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arXiv · hep-th/9407089

Direct Calculation of the Boundary $S$ Matrix for the Open Heisenberg Chain

M. T. Grisaru·Luca Mezincescu·Rafael I. Nepomechie
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Abstract

We calculate the boundary $S$ matrix for the open antiferromagnetic spin $1/2$ isotropic Heisenberg chain with boundary magnetic fields. Our approach, which starts from the model's Bethe Ansatz solution, is an extension of the Korepin-Andrei-Destri method. Our result agrees with the boundary $S$ matrix for the boundary sine-Gordon model with $β^2 \rightarrow 8π$ and with ``fixed'' boundary conditions.

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M. T. Grisaru, Luca Mezincescu, Rafael I. Nepomechie. 1994-07-15. Direct Calculation of the Boundary $S$ Matrix for the Open Heisenberg Chain. https://doi.org/10.1088/0305-4470%2F28%2F4%2F025

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