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1.
On the basis of an arbitrary (V, A) structure of the neutral weak ¯ee and LL currents (L=, M0) a study is made of the processes of production in colliding electron-positron beams of pairs of heavy leptons with subsequent decays in accordance with the schemes e+evµv) + +( anything) and e+eM0e+ve) + M0( anything). The energy spectrum and asymmetry of the distribution of the produced muons are investigated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 66–70, February, 1981.  相似文献   

2.
The long-wave * transitions and weak n * transitions are discussed for several compounds of practical importance. Wave functions are presented for aliphatic ketones, acids, and esters.  相似文献   

3.
The paper considers the formation of gluon and quark jets in the inelastic scattering of electrons by nucleons with large momentum transfers. It is assumed that these jets are created by the processes e+qe+q+g and e+ g e+q+q, where q is a quark and g is a gluon. The angular distributions of gluon and quark jets are calculated in the lowest order in the quark-gluon coupling constant. It is shown that after integration the processes e+qe+q+g and e+g e+q+¯q lead to violation of the scaling invariance of deep-inelastic scattering of electrons by nucleons.Translated from Izvestiya Vysshkikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 68–73, September, 1981.  相似文献   

4.
T-odd correlations that are possible in the processes n + p d + and n + p d + e+ + ee- and that arise due to the capture of thermal neutrons are determined in terms of threshold amplitudes (for the process n + p d + @#@) or electromagnetic inelastic form factors (for the process n + p d+ e+ + ee§-). The mechanism of these reactions is not given in concrete form, but those general properties of the electromagnetic hadronic current are used that are preserved with three-dimensional reflections.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 8–13, October, 1986.  相似文献   

5.
By establishing the correspondence between the substitution rule (aa nb; ba) and the transformation on the value of =tan by1/(n+) in the cut-and-project (CP) method, it is proved that the necessary and sufficient conditions for a binary quasiperiodic (QP) sequence made by the CP method to be self-similar is that is a quadratic irrational (QI) number. And, vice versa, the necessary condition for a binary self-similar sequence generated by the substitution rule to be obtainable by the CP method is that the corresponding substitution rule can be rewritten as a simple composition of transformations with the type (aa nb; ba). To illustrate some physical properties of the self-similar QP chains associated with QI numbers, we analyze the scaling behaviour of the wave function atE=0 for an off-diagnonal tight-binding model. It is shown that the wave function atE=0 grows at most by a power-law for the QP lattices, characterized by a special class of QI numbers. For the QP chains associated with general QI numbers, with the same logic, the typical scaling behaviour of the wave function is conjectured to be the same.  相似文献   

6.
A symmetry in the quantum logic (L, M) is defined as a pair of bijections :L L andv :M M such that the probabilities are preserved. Some properties of the symmetries are investigated.  相似文献   

7.
In this work we used x-ray structural analysis to investigate the martensitic transformations (MTs)B2R andRB19 in Ti(Ni, Fe) alloys containing 1, 2.5, 4, 5 at. % Fe, and the effect of heat treatment on the MT temperatures and sequence. In the majority of cases, it was found that the MTB2R proceeds through a two-phase region (+R). Heat treatment leads to a narrowing of the temperature interval of the existence of the two-phase region, weakly affects the onset temperatures of the MTsB2R TR andRB19 Ms, and sharply increases the temperature-of the end of the MT Me. The existence of the two-phase region is related to the two MT channelsB2R andB2B19 initially intrinsic to the allovs of the given compositions.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 19–22, December, 1989.  相似文献   

8.
We report exact results for one-dimensional reaction-diffusion modelsA+Ainert,A+AA, andA+Binert, where in the latter case like particles coagulate on encounters and move as clusters. Our study emphasizes anisotropy of hopping rates; no changes in universal properties are found, due to anisotropy, in all three reactions. The method of solution employs mapping onto a model of coagulating positive integer charges. The dynamical rules are synchronous, cellular-automaton type. All the asymptotic large-time results for particle densities are consistent, in the framework of universality, with other model results with different dynamical rules, when available in the literature.  相似文献   

9.
Matysina  Z. A.  Shchur  D. V. 《Russian Physics Journal》2001,44(11):1237-1243
Structural phase transformations of the hcp bcc fct fcc fct ( ) type in titanium hydrides TiH x experimentally found to occur with increase in the hydrogen concentration x are studied theoretically. Free energy phases are statistically calculated, and their concentration dependence is determined. Phase transformation temperatures are found from intersection points of free energy curves and from points of common tangents to the curves. The energy parameters of the system are estimated. The calculation results are compared with the experimental data.  相似文献   

10.
Low's theorem [1] on the emission of soft -rays is applied to a study of p + p p+p+ and + p 0+ n + reactions. The first two terms in the expansion of the differential cross sections for these processes in powers of the photon energy are obtained (for proton scattering in the ultrarelativistic limit).In conclusion, we wish to express our gratitude to S. M. Bilen'kii and R. M. Ryndin for directing this work.  相似文献   

11.
Within the Nuclear Nambu-Jona-Lasinio model of light nuclei (the NNJL model), describing strong low-energy nuclear interactions, we compute the width of the energy level of the ground state of pionic deuterium. The theoretical value fits well the experimental data. Using the cross-sections for the reactions e + d p + p + e- and e + d p + n + e, computed in the NNJL model, and the experimental values of the events of these reactions, detected by the SNO Collaboration, we compute the boron neutrino fluxes. The theoretical values agree well with the experimental data and the theoretical predictions within the Standard Solar Model by Bahcall. We argue the applicability of the constraints on the astrophysical factor for the solar proton burning, imposed by helioseismology, to the width of the energy level of the ground state of pionic deuterium. We show that the experimental data on the width satisfy these constraints. This testifies an indirect measurement of the recommended value of the astrophysical factor for the solar proton burning in terrestrial laboratories in terms of the width of the energy level of the ground state of pionic deuterium.  相似文献   

12.
We study theE-dependence of the Lyapounov exponent <(E)> of an electron with energyE in the one dimensional Anderson model with off diagonal disorder. In the neighbourhood of the band centre we find for nonzero disorder E)>log–1 E0 forE0, but all even moments of Re(E) diverge logarithmically. As the probability of Re (E)=0 decreases to zero forE0 we conclude that the electron is always exponentially localised.  相似文献   

13.
Quantum chromodynamics methods are used to calculate the section of the reaction a0 0 with formation as an intermediate state of the meson a0(980), which is interpreted as a bound state of two quark-antiquark pairs, formed upon dissociation of two virtual photons, with which an electron and positron are exchanged in incident e- and e+-beams. It is shown that the a0 20 decay is significantly more suppressed than the a0 0 decay.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 19–23, July, 1991.  相似文献   

14.
Nucleon polarizations are examined in the hypernucleus decays5He, 4He + p + ,4H, 3H + p + , and4H, 3He + n + . The effect of the strong interaction in the final state is taken into account. A significant role is predicted for the resonance interaction in the p-4He system in the formation of the proton polarization in the5He decay. It is also shown that in the4H, 3H + p + decay the proton-polarization components should attain significant magnitudes, while in the charge-exchange decay4H, 3He + n + , the neutron polarization is expected to be not too large.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 100–103, October, 1988.  相似文献   

15.
An analysis of the radiative decay1P1 1S0 + of charmonium is performed by using the sum rules of quantum chromodynamics (QCD). A sum rule that allows for luon power corrections is obtained, and the decay width c + is computed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 80–84, November, 1991.Finally, the author express thanks to professor R. N. Faustov for valuable advice and useful discussion of the resulting work.  相似文献   

16.
The ring (Frobenius algebra) of local observables for topological -models on 1 with values in the grassmannianG(s, n) is known to be the same as the quotient of the homology ring of the target space by the (inhomogeneous) ideal generated by the so-called quantum correction. While the need for a quantum correction comes from algebraic motivations in field theory, the aim of this paper is to understand its geometric meaning. The simple examples of 1 n models tell us that the quantum correction comes by restriction on the boundary of the moduli spaces which allows to compute intersections on moduli spaces of lower degrees. We will check this point of view for the case of 1 G(s,n) models, yielding a proof of the algebraic result from physics in terms of the geometry of the -model itself.Work partially supported by National Project 40% Probabilistic and geometrical methods in Mathematical Physics and by CNR-Gruppo Nazionale di Fisica Matematica.  相似文献   

17.
We investigate the statistics of the numberN(R, S) of lattice pointsnZ 2, in an annular domain (R, w)=(R+w)A\RA, whereR, w>0. HereA is a fixed convex set with smooth boundary andw is chosen so that the area of (R, w) isS. The statistics comes fromR being taken as random (with a smooth density) in some interval [c 1 T,c 2,T],c 2>c 1>0. We find that in the limitT the variance and distribution of N=N(R; S)–S depend strongly on howS grows withT. There is a saturation regimeS/T, asT, in which the fluctuations in N coming from the two boundaries of are independent. Then there is a scaling regime,S/Tz, 0<z<, in which the distribution depends onz in an almost periodic way going to a Gaussian asz0. The variance in this limit approachesz for genericA, but can be larger for degenerate cases. The former behavior is what one would expect from the Poisson limit of a distribution for annuli of finite area.  相似文献   

18.
We consider a stochastic system of particles in a two dimensional lattice and prove that, under a suitable limit (i.e.N, 0,N2const, whereN is the number of particles and is the mesh of the lattice) the one-particle distribution function converges to a solution of the two-dimensional Broadwell equation for all times for which the solution (of this equation) exists. Propagation of chaos is also proven.Research partially supported by CNR-PS-MMAIT  相似文献   

19.
An experimental investigation of one-dimensional, diffusion-limited A+BC chemical reactions is reported. The persistence of reactant segregation and the formation of a depletion zone is observed and expressed in terms of the universal time exponents: (motion of the boundary zone), (width of instantaneous product formation zone), (rate of instantaneous local formation of product), (rate of instantaneous global formation of product), etc. There is good agreement with the recently predicted and/or simulated values:=1/2,=1/6,=2/3,=1/2, in contrast to classical predictions (=0,=1/2,=0,=–1/2). Furthermore, classically the segregation would not be preserved and there would be no formation of a depletion zone and no motion (just dissipation) of the reaction zone. We also discuss the relations to electrode oxidation-reduction reactions, i.e., A+CC where C is a catalyst, electrode, or trap.  相似文献   

20.
It is remarked that the inference rule ( ) is superfluous for the sequential system GMQL introduced by H. Nishimura for the minimal quantum logic.  相似文献   

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