Inelastic neutron scattering studies of the paramagnetic phase in iron

The paramegnetic phase of Fe(4%-Si) has been investigated by using polarized neutron scattering for temperatures ranging from the Curie temperature to ~1.2Tc and for q's ranging from 0.12 to 0.5 ^-1 at the 011 reciprocal lattice point. All measurements were put on an absolute intensity scale via simultaneously measured phonon cross sections. Our energy resolved measurements S(→Q,ω) consisted of a broad energy distribution centered at zero energy transfer. However, no spin-wave-like peak was present in any of these constant-Q scans which contradicts the large "spin-wave" peak reported at $q=0.47$ ^-1 by Lynn. All recent theoretical models based upon this constant-Q peak should be reexamined.