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1.
The deep inelastic structure function D(ω, q2) is calculated in the leading log approximation for . For larger ω up to ( the influence of reggeon cuts proves to slow down the growth of the structure function. A reggeon diagram technique is developed, and D is calculated up to a pre-exponent O(1), leading to D(ω, q2) ∝ q2 for . By assuming the reggeon diagrams when ω is still greater, one can expect to obtain a strong coupling behaviour: D(ω, q2) ∝ q2(ln ω)η (η <2). 相似文献
2.
During the last few years many dynamical systems have been identified, that are completely integrable or even such to allow an explicit solution of the equations of motion. Some of these systems have the form of classical one-dimensional many-body problems with pair interactions; others are more general. All of them are related to Lie algebras, and in all known cases the property of integrability results from the presence of higher (hidden) symmetries. This review presents from a general and universal viewpoint the results obtained in this field during the last few years. Besides it contains some new results both of physical and mathematical interest.The main focus is on the one-dimensional models of n particles interacting pairwise via potentials V(q) = g2ν(q) of the following 5 types: . Here (q) is the Weierstrass function, so that the first 3 cases are merely subcases of the fourth. The system characterized by the Toda nearest-neighbor potential, gj2exp[-a(qj?qj+1)], is moreover considered. Various generalizations of these models, naturally suggested by their association with Lie algebras, are also treated. 相似文献
3.
John Lekner 《Physica A》1982,112(3):544-556
We derive comparison identities for waves satisfying the equation d2Ψ/dz2+q2(z)Ψ=0. One of these identities is used to show that to second order in the product (wavenumber component normal to interface) × (interface thickness), the reflection amplitude is given by , where l is a legnth determined by the deviation of the interface profile from a step, and q1, q2 are the normal components of the wave numbers in media 1 and 2 on either side of the interface. For the continuous interfaces discussed, l is about two-fifths of the 10–90 interface thickness. The corresponding formula for the transmission amplitude is . 相似文献
4.
The charge density wave transition in 2H-TaS2near 75 K has been observed to be incommensurate, using electron diffraction, with along the 〈10.0〉 directions which, within the experimental uncertainty, remains temperature independent to about 14 K. Incommensurate charge density formation is also observed in AgxTaS2 samples for with an increase in q1 to when x?0.26. Within the experimental error q1 appears to be temperature independent to 25 K. 相似文献
5.
Yu. Oročko 《Reports on Mathematical Physics》1979,15(2):163-172
Let ,m? 1.Consider the operatorT0 = ?Δ+q with domain consisting of all bounded measurable functions , having bounded support, for which the distribution ?Δu+qu belongs to . The main result of the paper is essential self-adjointness of . The proof is independent of a method due to Kato who recently established the self-adjointness of a maximal Schrödinger operator corresponding to such potential. 相似文献
6.
H. Kleinert 《Physics letters. [Part B]》1976,62(1):77-80
In quark gluon theory with very small bare masses, -ψ, spontaneous breakdown of chiral symmetry generates sizable masses Mu, Md, Ms, … We find (. Scalar densities have well determined non-zero vaccum expectations at an SU(3) breaking of the vacuum c′ ≡ 〈0|u8|〉/〈0|uo|0〉 ≈ ? 16% 相似文献
7.
Yu.B. Bushnin A.F. Dunaitsev R.I. Dzelyadin S.V. Golovkin V.F. Konstantinov V.P. Kubarovsky L.G. Landsberg V.M. Leontiev G.P. Makarov V.A. Mukhin V.G. Rybakov T.I. Petrunina Yu.N. Simonov V.V. Smirnov A.M. Zaitsev A. Zallo 《Physics letters. [Part B]》1976,64(1):102-106
The difference of the cross sections for deep inelastic scattering of muons with average momenta 21 GeV/c with right and left helicity at large angles, i.e., with large momentum transfer, has been measured. No statistically-significant dependence of cross sections on the longitudinal polarization of muons has been found, i.e. no parity-nonconservation effects in deep inelastic μN interaction have been observed. The magnitude of the cross-section asymmetry may be represented as R = β〈Q2〉 = (? 4 ± 6) × 10?3 〈Q2, (GeV/c)2〉. The limitations Go(μ) = (+ 6 ± 10)G have been obtained for the constant Go(μ) of vector-axial interaction (hadron, V-A). 相似文献
8.
V.I. Inozemtsev 《Physics letters. A》1983,96(9):447-448
It is shown that a classical system with hamiltonian possesses a constant of the motion ; the quantum system with the same hamiltonian has no constants of the motion which are polynomials in the momenta of order not higher than three, except H. 相似文献
9.
10.
H. Braun M. Cornelssen H.-U. Martyn O. Erriquez S. Natali F. Romano D. Bertrand M. Csejthey-Barth J. Lemonne P. Renton P. Vilain D.C. Cundy T.I. Pedersen D. Waldren 《Physics letters. [Part B]》1973,47(2):185-188
The q2 variation of the factor 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 with λ+=0.027±0.008. 相似文献
11.
The values of at q2=0 for the neutron and the proton provide a measure of the average transverse separations squared, 〈〉, between a u or d quark and the rest of the partons in a nucleon. Using the measured values of the form factors (together with parton x-distributions), we find that 〈 for u quarks and 16.4 GeV?2 for d quarks in a proton. We speculate that the small difference between u and d quarks is caused by “quark pairing” and discuss other possible experimental signatures of quark pairing. 相似文献
12.
D.S. Narayan 《Nuclear Physics B》1973,59(1):299-304
Assuming Feynman's scaling law, Koba, Nielson and Olesen had shown that as s → ∞, (i) 〈nq〉/〈n〉q → dq where dq is independent of s and . The derivation of the latter result is, however, not rigorous and it does not follow, as a necessary consequence, from the scaling law. 相似文献
13.
D.J. Gates 《Physica A》1975,81(1):47-71
The k-particle, infinite-volume distribution functions and modified Ursell correlation functions of a classical system of particles with the two-body potential are considered. The limiting values of the functions and in the limit γ → 0 are calculated, under fairly weak conditions on q and K, by a method involving functional differentiation. These limiting functions are used to describe the molecular structure of the various states of the system both in the range of the potential q(r) and in the rage of the potential γνK(γr). The direct correlation function c? (r, γ) is also considered and it is shown that for , , for all one-phase states, where β is the reciprocal temperature. Special cases of our results confirm those of other authors, including the well-known results of Ornstein and Zernike. 相似文献
14.
The use of a scaling variable with α being constant provides an extension of the KNO scaling to low energies. A generalized Wroblewski-formula to higher moments is obtained. We tentatively connect α with the leading particle effect. 相似文献
15.
The one-electron momentum distribution function for an electron gas is investigated by a diagrammatic analysis of perturbation theory. It is shown that has the following exact asymptotic form for large k (k ? pF; pF, the Fermi momentum): , where g?(0) is the zero-distance value of the spin-up-spin-down pair correlation function. The physical implications of the above asymptotic form are discussed. 相似文献
16.
The temperature dependence of the field emission flicker noise spectral density functions has been investigated for potassium adsorbed on tungsten (112) planes by a probe hole technique. By integration of the spectral density functions the noise power for different frequency intervals Δ? is obtained. From the exponential temperature dependence of noise power “activation energies” qΔ? are determined. Plots of these energies versus coverage show a similar “oscillating” behaviour as recently found for or which indicates phase transitions of the adsorbed potassium submonolayers. The noise activation energies are discussed in terms of existing models and a comparison is made between the experimental q values and surface diffusion energies Ed as determined by conventional methods. 相似文献
17.
We calculate helicity amplitudes and decay rates for Zweig-forbidden radiative decays of a bound state into states in lowest-order QCD. We employ a new technique of scalarizing loop integrals by using covariant helicity projectors. Thereby we are able to integrate analytically all occuring loop integrals.When applied to decays our results are in reasonable agreement with present experimental results. ψ′ decays will provide a further test of the model. Transitions from bottonium to charmonium are most interesting since there all dynamical assumptions are well satisfied. Unfortunately the transitions rates are very small. 相似文献
18.
Hyperfine structure of the (0, 0, 1) - (1, 0, 1) transition of methanol has been investigated by beam absorption and of the (J, 1, 3?) → (J, 1, 3+) transitions for J = 2, 3, and 6 by beam-maser spectroscopy. The best-fit results for the spin-rotation and spin-spin coupling constants and , respectively, are in kHz1: , , , , , and (. 相似文献
19.
20.
Starting from the Fubini-Dashen-Gell-Mann sum rule, we relate the slope of the pion electromagnetic form factor at t = 0 to the rotational properties of the photopion production amplitudes. When the pion's charge radius is calculated with a simple short range correlation model for the production amplitudes (diffractive processes being forbidden), the result is . 相似文献