We prove that the correction to exponential decay of the truncated two points
function in the homogeneous positive field Ising model is c∥x∥−(d−1)/2.
The proof is based on the development in the random current representation of a
"modern" Ornstein-Zernike theory, as developed by Campanino, Ioffe and Velenik.Comment: 26 pages, 7 figures, details adde