1. We use the notation of S.W. Lovesey, Theory of Neutron Scattering from Condensed Matter, Clarendon Press., Oxford (1984).
2. Neutron scattering data reported in this paper mostly show the quantity $$ \tilde{I}\left( {\vec{Q},\omega } \right) = \left( {1/2} \right)\sum\nolimits_{{\alpha \beta }} {\left( {{\delta_{{\alpha \beta }}} - {{\hat{Q}}_{\alpha }}{{\hat{Q}}_{\beta }}} \right)} {S^{{\alpha \beta }}}\left( {\vec{Q},\omega } \right) $$ which is proportional to the scattering cross section of Eq. (7)
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