at the position of the nuclei σ. From these quantities it was possible to calculate the quadrupole-moment of the electronic charge distribution. Furthermore, the dependence of the ratio of the isotopic electric dipolemoments on vibrational state was measured. A new method for determining the nuclear magnetic moments is described. The method consists of a molecular beam resonance apparatus with combined magnetic and electric transition fields and was used to measure the magnetic moments of the nuclei205Tl and19F. — On page 293 will be found a table of results.  相似文献   

11.
The two-loop corrections to the axial anomaly are calculated for a non-abelian gauge theory with fermions using both conventional and supersymmetric dimensional regularization. In both cases we find results consistent with the Adler-Bardeen theorem if we use non-anticommuting γ5 of 't Hooft and Veltman. Expectations (based on the supermultiplet structure of the anomalies) that there exists in N = 1 supersymmetric Yang-Mills theory an axial current J5 such that ?·J5 ~ β(g)FF? are discussed.  相似文献   

12.
Results from analysis of sub-Doppler laser-Stark spectra of 14NH3 obtained using a CO laser and an intracavity Stark cell are given. Over 1500 Lamb dips have been identified, associated with about 200 NH3 lines. The data are analyzed to determine relative frequencies between the laser lines and the NH3 lines. In favorable cases this can be done with an accuracy of 5–10 MHz. Analyses of a portion of the data yield the expression for the ground state dipole moment in Debye, μH(J, K) = 1.47182(30) + 1.654(190) × 10?4J(J + 1) ? 3.095(300) × 10?4K2.  相似文献   

13.
14.
We perform a variational calculation of the masses of glueballs of various spins and parities in SU(2) gauge theory. The quantum vacuum we use is generated by the lattice Monte Carlo technique. Our first results, obtained on medium sized lattices give m(0+) = (3.6 ± 0.35) Λmom, m(0? = (6.0 ± 1.0)Λmom, m(2+) = (6.5+1.8?1.1)Λmom, various mass upper bounds and information on glueball wave functions.  相似文献   

15.
An electric Molecular-Beam-Resonance-Spectrometer has been used to measure simultanously the Zeeman- and Starkeffect splitting of the hyperfinestructure of TlF. Electric fourpole lenses served as focusing and refocusing fields of the spectrometer. A homogenous magnetic field (Zeeman-Field) was superimposed to the electric field (Stark-Field) in the transition region of the apparatus. The observedΔm J =±1 -transitions were induced electrically. Completely resolved spectra of Tl205F19 in theJ=1 rotational, andυ=0 vibrational state have been measured. The obtained quantities are: The rotational magnetic momentμ J of Tl205F19 in the stateJ=1,υ=0, and the difference of the magnetic shielding (σ 1,±1?σ 1,0) of both nuclei as well as the difference of the molecular susceptibility (ξ 1,±1?ξ 1,0) in the states (J, m J)=(1,±1) and (J, mJ)=(1, 0). The sign of the rotational magnetic moment could be determined unambigously by the influence of offdiagonal matrix elements. The numerical values for Tl205F19 in the stateJ=1 andυ=0 are:μ J =?29,153(21) · 10?6 μ Bohr (σ 1,±1?σ 1,0)Tl=?0,002291 (33) (σ 1,±1?σ 1,0)F=?0,000206(9) (ξ 1,±1-ξ 1,0)=+3,02(15) · 10?30erg/Gauß2 The quantities in brackets are root-mean-square deviations in units of the last digit. From these data and the known values for the spin-rotational interaction constants a number of expressions are derived which characterise the electronic charge distribution in the molecule.  相似文献   

16.
The effect of the neutrino dipole magnetic moment on the properties of the muon is investigated within the standard model of electroweak interactions and a model based on the SU(2) L × SU(2) R × U(1) B-L gauge group (left-right model). In the case of the Dirac neutrino, muon decay through the channel µ?e ?γ is studied with allowance for the neutrino dipole magnetic moment. It is shown that, both in the standard model supplemented with an SU(2) L right-handed neutrino singlet and in the standard model featuring two doublets of Higgs fields, radiative muon decay is unobservable. In the left-right model, the contributions of diagrams associated with the neutrino dipole magnetic moment become significant only in the case of a mutual compensation of the contributions of diagrams involving the electromagnetic vertices of charged gauge bosons and singly charged Higgs bosons. At specific values of the parameters of the left-right model, one can then obtain an experimental upper limit on the branching fraction of this reaction. The contributions of the neutrino dipole magnetic moment to the muon anomalous magnetic moment are found for the Dirac and the Majorana neutrino. It is established that, both in the standard model and in the left-right model, values of the neutrino anomalous magnetic moment that are required for explaining the (g ? 2)µ anomaly are in excess of the theoretical predictions for this moment.  相似文献   

17.
The absolute intensities of the transitions 401III←000 and 411III←010 of CO2 have been measured from spectra obtained under high resolution. Both the vibration-rotation line intensities and the integrated band intensities are reported. The rotationless transition moment of 401III←000 is deduced and a vibration-rotation interaction factor F(m) = 1+(4.92×10?4)m+(4.4×10?7)m2 is determined. The values obtained are: SBand(401III←000) = (25.54±0.22)×10?5 cm?2atm(293 K)?1, |R000401III| = (1.87±0.02)×10?4D, and SBand(411III←010) = (1.83±0.13)×10?5 cm?2atm(293 K)?1.  相似文献   

18.
We construct the non-compact Calabi-Yau manifolds interpreted as the complex line bundles over the Hermitian symmetric spaces. These manifolds are the various generalizations of the complex line bundle over CPN−1. Imposing an F-term constraint on the line bundle over CPN−1, we obtain the line bundle over the complex quadric surface QN−2. On the other hand, when we promote the U(1) gauge symmetry in CPN−1 to the non-abelian gauge group U(M), the line bundle over the Grassmann manifold is obtained. We construct the non-compact Calabi-Yau manifolds with isometries of exceptional groups, which we have not discussed in the previous papers. Each of these manifolds contains the resolution parameter which controls the size of the base manifold, and the conical singularity appears when the parameter vanishes.  相似文献   

19.
NMR spectra of samples containing a mixture of hydrogen deuteride HD with pressure of about 80 atm and helium-3 with partial pressure of about 1 atm are analyzed. The ratio of the resonance frequencies of the nuclei, F(3He)/F(H2), is determined to be 0.761786594(2), which is equal to the magnetic moment of the helion (bound in a helium atom) in the units of the magnetic moment of a proton (bound in molecular hydrogen). The uncertainty of two digits in the last place corresponds to a relative error of ??[F(3He)/F(H2)] = 2.6 × 10?9. The use of the known calculated data on the shielding of nuclei in the helium-3 atom (??(3He) = 59924(2) × 10?9) and on the shielding of protons in hydrogen (??(H2) = 26288(2) × 10?9) yields a value of ??(3He)/?? p = ?0.761812217(3) for the free magnetic moment of the helion in the units of the proton magnetic moment.  相似文献   

20.
Theg J factors of the metastable states3 P 2 of88Sr and3 D 1,3 D 2,3 D 3, and1 D 2 of138Ba have been measured using the atomic-beam magnetic resonance method. The metastable states were populated by an electric discharge within the atomic-beam source. From the measurements of rf transitions between the Zeeman levels (m J =+1)?(m J =?1) we obtained:88Sr:g J (3 P 2) =1.501124(10)138Ba:g J (3 D 3)=1.3340823 (10)g J (3 D2)=1.1637406(11)g J (3 D 1)=0.4985751(13)g J (1 D2)=1.003 1449(10). The relativistic and diamagnetic corrections for theg J factor of the3 P 2 state of Sr have been calculated. With these and the Schwinger correction included we getg J (3 P 2)=1.501119(12).  相似文献   

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