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arXiv:hep-th/9407062

The Dynamical Correlation Function of the XXZ Model

Robert Weston, A. Hamid Bougourzi

Published Jul 13, 1994• 2 citations
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Abstract

We perform a spectral decomposition of the dynamical correlation function of the spin $1/2$ XXZ model into an infinite sum of products of form factors. Beneath the four-particle threshold in momentum space the only non-zero contributions to this sum are the two-particle term and the trivial vacuum term. We calculate the two-particle term by making use of the integral expressions for form factors provided recently by the Kyoto school. We evaluate the necessary integrals by expanding to twelfth order in $q$. We show plots of $S(w,k)$, for $k=0$ and $π$ at various values of the anisotropy parameter, and for fixed anisotropy at various $k$ around $0$ and $π$.

DOI
10.48550/arxiv.hep-th/9407062

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