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1.
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   

2.
We study the Sine-Gordon field theory at 2=8. We prove that the theory is renormalizable but not superrenormalizable and we show how the perturbative renormalization procedure works in this case where the interaction is not polynomial. To go beyond the perturbative results we investigate the -functional equation for this theory and discuss in what sense at 2=8 the theory is lacking the asymptotic freedom and how it is asymptotic free for 2<8 in a appropriate region of the coupling constants.  相似文献   

3.
The possible ways of drawing of the intensity of the S0 T* transition in the chlorobenzene molecule are investigated. The effective spin-orbit coupling of either S* or S* states with the T* state leads to the out-of-plane polarized component of phosphorescence in the chlorobenzene. The in-plane polarized component cannot be explained by the mechanism under consideration — by drawing of intensity of the S0 S0* transitions through spin-orbit coupling of first order.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 134–138, August, 1974.  相似文献   

4.
    
In this paper we present the results of a search for the charmed strange baryon c + in the final states 0++K and ++. The experiment was performed using the magnetic spectrometer BIS-2 with a hydrogen target located in the neutron beam of the Serpukhov accelerator. A narrow peak in the 0++K state is observed at a mass of 2440 and possibly also of 2310 MeV/c2, corresponding to signals for the c + 0++K and c + 0++K (0 0) decays respectively. The statistics obtained for the ++ state is too low to make any conclusion.We are grateful to K. Hiller, F. Mandl, M. Markytan and J.MacNaughton for useful discussions and valuable remarks.  相似文献   

5.
An expression for the decay rate (0 ) has been derived in the frameworkof the spinor strong interaction theory, a first-principles strong interaction theoryproposed some years ago as an alternative to low-energy QCD. The startingpoint is the SO(3) gauge-invariant action for two quark mesons which has beensuccessful in accounting for confinement, + + , e+, and 0 e+, nonexistenceof the Higgs boson, and other low-energy mesonic phenomena. The quasi-four-quarkmeson equations developed for the decay of a vector meson into twopseudoscalar mesons V PP has been taken over here to apply to P(0) VV(+ ) (plus + and which annihilate each other). This mechanismin principle agrees with that of the assumption of vector meson dominance inthe literature. It, together with the effect of form factors, arises naturally in theformalism and need not be assumed. Equations for the perturbed vector mesonwave functions cannot be simply solved and an assumption has been made toobtain an estimate of their magnitude. Together with a constant associated withthe strong coupling obtained earlier from V() PP(K+K), the estimated decayrate is 19.2 eV, in order-of-magnitude agreement with data (7.74 eV).  相似文献   

6.
Using scattering data, the integrated cross-section for p¯p+, and unitarity, we derive upper bounds to the differential cross-section for p¯p+ . Comparison with experimental data shows that in general the bounds are several times larger than the measured value, but that at certain points this factor is only about two or three.Presented at the Symposium on Hadron-Hadron Scattering at High Energies, Liblice, Czechoslovakia, June 16–21, 1975.I would like to thank Dr. A. K.Common for useful discussions and collaboration in the early stages of this work.  相似文献   

7.
A heuristic model for deriving the anomalous magnetic moment of the electron is presented. A term /2 – 0.327(/)2 is deduced, in better agreement with experiment than is the QED derivation of /2 – 0.328(/)2. The result is strengthened by the recent non-QED account of the Lamb shift by Yu and Sachs.  相似文献   

8.
We investigate the continuum three-pion problem within a relativistic three-body model that takes into account the S andP waves. The dynamical input of the two-body subsystem is given by separable potentials, which yield a good fit to the scattering data and resonance parameters up to a two-body invariant mass of 900MeV. We introduce a parameter expressing the ambiguity in the reduction of a fully relativistic theory to a three-dimensional one. The masses and widths of the ,a 1(1260), and (1300) mesons, which decay predominantly into three pions, are reasonably well described by our model. Theh 1(1170) meson, however, which also decays into three pions, cannot be explained as a three-pion resonance. Some Argand diagrams are shown in those channels where resonances exist.  相似文献   

9.
We report an experimental and theoretical (PPP method) study of the UV absorption spectra of 2-azaanthracene and four of its methyl-substituted derivatives. We find that the p bands of these compounds consist of two different vibronic * bands. Our experimental and theoretical results suggest a rule for evaluating the effect of methyl groups on * transition energies as a function of the charge on the atoms. We interpret the reasons for the different effects of a polar solvent and hydrogen bonding on the * bands of these compounds.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 7–15, June, 1977.  相似文献   

10.
Conclusion The joint efforts of the laboratories with intermediate energies accelerators at ANL, KEK, LANL, LNPI, Saclay, SIN and TRIUMF produced a rather definite picture of the +pp reaction in the isobar region. However the problem of anomalies for the square-root branch point due to the production of isobar in the intermediate state have not been resolved so far. The poles obtained in different phenomenological analyses could be just the effective parametrization of these cuts (see e.g. [13]). Anyway, some singularities are definitely necessary to describe the data.The experimental data in regions s < 2·05 GeV and s < 2·25 GeV are clearly insufficient. Further accumulation of the data in these regions is necessary. Polarized deuteron data are badly needed in the whole kinematical range [13]. Besides as it was mentioned before it is necessary to measure accurately cross sections of other inelastic reactions which are important for the investigation (observation?) of dibaryonsNN N, NN andd N, NN [21]. It would be of interest also to measure cross sections of non quasi two-particle channels likeNN N, 2N andd N, 2N [22]. (In the case ofNN scattering quasi two-particle channels are known to dominate in a wide energy range.)Presented at the symposium Mesons and Light Nuclei, Bechyn, Czechoslovakia, May 27–June 1, 1985.I am grateful to L. A. Kondratyuk, M. G. Ryskin and M. I. Strikman for valuable discussions of the considered problems.  相似文献   

11.
The scattering cross section of the reaction + N N + , + N N + is calculated by the semiclassical method. It is predicted that the latter reaction occurs through N** resonance. The mass of this resonance, the spin, and isospin are found. The zero approximation with respect to the coupling constant between the - and -mesons is considered.  相似文献   

12.
A realistic pion form factor model respecting the usual fundamental principles supplemented by reasonable assumptions is constructed by means of conformai mapping having some specific uniformization properties. The model includes the contributions of higher rho-resonances without any conflict with analyticity, provides a certain flexibility for the asymptotic behaviour and depends just on the physical parameters. The best fit of all existing data is achieved with(770),'(1600) and the asymptoticst –3/2. The predicted values of the pion charge radius, P-wave isovector scattering length, as well as theI=J = 1 scattering amplitude at the experimental measurable region coincide with the world averaged data.Dedicated to the 30th anniversary of the Joint Institute of Nuclear Research.The authors are indebted to Prof. V. A. Meshcheryakov, Dr. S. B. Gerasimov and Dr. D. Krupa for many stimulating and illuminating discussions.  相似文献   

13.
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   

14.
The development in time of the transmission through57Fe of a broad Lorenztian radiation is calculated numerically. Examples are given for=0 and/2, for the magnetic hyperfine case, and for=/2 for pure quadrupole splitting.  相似文献   

15.
The calculation of the secondary nucleons polarization in thepppp0 andppnp+ reactions at 1000 MeV is effected in the framework of the one-pion exchange model. It is shown that polarization is due to the interference of the resonant amplitude with the non-resonant amplitudes of theN virtual scattering. The angular dependence of the polarization is sensitive to the behaivour of theN scattering amplitudes off the mass shell.Submitted to the symposium Mesons and Light Nuclei, Liblice, Czechoslovakia, June 1981.  相似文献   

16.
From a finite size analysis we extract the structure factorS(p, N=) of the one dimensional AFH-model in the groundstate: The gross structure is well described byL (p) = –ln(1– p ). The fine structure which only contributes a few percent reveals a pronounced non-linear behavior inL(p) with a maximum atp=0.20 and a minimum atp=0.82.  相似文献   

17.
Using the semiempirical method of partial neglect of differential overlap (PNDO), we have calculated the wave functions, energies, orbital configurations of electronic states, oscillator strengths of transitions, electronic density distributions, and dipole moments for the molecule of biologically active 8–azagona–12,17–dione, containing a conformationally rigid –acyl––aminovinylcarbonyl fragment. It has been established that as to their orbital nature the excited lower and higher singlet electronic states of this molecule are of the n*– and * type respectively. The results of the theoretical analysis are in good qualitative agreement with the spectral data on absorption and luminescence. The calculations of the intermolecular interaction of the compound under consideration with a medium show that the molecular systems under consideration can possess a dynamic multicenter structure.  相似文献   

18.
Summary The paper presents the results of a theoretical analysis of an optical traveling-wave amplifier, to whose input are applied monochromatic pulses of frequency equal to the transition frequency. At distances zp(c/2) |2N2–N1|/ /(N1–N2) where p>1, and for <20aN1 all input pulses assume the form of a stationary pulse (see Eq. (33)). The stationary signal intensity, duration and total energy are substantially dependent on the nonresonant loss in the medium, the relaxation time T2 and the initial inversion population difference N1. For loss values >20aN1 the input pulses are attenuated.In the amplifier model considered we have assumed the laser medium to have a uniformly broadened line. This enables us to apply the results of the investigation to a ruby laser which satisfies this condition (by excluding low temperatures).The neglect of pumping and the lifetime T1 is permissible for values of not too close to 20aN1.Izvestiya VUZ. Radiofizika, Vol. 8, No. 5, pp. 899–908, 1965  相似文献   

19.
The differential and total cross sections of the processes and 3 are calculated on the basis of the vector-dominance model and current algebra. Up to a photon energy of order 1 GeV, the cross sections of these processes are very small, and it is only in the region of the resonance that values 0.01–0.05 mb are reached.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 84–88, September, 1980.I am very grateful to Professor M. P. Rekalo for constant interest in the work.  相似文献   

20.
The optical constants of single crystals of hexagonal selenium in the region of the intrinsic absorption edge in polarized light were investigated. The absorption edge for light polarized normal to the optical axis of the crystal is displaced towards longer wavelengths. The absorption maximum of hexagonal selenium for a wavelength of 0·6 is interpreted as the maximum corresponding to interaction between neighbouring chains and in connection with this the position of the absorption edge of different modifications of selenium is discussed.
. , , . 0,6 , .


In conclusion the author wishes to thank Dr. E. Klier and R. Kuel for valuable discussions and advice. He thanks laboratory assistants J. Ontl and O. Kundrátová for help in the work.  相似文献   

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