Dynamic structure factor for a ferromagnet in the scaling region to first order inε=6d

Abstract
The dynamic structure factor for a model ferromagnet is calculated to order ε=6d for TTc. The dynamic shape function is extracted from the structure factor and plotted for various values of ε and x=kξ, where ξ is the correlation length and k the wave number. In the vicinity of Tc and for ε0.95 peaks appear which are characteristic of sloppy spin-wave modes.