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arXiv · hep-th/9407062

The Dynamical Correlation Function of the XXZ Model

Robert A. Weston·A. H. Bougourzi
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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 $π$.

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Robert A. Weston, A. H. Bougourzi. 1994-07-13. The Dynamical Correlation Function of the XXZ Model. https://arxiv.org/abs/hep-th/9407062

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