Properties Of Form Factors Research Articles

ANNIHILATION POLES FOR FORM FACTORS IN THE XXZ MODEL

The annihilation poles for the form factors in the XXZ model are studied using vertex operators introduced in Ref. 1. An annihilation pole is the property of form factors according to which the residue of the 2n-particle form factor in such a pole can be expressed through linear combination of the (2n−2)-particle form factors. To prove this property we use the bosonization of the vertex operators in the XXZ model which was invented in Ref. 2.

Extraction of nuclear coupling constants from data on nuclear charge form factors

A possibility of extracting nuclear coupling constants from data on nuclear charge form factors is discussed. The method exploits analytic properties of form factors in the momentum transfer plane. As an illustration the form factor of4He is considered in detail. In this case the value\(g_{4_{He^3 He(^3 H)} }^2 /4\pi = 16 \pm 1\) has been obtained in excellent agreement with earlier determinations by means of other methods. Similar analysis of the16O form factor yields the first estimate of the oxygen-nucleon coupling∶\(g_{16_{O^{15} O(^{15} N)N} }^2 /4\pi = 64\).

Properties of Form Factors in Non-Local Theories

Properties of Form Factors in Non-Local Theories

Some remarks on the properties of form factors

We study the properties of a class of form factors, vanishing ast→−∞, and fulfilling in the cut plane |F(t)⩽Me exp[e|t|1/2](1+Δt)−m) for every e>0, where Δt is the distance to the cut. A form factorF in this class is uniquely determined by the discontinuity over the cut, 2i ImF, which exists as a distribution of finite order.F can be expressed in terms of ImF through a generalized unsubtracted dispersion relation. Sum rules and their implications for the asymptotic behaviour of ImF are discussed.

On a Non-local Electromagnetic Model for Electron and Muon Masses

In a phenomenological way, a non-local electromagnetic interaction with a Pauli term is assumed in order to explain the whole masses of electron and muon. Qualitative discussions are devoted to the properties of form factors on the assumption of similar internal structures for both particles. (auth)

Properties of form factors in non-local theories

The conditions for absence of non-causal actions over large time intervals in non-local theories are expressed as conditions on the Fourier transform of the form function.