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1.
A perturbative classical monopole solution for the SO(3) gauge theory is constructed in the limit of small but non-vanishing Higgs potential. This corresponds to the limit μ22MW2 = λ ? 1, where μ equals the mass of the scalar particle and MW equals the mass of the intermediate vector particles. The monopole solution and mass are found to involve non-analytic functions of λ: γ and λ ln λ. The monopole mass Mm is calculated to order μ2MW as
Mm=e2Mw1+12μMw+12μ2M2wlnμMw+0.7071μ2M2w
.  相似文献   

2.
The near-ultraviolet and visible emission bands of the SbF molecule have been photographed at high dispersion and rotational analyses performed. The principal molecular constants (in cm?1) obtained for 121SbF and 123SbF are
X21: 121Be=0.2803; 123Be=0.2796;αe=1.93×10?3
a2: 121Be=0.2806; 123Be=0.2801;αe=1.87×10?3
B0+: 121B0=0.2800; 123B0=0.2791,
A0+: 121B0=0.2385; 123B0=0.2378,
A22: 121Be=0.2411; 123Be=0.2405;αe=1.65×10?3
A31: 121Be=0.2414; 123Be=0.2409;αe=1.70×10?3
  相似文献   

3.
The ratio of the scale parameter Λ in massless QCD defined on a lattice to the one in the continuum theory is determined by performing one-loop renormalization of the coupling constant. Our calculation method on a lattice directly relates Λlattice to the continuum one in the minimal subtraction scheme. The effect of incorporation of massless quarks depends on a parameter λ which is introduced to avoid trouble with fermions on a lattice. For λ=1, which is Wilson's value, the ratio previously calculated by Hasenfratz in the pure gauge theory is changed as follows:
Δα=1MOMΔlattice=83.5for pure SU(3) gauge theory;
Δα=1MOMΔlattice=105.7 for QCD with 3 flavors;
Δα=1MOMΔlattice=105.7 117.0 for QCD with 4 flavors.
Critical properties of the lattice QCD will also be discussed briefly.  相似文献   

4.
The color bond structure of a quark-antiquark system is extended, in the long-range approximation, self-consistently to the baryonic three-quark bond structure for SU(3)c and generally to the N-quark bond structure for SU(N)c. The universal (N-independent) mass square eigenvalues for massless quarks are
M2=(HN)2?2mρ2α=13N?3να+constant, να=0,1,2,…
.  相似文献   

5.
A quasiclassical formulation for mobility in extrinsic semiconductors is presented based on scattering from ionized impurity atoms. Quantum theory enters the otherwise classical Chapman-Enskog expansion of the Boltzmann equation through incorporation of the Thomas-Fermi interaction potential together with the Bom approximation for evaluation of scattering integrals. The following expression results for mobility μi, (cgs):
μi32?2nse3m122kBT321f(γ)
,
f(γ)=[(1+γ)eγE1(γ)?1]
, where ns is impurity concentration, m1 is effective mass, E1(γ) is the exponential integral, ? is dielectric constant and γ is dimensionless Thomas-Fermi energy. The structure of the dimensional factor in the preceding expression for μi agrees with previous expressions for this parameter.  相似文献   

6.
The sound velocities in GeS2 glass have been measured by means of ultrasonic interferometry as a function of temperature or pressure up to 1.8 kbar. The bulk modulus Ks = 117.6 kbar and shear modulus G = 60.60 kbar were obtained for GeS2 glass at 15°C and 1 atm. The temperature derivatives of both sound velocities and elastic moduli are negative :
(1?T)
p =
?1.54 × 10?4 kmsec
°C,
(1?T)
p =
?1.27× 10?4 kmsec
°C and
(?Ks?T)
p =
?1.27 × 10?2kbar°C
,
(?G?T)
p = ?1.23 × 10?2 kbar/°C,
(?Y?T)
p = ?2.93 × 10?2 their pressure derivatives are positive:
(1?P)
T = 4.43× 10?2km/kbar,
(1?P)
T =
0.633 × 10?2kmkbar
and (?Ks?P0)T=6.81,
(?G?P)T
= 1.03, (?Y?TT= 3.57. The Grüneisen parameter, γth= 0.298, and the second Grüneisen parameter, δs = 3.27, have also been calculated from these data. The elastic behavior of GeS2 glass has proved to be normal despite the structural similarity among the tetrahedrally coordinated SiO2, GeO2 and GeS2 glasses.  相似文献   

7.
A red-degraded band head, normally badly overlapped by the gamma system, A3Φ - X′ 3Δ, of zirconium oxide, appears in emission spectra of zirconium arcs and in absorption spectra of S-type stars and of frozen rare gas matrices containing zirconium. The emission band has been examined at high-resolution with the aid of separated zirconium isotopes. Identification of the band as 0-0 of a 1Π - X 1Σ+ system of zirconium oxide is confirmed by rotational analysis where the following constants (cm?1) are obtained for 90Zr16O:
B0′(R,P) = 0.40142 D0′(R,P) = 3.51 × 10?7
B0′(Q) = 0.40166 D0′(Q) =3.52 × 10?7
B0″ = 0.42263 D0″ =3.19 × 10?7
ν0 = 15383.81s
The Λ-type doubling in the 1Π state and the question of whether X 1Σ+ or X′ 3Δ is the true ground state of ZrO are discussed.  相似文献   

8.
The microwave spectrum of the molecular transient disulfur monoxide, S2O, has been reexamined and the microwave measurements have been extended into the millimeterwave region. From the present data, the following ground-state rotational constants and quartic distortion constants have been obtained (MHz):
A = 41915.44, B = 5059.07, C = 4507.19
δJ = 1.895 X 10?, δJK = ?3.192 X 10?2,δK = 1.197 X 100
δJ = 3.453 X 10?4 and δK = 1.223 X 10?2
The centrifugal distortion constants obtained from the rotational spectrum are used to discuss the vibrational spectrum of disulfur monoxide.  相似文献   

9.
The infrared spectrum of yttrium monoiodide has been excited in an electrodeless microwave discharge and explored between 2500 and 12 000cm?1 with a high-resolution Fourier transform spectrometer. A unique system is observed (ν00 = 9905.520 cm?1), which we attribute to a 1Π1Σ transition and an extensive analysis is made. Rovibrational constants are obtained for both states mainly from a simultaneous multiband fitting. This procedure is applied to the whole set of 2231 observed line wavenumbers in the 1-0, 0-0, and 0–1 bands, yielding a final weighted standard deviation of 0.0038 cm?1. Furthermore, a partial analysis of the 2-0 and 3-1 bands is performed. The following equilibrium constants are derived (cm?1):
ω′e=192.210 ω′ex′e=0.463
B′e=0.0399133 α′e=0.0001150
ω″e=215.815 ω″ex″e=0.514
B″e=0.0422163 α″e=0.0001125
High-order constants Dv and Hv are also calculated for the various vibrational levels (v′ = 0, 1, 2, 3; v″ = 0, 1).  相似文献   

10.
We have measured the wavelengths of the 3d52?2p32 and the 3d32-2p12 X-ray transitions in μ-24Mg, -28Si and -31P with the bent-crystal spectrometer at the SIN muon channel. The X-rays are measured relative to the wavelengths of the 84 keV and the 63 keV γ-rays of 170Tm and 169Yb which have recently been calibrated to about 1 ppm. The measured X-ray wavelengths λexp are compared with theoretical values λth, as obtained from QED calculations. The relative difference, averaged over all six measured transitions, is
λexpthλth = (2 ± 8) × 10?6
This result corresponds to a test of the vacuum polarization effect in QED of (0.6 ± 2.4) × 10?3. Assuming the QED calculations to be correct, we can use the result to put limits on additional muon-nucleon interactions (as required by gauge theories). If such an interaction is mediated by a scalar, isoscalar boson with a mass smaller than 1 MeV, the coupling constant is found to be
gNgμ = (?4 ± 17) × 10?9
Alternatively, we can deduce from our experiments the most accurate direct value to date for the negative muon mass,
mμ- = 105.65906(91) MeV
.  相似文献   

11.
Hollow-cathode discharges in the rare gases mixed with small amounts of H2 have been examined. Earlier results of Brault and Davis on the spectrum of ArH+ have been extended, and a new spectrum of KrH+ has been found. On the other hand, no emission spectra of HeH+, NeH+, or XeH+ were observed. Principal results for 84KrH+ are (in cm?1)
ωe=2494.7 Be=8.381
ωeχe=48.5 α=0.267
  相似文献   

12.
The q2 variation of the factor ?+(q2) in the decay K+π0e+ν has been studied using a sample of even detected in the CERN 1.1 m3 heavy-liquid bubble chamber. The data are consistent with a linear development ?+(q2)=?+(0) (1+λ+q/m2π) with λ+=0.027±0.008.  相似文献   

13.
14.
The transverse spin pair correlation function pxn=<SxmSxm+n>=<SxmSxm+n> is calculated exactly in the thermodynamic limit of the system described by the one-dimensional, isotropic, spin-12, XY Hamiltonian
H=?2Jl=1N(SxlSxl+1+SylSyl+1)
. It is found that at absolute zero temperature (T = 0), the correlation function ρxn for n ≥ 0 is given by
ρx2p=142π2pΠj=1p?14j24j2?12p?2jif n=2p
,
ρx2p+1142π2p+1Πj=1p4j24j2?12p+2jif n=2p+1
, where the plus sign applies when J is positive and the minus sign applies when J is negative. From these the asymptotic behavior as n → ∞ of |?xn| at T = 0 is derived to be xn| ~ an with a = 0.147088?. For finite temperatures, ρxn is calculated numerically. By using the results for ?xn, the transverse inverse correlation length and the wavenumber dependent transverse spin pair correlation function are also calculated exactly.  相似文献   

15.
The third order elastic constants of RbCl, determined by measurements of the static stress dependence of ultrasonic waves, are found to be (in units of 1012dynescm2)
C111 = ?6.71 ± 0.1 C123 = 0.05 ± 0.07
C112 =?0.18 ± 0.04 C144 = 0.11 ± 0.02
C166 =?0.17 ± 0.01 C456 = 0.4 ± 0.01
. The calculation of third order constants using a rigid ion Born model is briefly discussed, and results are compared to the measurements. The comparison qualitatively supports the model, but no quantitative evaluation of the repulsive interaction is possible.  相似文献   

16.
The rotational spectrum of methylene cyanide has been measured up to J = 62 and a total of 82 b-type transitions have been obtained. These data have been analyzed with a semirigid rotor Hamiltonian to give accurate rotational and centrifugal distortion constants. The rotational constants are (in MHz) A = 20882.7537 ≠ 0.017, B = 2942.3003. ≠ 0.0031, C = 2616.7225 ≠ 0.0031 The quartic centrifugal distortion constants are (in MHz)
ΔJ (1.855455 ≠ 0.014) x 10?3 ΔJK = (?6.79218 ≠ 0.027) x 10?2
ΔK (8.621628 ≠ 0.013) x 10?1 δJ = (4.892607 ≠ 0.016) x 10?4
δK = (6.7501 ≠ 0.29) x 10?3
The uncertainties are twice the standard deviations in the constants obtained from the least squares analysis, and represent approximately 95% confidence limits.  相似文献   

17.
It is shown that every spontaneous breaking of supersymmetry can be accomplished by means of a locally conserved supercurrent
εαβf+γ?, α, β, γ = 1, 2,
εαβ = 01?11
, where f+γ? is a massless field satisfying the Weyl Equation. For a given supercurrent jαβγ? the necessary condition that it will break spontaneously the supersymmetry is
jαβγ??jβαγ? ≠0.
It is shown that the anticommutation relations of the broken supercharges are not related to the energy-momentum vector.Similar procedure applied in case of a vector field is inconclusive.The extension of the Maisson and Reeh statement on the helicity of Goldstone fields is given.  相似文献   

18.
Last year Polyakov discovered the important role the trace anomaly plays in the relativistic string theory. This result means that one has to add counter terms to the string lagrangian
L=Lstring+CL1,
, where L1 contains a cosmological term and a term from the trace anomaly. In the conformal gauge we have
L1=LLiouville.
. We give a conventional GGRT treatment of this modified lagrangian for the bosonic string. Under the assumption that the exact quantization of Liouville's equation does not yield any additional anomalies, we show that relativistic invariance requires the constant C to be C = 26 ? D48π, in agreement with Polyakov's result. For D < 26 the string acquires longitudinal modes, and our calculations show explicitly how the longitudinal component of the string receives the degrees of freedom from the Liouville variable. Under the boundary conditions yielding the lowest value of the classical Liouville hamiltonian, the mass spectrum starts with a tachyon m2 = ?1α′, independent of D. The lowest-lying longitudinal excitation is m2 = 1α′. These results are semiclassical. It is shown that an exact quantization of Liouville's equation could remove the tachyon state when D < 26.  相似文献   

19.
The self-diffusion coefficients of 14C in NbCx single crystals have been measured as a function of composition in the temperature range 1900–2315 K, and can be represented by the expressions
D1C(NbC0.868) = (2.59?1.07+1.82) exp (?100.42 ± 2.2 kcalmolRT)cm2s
D1C(NbC0.834) = (7.44?4.14+9.36) exp (?105.0 ± 3.3 kcalmolRT)cm2s
D1C(NbC0.766) = (2.22?1.04+1.98) × 10?2exp (?76.02 ± 2.7 kcalmolRT)cm2s
The lower values of the activation energy and the pre-exponential term in NbC0.766 are attributed to a change in the path of C mass transport from that of an octahedral-tetrahedral-octahedral mechanism in NbC0.868 and NbC0.834 involving a C-metal divacancy mechanism. The effect of lattice geometry and the electronic charge distribution on the diffusion mechanism is also discussed.  相似文献   

20.
A rotational analysis of the satellite bands of the β system of ZrO gives the splittings in the triplet states. For the lowest triplet state X3Δ, these splittings are:
δF1,2 = 287.9 ± 0.1 cm?1,
δF2,3 = 337.6 ± 0.4 cm?1.
  相似文献   

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