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1.
A new model of radiative -meson decays of vector mesons in the chiral bag model is proposed. The quark--meson interaction has the form of a pseudoscalar coupling and is located on the bag surface. The vector meson decay width depends on the quark masses, the -meson decay constant, the radius of the bag, and the free parameter Z2, which specifies the disappearance of the bag during the decay. The obtained results for the -and p-decay widths are in satisfactory agreement with the experiment.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 71–76, February, 1988.  相似文献   

2.
The meson wave function in the spinor stronginteraction theory is uniquely normalized on dimensionalgrounds, thus bypassing the fundamental problems in thenormalization of Klein-Gordon (KG) and Bethe-Salpeter amplitudes for mesons. While the KG amplitudeis proportional to 1/E, the present meson wavefunction is not and is thus flavor-independent. Theconfinement term is inactive for free mesons, but isactivated when interacting with another hadron or chargedlepton. The theory is applied to the strong decay of atwo-quark vector meson into two pseudoscalar mesons V PP. The so-obtained and estimated decay rates are consistent with data, as are the ratios ofthese rates to the corresponding radiative decay V P rates. These decay rates indicate apossible connection of the strong quark-quark couplings with the electromagnetic coupling alpha vias = 1/4 = 0.2923.Contrary to the standard electroweak model (SM), theelectromagnetic and weak couplings are detached fromeach other in connection with the absence of Higgs bosons,without altering the main results of the SM.  相似文献   

3.
Leptonic and semileptonic decays of pseudoscalar mesons are considered. The functional dependence of the weak form factors on the wave functions of the (q1¯q2) system is found. Numerical values of the coefficients and (for , K, D, and F mesons) determining the interquark potential are obtained. Within the framework of the Coulomb and oscillator models, the probability of semileptonic decays of D and F mesons is found. For D mesons, comparison with experiment is undertaken. Agreement with experiment is observed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 19–23, March, 1982.  相似文献   

4.
The paper considers the processes of formation of pseudoscalar mesons by the interaction of an antineutrino with a leptonv ll K, , K.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 139–143, August, 1974.  相似文献   

5.
The possible presence of hairpin diagrams is analyzed in th model-independent quark-diagram scheme for two-body decays of charmed mesons. Current experimental data do not require the presence of hairpin diagrams inDVP (V: vector meson,P: pseudoscalar meson), in accordance with the OZI rule. However, there is a possible indication that they are important in the decay ofDPP. The measurement ofD s + + is crucial to test the mechanism of hairpin diagrams.  相似文献   

6.
A simple quark pair creation model is introduced to study exclusive decays of {c_J} into baryon-antibaryon pairs. With this simple model, some exclusive decay processes, for example, {c0} B¯ (B = ,0,-) are investigated and their decay widths are evaluated by inclusion of the properties of outgoing baryons, and the results show that the strengthened decay channels {c_J} ¯(J = 0, 2) are easily understood by considering only the color singlet contribution of P-wave charmonium.  相似文献   

7.
A chiral Lagrangian for massive pseudoscalar mesons is derived from the QCD-generating functional by the chiral bosonization method. The low energy region in the fermionic integral where chiral noninvariant quark fluctuations dominate, is described by two mass parameters — an invariant cutoff and a spectral asymmetry M related to the gluon and quark condensates.  相似文献   

8.
The collinear production of a vector meson is considered in the scattering of pseudoscalar mesons on baryons. Relations between the experimental quantities, following from the symmetry [SU(3) SU(3)]coll, are obtained.On leave from the Nuclear Research Institute of the Czechoslovak Academy of Sciences, e.  相似文献   

9.
The differential cross-section is given for the electromagnetic scattering of polarized relativistic electrons on polarized nucleons. The finite size of each particle is taken into account by means of two form-factors. The effect of the possible non-punctiform structure of the electron on the polarization effects in scattering is discussed. It is shown that the internal structure of the anomalous magnetic moment of the electron would show itself in the cross-section by terms depending on the transversal polarization of the incident electrons.
. . . , , .


Summary of results of a diploma-thesis for the degree of graduate physicist.

In conclusion the author wishes to express his sincere gratitude to prof. V. Votruba and J. Kvasnica for suggesting this problem, for helpful discussions and valuable advice.  相似文献   

10.
The spinor strong interaction theory recentlydeveloped is applied to the radiative decay of atwo-quark vector meson into pseudoscalar meson V P. Expression of the decay rate isderived in this first-principle theory without assumptionand free parameter. The ratio (D*0 D0)/(D*+ D+) is correctly predicted. Theorders of magnitude of the radiative decay rates of B*,D*, K*, and estimated from this expression areconsistent with data. Very fast mesons have a smallersize then do mesons at rest, similar to Lorentzcontraction in laboratory space.  相似文献   

11.
The change in integrated intensity of the (200) reflections of a solid solution during the formation of G.P. zones was measured and compared with the change in the character of the diffuse streaks corresponding to them. It was found that the. formation of G.P. zones does not lead to a decrease in primary extinction despite the great changes in the distribution of the copper atoms. It was shown that the formation of a precipitate accompanied by the formation of crystallographically incoherent boundaries greatly decreases the primary extinction.
. II. 1-u 4%: [. . ]
(200) . . , . , . . , . , , , .
  相似文献   

12.
The method of sliding photomultipliers was used to study the connection between two forms of the positive column in oxygen — the so-called low-gradientT-form and the highgradientH-form — and the presence of moving striations in the positive column. It was shown that in theT-form of a positive column striations are always present which move from the cathode to anode with a velocity of several thousand metres/sec. The highgradient form of theH-positive column, on the other hand, is not striated. The non-single-valuedness of the value of the longitudinal electric field in a discharge in oxygen is thus explained by the presence or absence of phenomena of a time variable character.
— - H - — . , - , /. , , . , , , .
  相似文献   

13.
The s-wave pion scattering amplitude is analysed with the aim to clarify the mass spectrum of scalar mesons and to find evidence of lightest glueball. The S-matrix and K¯K coupled channel formalism is used. The existence of scalar mesons S* and is implied by the data. The production K¯K and the elastic K¯KK¯K coupled amplitudes are predicted from the scattering data. The couplings c f S* to and K¯K states are determined.  相似文献   

14.
A new method is proposed for calculating the energy in certain special points of the Brillouin zone. The wave functions of valence and conduction electrons are given in the form of the linear combination of plane waves and the orthogonality condition of these functions to the wave functions of lower states is replaced by the repulsive potential. The practical application of this very simple method is illustrated on the energy spectrum of silicon in the centre of the Brillouin zone. It is proved that the results are comparable with some other methods, e. g. the orthogonalized plane-wave method.
. . . , , .


The basic thesis of this paper, together with concrete calculation of the energy spectrum of diamond, was delivered at the Czechoslovak-Polish conference in Sopoty in November 1956.

In conclusion the autor would like to thank K. Trnková for carrying out the numerical calculations.  相似文献   

15.
A study is made of the Shockley surface states in a linear chain of equal atoms, joined by alternately strong bonds. If the simple MO LCAO method is used, which considers the exchange integrals between nearest neighbours and next nearest neighbours, we get the surface states for a semi-infinite chain if the stronger bond is interrupted. The connection between Shockley and Tamm surface states is shown and the hypothesis is put forward that the condition for the existence of Shockley surface states has a generally simple physical interpretation, the validity of which is proved on the models of a semi-infinite crystal studied up to now.
, . MO LCAO, , , . , , , .
  相似文献   

16.
17.
18.
The paper describes microscopic investigation into the spectral distribution of photo-luminescence and its polarization on hexagonal ZnS monocrystals in relation to the structural defects of such crystals. These observations, as well as birefringent observations, show that the values of the birefringence and the degree of polarization in different stripes of the same crystal are the same within the limits of observational errors.
ZnS: Cu
ZnS . , , , .


In conclusion the author would like to thank K. Pátek, L. Souková and M. Mokonová for providing the monocrystals and for fruitful discussions.  相似文献   

19.
20.
The width of S-wave quarkonium decays (c, b ; and J/, Y e+e) are calculated using the quasipotential approach. The nontrivial dependence of decay amplitude on relative quark momentum is considered. It is shown that relativistic corrections reach values of 30–50% in the processes studied.Samara State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 46–53, May, 1995.  相似文献   

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